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Create symlinks to all /home/folder1/*.txt files with the same name in current directory

find /home/folder1/*.txt -type f -exec ln -s {} \;

['find', 'ln']

Output a Bash command to accomplish the following task. Task: Create symlinks to all /home/folder1/*.txt files with the same name in current directory Bash Command:<START>find /home/folder1/*.txt -type f -exec ln -s {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # ln\n\n> Creates links to files and directories.\n> More information: <https://www.gnu.org/software/coreutils/ln>.\n\n- Create a symbolic link to a file or directory:\n\n`ln -s {{/path/to/file_or_directory}} {{path/to/symlink}}`\n\n- Overwrite an existing symbolic link to point to a different file:\n\n`ln -sf {{/path/to/new_file}} {{path/to/symlink}}`\n\n- Create a hard link to a file:\n\n`ln {{/path/to/file}} {{path/to/hardlink}}`\n Task: Create symlinks to all /home/folder1/*.txt files with the same name in current directory Bash Command:<START>find /home/folder1/*.txt -type f -exec ln -s {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. ln(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training ln(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON LN(1) User Commands LN(1) NAME top ln - make links between files SYNOPSIS top ln [OPTION]... [-T] TARGET LINK_NAME ln [OPTION]... TARGET ln [OPTION]... TARGET... DIRECTORY ln [OPTION]... -t DIRECTORY TARGET... DESCRIPTION top In the 1st form, create a link to TARGET with the name LINK_NAME. In the 2nd form, create a link to TARGET in the current directory. In the 3rd and 4th forms, create links to each TARGET in DIRECTORY. Create hard links by default, symbolic links with --symbolic. By default, each destination (name of new link) should not already exist. When creating hard links, each TARGET must exist. Symbolic links can hold arbitrary text; if later resolved, a relative link is interpreted in relation to its parent directory. Mandatory arguments to long options are mandatory for short options too. --backup[=CONTROL] make a backup of each existing destination file -b like --backup but does not accept an argument -d, -F, --directory allow the superuser to attempt to hard link directories (note: will probably fail due to system restrictions, even for the superuser) -f, --force remove existing destination files -i, --interactive prompt whether to remove destinations -L, --logical dereference TARGETs that are symbolic links -n, --no-dereference treat LINK_NAME as a normal file if it is a symbolic link to a directory -P, --physical make hard links directly to symbolic links -r, --relative with -s, create links relative to link location -s, --symbolic make symbolic links instead of hard links -S, --suffix=SUFFIX override the usual backup suffix -t, --target-directory=DIRECTORY specify the DIRECTORY in which to create the links -T, --no-target-directory treat LINK_NAME as a normal file always -v, --verbose print name of each linked file --help display this help and exit --version output version information and exit The backup suffix is '~', unless set with --suffix or SIMPLE_BACKUP_SUFFIX. The version control method may be selected via the --backup option or through the VERSION_CONTROL environment variable. Here are the values: none, off never make backups (even if --backup is given) numbered, t make numbered backups existing, nil numbered if numbered backups exist, simple otherwise simple, never always make simple backups Using -s ignores -L and -P. Otherwise, the last option specified controls behavior when a TARGET is a symbolic link, defaulting to -P. AUTHOR top Written by Mike Parker and David MacKenzie. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top link(2), symlink(2) Full documentation <https://www.gnu.org/software/coreutils/ln> or available locally via: info '(coreutils) ln invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 LN(1) Pages that refer to this page: dh_link(1), pmlogmv(1), update-alternatives(1), link(2), symlink(2), hier(7), symlink(7), sln(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Create symlinks to all /home/folder1/*.txt files with the same name in current directory Bash Command:<START>find /home/folder1/*.txt -type f -exec ln -s {} \;<END>

Create symlinks to all /home/folder2/*.txt files with the same name in current directory

find /home/folder2/*.txt -type f -exec ln -s {} \;

['find', 'ln']

Output a Bash command to accomplish the following task. Task: Create symlinks to all /home/folder2/*.txt files with the same name in current directory Bash Command:<START>find /home/folder2/*.txt -type f -exec ln -s {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # ln\n\n> Creates links to files and directories.\n> More information: <https://www.gnu.org/software/coreutils/ln>.\n\n- Create a symbolic link to a file or directory:\n\n`ln -s {{/path/to/file_or_directory}} {{path/to/symlink}}`\n\n- Overwrite an existing symbolic link to point to a different file:\n\n`ln -sf {{/path/to/new_file}} {{path/to/symlink}}`\n\n- Create a hard link to a file:\n\n`ln {{/path/to/file}} {{path/to/hardlink}}`\n Task: Create symlinks to all /home/folder2/*.txt files with the same name in current directory Bash Command:<START>find /home/folder2/*.txt -type f -exec ln -s {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. ln(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training ln(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON LN(1) User Commands LN(1) NAME top ln - make links between files SYNOPSIS top ln [OPTION]... [-T] TARGET LINK_NAME ln [OPTION]... TARGET ln [OPTION]... TARGET... DIRECTORY ln [OPTION]... -t DIRECTORY TARGET... DESCRIPTION top In the 1st form, create a link to TARGET with the name LINK_NAME. In the 2nd form, create a link to TARGET in the current directory. In the 3rd and 4th forms, create links to each TARGET in DIRECTORY. Create hard links by default, symbolic links with --symbolic. By default, each destination (name of new link) should not already exist. When creating hard links, each TARGET must exist. Symbolic links can hold arbitrary text; if later resolved, a relative link is interpreted in relation to its parent directory. Mandatory arguments to long options are mandatory for short options too. --backup[=CONTROL] make a backup of each existing destination file -b like --backup but does not accept an argument -d, -F, --directory allow the superuser to attempt to hard link directories (note: will probably fail due to system restrictions, even for the superuser) -f, --force remove existing destination files -i, --interactive prompt whether to remove destinations -L, --logical dereference TARGETs that are symbolic links -n, --no-dereference treat LINK_NAME as a normal file if it is a symbolic link to a directory -P, --physical make hard links directly to symbolic links -r, --relative with -s, create links relative to link location -s, --symbolic make symbolic links instead of hard links -S, --suffix=SUFFIX override the usual backup suffix -t, --target-directory=DIRECTORY specify the DIRECTORY in which to create the links -T, --no-target-directory treat LINK_NAME as a normal file always -v, --verbose print name of each linked file --help display this help and exit --version output version information and exit The backup suffix is '~', unless set with --suffix or SIMPLE_BACKUP_SUFFIX. The version control method may be selected via the --backup option or through the VERSION_CONTROL environment variable. Here are the values: none, off never make backups (even if --backup is given) numbered, t make numbered backups existing, nil numbered if numbered backups exist, simple otherwise simple, never always make simple backups Using -s ignores -L and -P. Otherwise, the last option specified controls behavior when a TARGET is a symbolic link, defaulting to -P. AUTHOR top Written by Mike Parker and David MacKenzie. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top link(2), symlink(2) Full documentation <https://www.gnu.org/software/coreutils/ln> or available locally via: info '(coreutils) ln invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 LN(1) Pages that refer to this page: dh_link(1), pmlogmv(1), update-alternatives(1), link(2), symlink(2), hier(7), symlink(7), sln(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Create symlinks to all /home/folder2/*.txt files with the same name in current directory Bash Command:<START>find /home/folder2/*.txt -type f -exec ln -s {} \;<END>

Create tar archive "dirall.tar" and copy all files from directory tree /tmp/a1 to it

find /tmp/a1 -exec tar -rvf dirall.tar {} \;

['find', 'tar']

Output a Bash command to accomplish the following task. Task: Create tar archive "dirall.tar" and copy all files from directory tree /tmp/a1 to it Bash Command:<START>find /tmp/a1 -exec tar -rvf dirall.tar {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # tar\n\n> Archiving utility.\n> Often combined with a compression method, such as `gzip` or `bzip2`.\n> More information: <https://www.gnu.org/software/tar>.\n\n- [c]reate an archive and write it to a [f]ile:\n\n`tar cf {{path/to/target.tar}} {{path/to/file1 path/to/file2 ...}}`\n\n- [c]reate a g[z]ipped archive and write it to a [f]ile:\n\n`tar czf {{path/to/target.tar.gz}} {{path/to/file1 path/to/file2 ...}}`\n\n- [c]reate a g[z]ipped archive from a directory using relative paths:\n\n`tar czf {{path/to/target.tar.gz}} --directory={{path/to/directory}} .`\n\n- E[x]tract a (compressed) archive [f]ile into the current directory [v]erbosely:\n\n`tar xvf {{path/to/source.tar[.gz|.bz2|.xz]}}`\n\n- E[x]tract a (compressed) archive [f]ile into the target directory:\n\n`tar xf {{path/to/source.tar[.gz|.bz2|.xz]}} --directory={{path/to/directory}}`\n\n- [c]reate a compressed archive and write it to a [f]ile, using the file extension to [a]utomatically determine the compression program:\n\n`tar caf {{path/to/target.tar.xz}} {{path/to/file1 path/to/file2 ...}}`\n\n- Lis[t] the contents of a tar [f]ile [v]erbosely:\n\n`tar tvf {{path/to/source.tar}}`\n\n- E[x]tract files matching a pattern from an archive [f]ile:\n\n`tar xf {{path/to/source.tar}} --wildcards "{{*.html}}"`\n Task: Create tar archive "dirall.tar" and copy all files from directory tree /tmp/a1 to it Bash Command:<START>find /tmp/a1 -exec tar -rvf dirall.tar {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. tar(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training tar(1) Linux manual page NAME | SYNOPSIS | NOTE | DESCRIPTION | OPTIONS | RETURN VALUE | SEE ALSO | BUG REPORTS | COPYRIGHT | COLOPHON TAR(1) GNU TAR Manual TAR(1) NAME top tar - an archiving utility SYNOPSIS top Traditional usage tar {A|c|d|r|t|u|x}[GnSkUWOmpsMBiajJzZhPlRvwo] [ARG...] UNIX-style usage tar -A [OPTIONS] -f ARCHIVE ARCHIVE... tar -c [-f ARCHIVE] [OPTIONS] [FILE...] tar -d [-f ARCHIVE] [OPTIONS] [FILE...] tar -r [-f ARCHIVE] [OPTIONS] [FILE...] tar -t [-f ARCHIVE] [OPTIONS] [MEMBER...] tar -u [-f ARCHIVE] [OPTIONS] [FILE...] tar -x [-f ARCHIVE] [OPTIONS] [MEMBER...] GNU-style usage tar {--catenate|--concatenate} [OPTIONS] --file ARCHIVE ARCHIVE... tar --create [--file ARCHIVE] [OPTIONS] [FILE...] tar {--diff|--compare} [--file ARCHIVE] [OPTIONS] [FILE...] tar --delete [--file ARCHIVE] [OPTIONS] [MEMBER...] tar --append [--file ARCHIVE] [OPTIONS] [FILE...] tar --list [--file ARCHIVE] [OPTIONS] [MEMBER...] tar --test-label [--file ARCHIVE] [OPTIONS] [LABEL...] tar --update [--file ARCHIVE] [OPTIONS] [FILE...] tar {--extract|--get} [--file ARCHIVE] [OPTIONS] [MEMBER...] NOTE top This manpage is a short description of GNU tar. For a detailed discussion, including examples and usage recommendations, refer to the GNU Tar Manual available in texinfo format. If the info reader and the tar documentation are properly installed on your system, the command info tar should give you access to the complete manual. You can also view the manual using the info mode in emacs(1), or find it in various formats online at https://www.gnu.org/software/tar/manual If any discrepancies occur between this manpage and the GNU Tar Manual, the later shall be considered the authoritative source. DESCRIPTION top GNU tar is an archiving program designed to store multiple files in a single file (an archive), and to manipulate such archives. The archive can be either a regular file or a device (e.g. a tape drive, hence the name of the program, which stands for tape archiver), which can be located either on the local or on a remote machine. Option styles Options to GNU tar can be given in three different styles. In traditional style, the first argument is a cluster of option letters and all subsequent arguments supply arguments to those options that require them. The arguments are read in the same order as the option letters. Any command line words that remain after all options have been processed are treated as non-option arguments: file or archive member names. For example, the c option requires creating the archive, the v option requests the verbose operation, and the f option takes an argument that sets the name of the archive to operate upon. The following command, written in the traditional style, instructs tar to store all files from the directory /etc into the archive file etc.tar, verbosely listing the files being archived: tar cfv etc.tar /etc In UNIX or short-option style, each option letter is prefixed with a single dash, as in other command line utilities. If an option takes an argument, the argument follows it, either as a separate command line word, or immediately following the option. However, if the option takes an optional argument, the argument must follow the option letter without any intervening whitespace, as in -g/tmp/snar.db. Any number of options not taking arguments can be clustered together after a single dash, e.g. -vkp. An option that takes an argument (whether mandatory or optional) can appear at the end of such a cluster, e.g. -vkpf a.tar. The example command above written in the short-option style could look like: tar -cvf etc.tar /etc or tar -c -v -f etc.tar /etc In GNU or long-option style, each option begins with two dashes and has a meaningful name, consisting of lower-case letters and dashes. When used, the long option can be abbreviated to its initial letters, provided that this does not create ambiguity. Arguments to long options are supplied either as a separate command line word, immediately following the option, or separated from the option by an equals sign with no intervening whitespace. Optional arguments must always use the latter method. Here are several ways of writing the example command in this style: tar --create --file etc.tar --verbose /etc or (abbreviating some options): tar --cre --file=etc.tar --verb /etc The options in all three styles can be intermixed, although doing so with old options is not encouraged. Operation mode The options listed in the table below tell GNU tar what operation it is to perform. Exactly one of them must be given. The meaning of non-option arguments depends on the operation mode requested. -A, --catenate, --concatenate Append archives to the end of another archive. The arguments are treated as the names of archives to append. All archives must be of the same format as the archive they are appended to, otherwise the resulting archive might be unusable with non-GNU implementations of tar. Notice also that when more than one archive is given, the members from archives other than the first one will be accessible in the resulting archive only when using the -i (--ignore-zeros) option. Compressed archives cannot be concatenated. -c, --create Create a new archive. Arguments supply the names of the files to be archived. Directories are archived recursively, unless the --no-recursion option is given. -d, --diff, --compare Find differences between archive and file system. The arguments are optional and specify archive members to compare. If not given, the current working directory is assumed. --delete Delete from the archive. The arguments supply names of the archive members to be removed. At least one argument must be given. This option does not operate on compressed archives. There is no short option equivalent. -r, --append Append files to the end of an archive. Arguments have the same meaning as for -c (--create). -t, --list List the contents of an archive. Arguments are optional. When given, they specify the names of the members to list. --test-label Test the archive volume label and exit. When used without arguments, it prints the volume label (if any) and exits with status 0. When one or more command line arguments are given. tar compares the volume label with each argument. It exits with code 0 if a match is found, and with code 1 otherwise. No output is displayed, unless used together with the -v (--verbose) option. There is no short option equivalent for this option. -u, --update Append files which are newer than the corresponding copy in the archive. Arguments have the same meaning as with the -c and -r options. Notice, that newer files don't replace their old archive copies, but instead are appended to the end of archive. The resulting archive can thus contain several members of the same name, corresponding to various versions of the same file. -x, --extract, --get Extract files from an archive. Arguments are optional. When given, they specify names of the archive members to be extracted. --show-defaults Show built-in defaults for various tar options and exit. -?, --help Display a short option summary and exit. --usage Display a list of available options and exit. --version Print program version and copyright information and exit. OPTIONS top Operation modifiers --check-device Check device numbers when creating incremental archives (default). -g, --listed-incremental=FILE Handle new GNU-format incremental backups. FILE is the name of a snapshot file, where tar stores additional information which is used to decide which files changed since the previous incremental dump and, consequently, must be dumped again. If FILE does not exist when creating an archive, it will be created and all files will be added to the resulting archive (the level 0 dump). To create incremental archives of non-zero level N, you need a copy of the snapshot file created for level N-1, and use it as FILE. When listing or extracting, the actual content of FILE is not inspected, it is needed only due to syntactical requirements. It is therefore common practice to use /dev/null in its place. --hole-detection=METHOD Use METHOD to detect holes in sparse files. This option implies --sparse. Valid values for METHOD are seek and raw. Default is seek with fallback to raw when not applicable. -G, --incremental Handle old GNU-format incremental backups. --ignore-failed-read Do not exit with nonzero on unreadable files. --level=NUMBER Set dump level for a created listed-incremental archive. Currently only --level=0 is meaningful: it instructs tar to truncate the snapshot file before dumping, thereby forcing a level 0 dump. -n, --seek Assume the archive is seekable. Normally tar determines automatically whether the archive can be seeked or not. This option is intended for use in cases when such recognition fails. It takes effect only if the archive is open for reading (e.g. with --list or --extract options). --no-check-device Do not check device numbers when creating incremental archives. --no-seek Assume the archive is not seekable. --occurrence[=N] Process only the Nth occurrence of each file in the archive. This option is valid only when used with one of the following subcommands: --delete, --diff, --extract or --list and when a list of files is given either on the command line or via the -T option. The default N is 1. --restrict Disable the use of some potentially harmful options. --sparse-version=MAJOR[.MINOR] Set which version of the sparse format to use. This option implies --sparse. Valid argument values are 0.0, 0.1, and 1.0. For a detailed discussion of sparse formats, refer to the GNU Tar Manual, appendix D, "Sparse Formats". Using the info reader, it can be accessed running the following command: info tar 'Sparse Formats'. -S, --sparse Handle sparse files efficiently. Some files in the file system may have segments which were actually never written (quite often these are database files created by such systems as DBM). When given this option, tar attempts to determine if the file is sparse prior to archiving it, and if so, to reduce the resulting archive size by not dumping empty parts of the file. Overwrite control These options control tar actions when extracting a file over an existing copy on disk. -k, --keep-old-files Don't replace existing files when extracting. --keep-newer-files Don't replace existing files that are newer than their archive copies. --keep-directory-symlink Don't replace existing symlinks to directories when extracting. --no-overwrite-dir Preserve metadata of existing directories. --one-top-level[=DIR] Extract all files into DIR, or, if used without argument, into a subdirectory named by the base name of the archive (minus standard compression suffixes recognizable by --auto-compress). --overwrite Overwrite existing files when extracting. --overwrite-dir Overwrite metadata of existing directories when extracting (default). --recursive-unlink Recursively remove all files in the directory prior to extracting it. --remove-files Remove files from disk after adding them to the archive. --skip-old-files Don't replace existing files when extracting, silently skip over them. -U, --unlink-first Remove each file prior to extracting over it. -W, --verify Verify the archive after writing it. Output stream selection --ignore-command-error Ignore subprocess exit codes. --no-ignore-command-error Treat non-zero exit codes of children as error (default). -O, --to-stdout Extract files to standard output. --to-command=COMMAND Pipe extracted files to COMMAND. The argument is the pathname of an external program, optionally with command line arguments. The program will be invoked and the contents of the file being extracted supplied to it on its standard input. Additional data will be supplied via the following environment variables: TAR_FILETYPE Type of the file. It is a single letter with the following meaning: f Regular file d Directory l Symbolic link h Hard link b Block device c Character device Currently only regular files are supported. TAR_MODE File mode, an octal number. TAR_FILENAME The name of the file. TAR_REALNAME Name of the file as stored in the archive. TAR_UNAME Name of the file owner. TAR_GNAME Name of the file owner group. TAR_ATIME Time of last access. It is a decimal number, representing seconds since the Epoch. If the archive provides times with nanosecond precision, the nanoseconds are appended to the timestamp after a decimal point. TAR_MTIME Time of last modification. TAR_CTIME Time of last status change. TAR_SIZE Size of the file. TAR_UID UID of the file owner. TAR_GID GID of the file owner. Additionally, the following variables contain information about tar operation mode and the archive being processed: TAR_VERSION GNU tar version number. TAR_ARCHIVE The name of the archive tar is processing. TAR_BLOCKING_FACTOR Current blocking factor, i.e. number of 512-byte blocks in a record. TAR_VOLUME Ordinal number of the volume tar is processing (set if reading a multi-volume archive). TAR_FORMAT Format of the archive being processed. One of: gnu, oldgnu, posix, ustar, v7. TAR_SUBCOMMAND A short option (with a leading dash) describing the operation tar is executing. Handling of file attributes --atime-preserve[=METHOD] Preserve access times on dumped files, either by restoring the times after reading (METHOD=replace, this is the default) or by not setting the times in the first place (METHOD=system). --delay-directory-restore Delay setting modification times and permissions of extracted directories until the end of extraction. Use this option when extracting from an archive which has unusual member ordering. --group=NAME[:GID] Force NAME as group for added files. If GID is not supplied, NAME can be either a user name or numeric GID. In this case the missing part (GID or name) will be inferred from the current host's group database. When used with --group-map=FILE, affects only those files whose owner group is not listed in FILE. --group-map=FILE Read group translation map from FILE. Empty lines are ignored. Comments are introduced with # sign and extend to the end of line. Each non-empty line in FILE defines translation for a single group. It must consist of two fields, delimited by any amount of whitespace: OLDGRP NEWGRP[:NEWGID] OLDGRP is either a valid group name or a GID prefixed with +. Unless NEWGID is supplied, NEWGRP must also be either a valid group name or a +GID. Otherwise, both NEWGRP and NEWGID need not be listed in the system group database. As a result, each input file with owner group OLDGRP will be stored in archive with owner group NEWGRP and GID NEWGID. --mode=CHANGES Force symbolic mode CHANGES for added files. --mtime=DATE-OR-FILE Set mtime for added files. DATE-OR-FILE is either a date/time in almost arbitrary format, or the name of an existing file. In the latter case the mtime of that file will be used. -m, --touch Don't extract file modified time. --no-delay-directory-restore Cancel the effect of the prior --delay-directory-restore option. --no-same-owner Extract files as yourself (default for ordinary users). --no-same-permissions Apply the user's umask when extracting permissions from the archive (default for ordinary users). --numeric-owner Always use numbers for user/group names. --owner=NAME[:UID] Force NAME as owner for added files. If UID is not supplied, NAME can be either a user name or numeric UID. In this case the missing part (UID or name) will be inferred from the current host's user database. When used with --owner-map=FILE, affects only those files whose owner is not listed in FILE. --owner-map=FILE Read owner translation map from FILE. Empty lines are ignored. Comments are introduced with # sign and extend to the end of line. Each non-empty line in FILE defines translation for a single UID. It must consist of two fields, delimited by any amount of whitespace: OLDUSR NEWUSR[:NEWUID] OLDUSR is either a valid user name or a UID prefixed with +. Unless NEWUID is supplied, NEWUSR must also be either a valid user name or a +UID. Otherwise, both NEWUSR and NEWUID need not be listed in the system user database. As a result, each input file owned by OLDUSR will be stored in archive with owner name NEWUSR and UID NEWUID. -p, --preserve-permissions, --same-permissions Set permissions of extracted files to those recorded in the archive (default for superuser). --same-owner Try extracting files with the same ownership as exists in the archive (default for superuser). -s, --preserve-order, --same-order Tell tar that the list of file names to process is sorted in the same order as the files in the archive. --sort=ORDER When creating an archive, sort directory entries according to ORDER, which is one of none, name, or inode. The default is --sort=none, which stores archive members in the same order as returned by the operating system. Using --sort=name ensures the member ordering in the created archive is uniform and reproducible. Using --sort=inode reduces the number of disk seeks made when creating the archive and thus can considerably speed up archivation. This sorting order is supported only if the underlying system provides the necessary information. Extended file attributes --acls Enable POSIX ACLs support. --no-acls Disable POSIX ACLs support. --selinux Enable SELinux context support. --no-selinux Disable SELinux context support. --xattrs Enable extended attributes support. --no-xattrs Disable extended attributes support. --xattrs-exclude=PATTERN Specify the exclude pattern for xattr keys. PATTERN is a globbing pattern, e.g. --xattrs-exclude='user.*' to include only attributes from the user namespace. --xattrs-include=PATTERN Specify the include pattern for xattr keys. PATTERN is a globbing pattern. Device selection and switching -f, --file=ARCHIVE Use archive file or device ARCHIVE. If this option is not given, tar will first examine the environment variable `TAPE'. If it is set, its value will be used as the archive name. Otherwise, tar will assume the compiled-in default. The default value can be inspected either using the --show-defaults option, or at the end of the tar --help output. An archive name that has a colon in it specifies a file or device on a remote machine. The part before the colon is taken as the machine name or IP address, and the part after it as the file or device pathname, e.g.: --file=remotehost:/dev/sr0 An optional username can be prefixed to the hostname, placing a @ sign between them. By default, the remote host is accessed via the rsh(1) command. Nowadays it is common to use ssh(1) instead. You can do so by giving the following command line option: --rsh-command=/usr/bin/ssh The remote machine should have the rmt(8) command installed. If its pathname does not match tar's default, you can inform tar about the correct pathname using the --rmt-command option. --force-local Archive file is local even if it has a colon. -F, --info-script=COMMAND, --new-volume-script=COMMAND Run COMMAND at the end of each tape (implies -M). The command can include arguments. When started, it will inherit tar's environment plus the following variables: TAR_VERSION GNU tar version number. TAR_ARCHIVE The name of the archive tar is processing. TAR_BLOCKING_FACTOR Current blocking factor, i.e. number of 512-byte blocks in a record. TAR_VOLUME Ordinal number of the volume tar is processing (set if reading a multi-volume archive). TAR_FORMAT Format of the archive being processed. One of: gnu, oldgnu, posix, ustar, v7. TAR_SUBCOMMAND A short option (with a leading dash) describing the operation tar is executing. TAR_FD File descriptor which can be used to communicate the new volume name to tar. If the info script fails, tar exits; otherwise, it begins writing the next volume. -L, --tape-length=N Change tape after writing Nx1024 bytes. If N is followed by a size suffix (see the subsection Size suffixes below), the suffix specifies the multiplicative factor to be used instead of 1024. This option implies -M. -M, --multi-volume Create/list/extract multi-volume archive. --rmt-command=COMMAND Use COMMAND instead of rmt when accessing remote archives. See the description of the -f option, above. --rsh-command=COMMAND Use COMMAND instead of rsh when accessing remote archives. See the description of the -f option, above. --volno-file=FILE When this option is used in conjunction with --multi-volume, tar will keep track of which volume of a multi-volume archive it is working in FILE. Device blocking -b, --blocking-factor=BLOCKS Set record size to BLOCKSx512 bytes. -B, --read-full-records When listing or extracting, accept incomplete input records after end-of-file marker. -i, --ignore-zeros Ignore zeroed blocks in archive. Normally two consecutive 512-blocks filled with zeroes mean EOF and tar stops reading after encountering them. This option instructs it to read further and is useful when reading archives created with the -A option. --record-size=NUMBER Set record size. NUMBER is the number of bytes per record. It must be multiple of 512. It can can be suffixed with a size suffix, e.g. --record-size=10K, for 10 Kilobytes. See the subsection Size suffixes, for a list of valid suffixes. Archive format selection -H, --format=FORMAT Create archive of the given format. Valid formats are: gnu GNU tar 1.13.x format oldgnu GNU format as per tar <= 1.12. pax, posix POSIX 1003.1-2001 (pax) format. ustar POSIX 1003.1-1988 (ustar) format. v7 Old V7 tar format. --old-archive, --portability Same as --format=v7. --pax-option=keyword[[:]=value][,keyword[[:]=value]]... Control pax keywords when creating PAX archives (-H pax). This option is equivalent to the -o option of the pax(1) utility. --posix Same as --format=posix. -V, --label=TEXT Create archive with volume name TEXT. If listing or extracting, use TEXT as a globbing pattern for volume name. Compression options -a, --auto-compress Use archive suffix to determine the compression program. -I, --use-compress-program=COMMAND Filter data through COMMAND. It must accept the -d option, for decompression. The argument can contain command line options. -j, --bzip2 Filter the archive through bzip2(1). -J, --xz Filter the archive through xz(1). --lzip Filter the archive through lzip(1). --lzma Filter the archive through lzma(1). --lzop Filter the archive through lzop(1). --no-auto-compress Do not use archive suffix to determine the compression program. -z, --gzip, --gunzip, --ungzip Filter the archive through gzip(1). -Z, --compress, --uncompress Filter the archive through compress(1). --zstd Filter the archive through zstd(1). Local file selection --add-file=FILE Add FILE to the archive (useful if its name starts with a dash). --backup[=CONTROL] Backup before removal. The CONTROL argument, if supplied, controls the backup policy. Its valid values are: none, off Never make backups. t, numbered Make numbered backups. nil, existing Make numbered backups if numbered backups exist, simple backups otherwise. never, simple Always make simple backups If CONTROL is not given, the value is taken from the VERSION_CONTROL environment variable. If it is not set, existing is assumed. -C, --directory=DIR Change to DIR before performing any operations. This option is order-sensitive, i.e. it affects all options that follow. --exclude=PATTERN Exclude files matching PATTERN, a glob(3)-style wildcard pattern. --exclude-backups Exclude backup and lock files. --exclude-caches Exclude contents of directories containing file CACHEDIR.TAG, except for the tag file itself. --exclude-caches-all Exclude directories containing file CACHEDIR.TAG and the file itself. --exclude-caches-under Exclude everything under directories containing CACHEDIR.TAG --exclude-ignore=FILE Before dumping a directory, see if it contains FILE. If so, read exclusion patterns from this file. The patterns affect only the directory itself. --exclude-ignore-recursive=FILE Same as --exclude-ignore, except that patterns from FILE affect both the directory and all its subdirectories. --exclude-tag=FILE Exclude contents of directories containing FILE, except for FILE itself. --exclude-tag-all=FILE Exclude directories containing FILE. --exclude-tag-under=FILE Exclude everything under directories containing FILE. --exclude-vcs Exclude version control system directories. --exclude-vcs-ignores Exclude files that match patterns read from VCS-specific ignore files. Supported files are: .cvsignore, .gitignore, .bzrignore, and .hgignore. -h, --dereference Follow symlinks; archive and dump the files they point to. --hard-dereference Follow hard links; archive and dump the files they refer to. -K, --starting-file=MEMBER Begin at the given member in the archive. --newer-mtime=DATE Work on files whose data changed after the DATE. If DATE starts with / or . it is taken to be a file name; the mtime of that file is used as the date. --no-null Disable the effect of the previous --null option. --no-recursion Avoid descending automatically in directories. --no-unquote Do not unquote input file or member names. --no-verbatim-files-from Treat each line read from a file list as if it were supplied in the command line. I.e., leading and trailing whitespace is removed and, if the resulting string begins with a dash, it is treated as tar command line option. This is the default behavior. The --no-verbatim-files-from option is provided as a way to restore it after --verbatim-files-from option. This option is positional: it affects all --files-from options that occur after it in, until --verbatim-files-from option or end of line, whichever occurs first. It is implied by the --no-null option. --null Instruct subsequent -T options to read null-terminated names verbatim (disables special handling of names that start with a dash). See also --verbatim-files-from. -N, --newer=DATE, --after-date=DATE Only store files newer than DATE. If DATE starts with / or . it is taken to be a file name; the mtime of that file is used as the date. --one-file-system Stay in local file system when creating archive. -P, --absolute-names Don't strip leading slashes from file names when creating archives. --recursion Recurse into directories (default). --suffix=STRING Backup before removal, override usual suffix. Default suffix is ~, unless overridden by environment variable SIMPLE_BACKUP_SUFFIX. -T, --files-from=FILE Get names to extract or create from FILE. Unless specified otherwise, the FILE must contain a list of names separated by ASCII LF (i.e. one name per line). The names read are handled the same way as command line arguments. They undergo quote removal and word splitting, and any string that starts with a - is handled as tar command line option. If this behavior is undesirable, it can be turned off using the --verbatim-files-from option. The --null option instructs tar that the names in FILE are separated by ASCII NUL character, instead of LF. It is useful if the list is generated by find(1) -print0 predicate. --unquote Unquote file or member names (default). --verbatim-files-from Treat each line obtained from a file list as a file name, even if it starts with a dash. File lists are supplied with the --files-from (-T) option. The default behavior is to handle names supplied in file lists as if they were typed in the command line, i.e. any names starting with a dash are treated as tar options. The --verbatim-files-from option disables this behavior. This option affects all --files-from options that occur after it in the command line. Its effect is reverted by the --no-verbatim-files-from option. This option is implied by the --null option. See also --add-file. -X, --exclude-from=FILE Exclude files matching patterns listed in FILE. File name transformations --strip-components=NUMBER Strip NUMBER leading components from file names on extraction. --transform=EXPRESSION, --xform=EXPRESSION Use sed replace EXPRESSION to transform file names. File name matching options These options affect both exclude and include patterns. --anchored Patterns match file name start. --ignore-case Ignore case. --no-anchored Patterns match after any / (default for exclusion). --no-ignore-case Case sensitive matching (default). --no-wildcards Verbatim string matching. --no-wildcards-match-slash Wildcards do not match /. --wildcards Use wildcards (default for exclusion). --wildcards-match-slash Wildcards match / (default for exclusion). Informative output --checkpoint[=N] Display progress messages every Nth record (default 10). --checkpoint-action=ACTION Run ACTION on each checkpoint. --clamp-mtime Only set time when the file is more recent than what was given with --mtime. --full-time Print file time to its full resolution. --index-file=FILE Send verbose output to FILE. -l, --check-links Print a message if not all links are dumped. --no-quote-chars=STRING Disable quoting for characters from STRING. --quote-chars=STRING Additionally quote characters from STRING. --quoting-style=STYLE Set quoting style for file and member names. Valid values for STYLE are literal, shell, shell-always, c, c-maybe, escape, locale, clocale. -R, --block-number Show block number within archive with each message. --show-omitted-dirs When listing or extracting, list each directory that does not match search criteria. --show-transformed-names, --show-stored-names Show file or archive names after transformation by --strip and --transform options. --totals[=SIGNAL] Print total bytes after processing the archive. If SIGNAL is given, print total bytes when this signal is delivered. Allowed signals are: SIGHUP, SIGQUIT, SIGINT, SIGUSR1, and SIGUSR2. The SIG prefix can be omitted. --utc Print file modification times in UTC. -v, --verbose Verbosely list files processed. Each instance of this option on the command line increases the verbosity level by one. The maximum verbosity level is 3. For a detailed discussion of how various verbosity levels affect tar's output, please refer to GNU Tar Manual, subsection 2.5.2 "The '--verbose' Option". --warning=KEYWORD Enable or disable warning messages identified by KEYWORD. The messages are suppressed if KEYWORD is prefixed with no- and enabled otherwise. Multiple --warning options accumulate. Keywords controlling general tar operation: all Enable all warning messages. This is the default. none Disable all warning messages. filename-with-nuls "%s: file name read contains nul character" alone-zero-block "A lone zero block at %s" Keywords applicable for tar --create: cachedir "%s: contains a cache directory tag %s; %s" file-shrank "%s: File shrank by %s bytes; padding with zeros" xdev "%s: file is on a different filesystem; not dumped" file-ignored "%s: Unknown file type; file ignored" "%s: socket ignored" "%s: door ignored" file-unchanged "%s: file is unchanged; not dumped" ignore-archive "%s: archive cannot contain itself; not dumped" file-removed "%s: File removed before we read it" file-changed "%s: file changed as we read it" failed-read Suppresses warnings about unreadable files or directories. This keyword applies only if used together with the --ignore-failed-read option. Keywords applicable for tar --extract: existing-file "%s: skipping existing file" timestamp "%s: implausibly old time stamp %s" "%s: time stamp %s is %s s in the future" contiguous-cast "Extracting contiguous files as regular files" symlink-cast "Attempting extraction of symbolic links as hard links" unknown-cast "%s: Unknown file type '%c', extracted as normal file" ignore-newer "Current %s is newer or same age" unknown-keyword "Ignoring unknown extended header keyword '%s'" decompress-program Controls verbose description of failures occurring when trying to run alternative decompressor programs. This warning is disabled by default (unless --verbose is used). A common example of what you can get when using this warning is: $ tar --warning=decompress-program -x -f archive.Z tar (child): cannot run compress: No such file or directory tar (child): trying gzip This means that tar first tried to decompress archive.Z using compress, and, when that failed, switched to gzip. record-size "Record size = %lu blocks" Keywords controlling incremental extraction: rename-directory "%s: Directory has been renamed from %s" "%s: Directory has been renamed" new-directory "%s: Directory is new" xdev "%s: directory is on a different device: not purging" bad-dumpdir "Malformed dumpdir: 'X' never used" -w, --interactive, --confirmation Ask for confirmation for every action. Compatibility options -o When creating, same as --old-archive. When extracting, same as --no-same-owner. Size suffixes Suffix Units Byte Equivalent b Blocks SIZE x 512 B Kilobytes SIZE x 1024 c Bytes SIZE G Gigabytes SIZE x 1024^3 K Kilobytes SIZE x 1024 k Kilobytes SIZE x 1024 M Megabytes SIZE x 1024^2 P Petabytes SIZE x 1024^5 T Terabytes SIZE x 1024^4 w Words SIZE x 2 RETURN VALUE top Tar's exit code indicates whether it was able to successfully perform the requested operation, and if not, what kind of error occurred. 0 Successful termination. 1 Some files differ. If tar was invoked with the --compare (--diff, -d) command line option, this means that some files in the archive differ from their disk counterparts. If tar was given one of the --create, --append or --update options, this exit code means that some files were changed while being archived and so the resulting archive does not contain the exact copy of the file set. 2 Fatal error. This means that some fatal, unrecoverable error occurred. If a subprocess that had been invoked by tar exited with a nonzero exit code, tar itself exits with that code as well. This can happen, for example, if a compression option (e.g. -z) was used and the external compressor program failed. Another example is rmt failure during backup to a remote device. SEE ALSO top bzip2(1), compress(1), gzip(1), lzma(1), lzop(1), rmt(8), symlink(7), xz(1), zstd(1). Complete tar manual: run info tar or use emacs(1) info mode to read it. Online copies of GNU tar documentation in various formats can be found at: https://www.gnu.org/software/tar/manual BUG REPORTS top Report bugs to <bug-tar@gnu.org>. COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. COLOPHON top This page is part of the tar (an archiver program) project. Information about the project can be found at http://savannah.gnu.org/projects/tar/. If you have a bug report for this manual page, see http://savannah.gnu.org/bugs/?group=tar. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/tar.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-09-12.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org TAR July 11, 2022 TAR(1) Pages that refer to this page: attr(1), dpkg-deb(1), dpkg-source(1), machinectl(1), rsync(1), st(4), suffixes(7), symlink(7), cupsd-helper(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Create tar archive "dirall.tar" and copy all files from directory tree /tmp/a1 to it Bash Command:<START>find /tmp/a1 -exec tar -rvf dirall.tar {} \;<END>

Create tar archive "foo.tar" and copy all files from directory tree /tmp/a1 to it

find /tmp/a1 | xargs tar cvf foo.tar

['find', 'tar', 'xargs']

Output a Bash command to accomplish the following task. Task: Create tar archive "foo.tar" and copy all files from directory tree /tmp/a1 to it Bash Command:<START>find /tmp/a1 | xargs tar cvf foo.tar<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # tar\n\n> Archiving utility.\n> Often combined with a compression method, such as `gzip` or `bzip2`.\n> More information: <https://www.gnu.org/software/tar>.\n\n- [c]reate an archive and write it to a [f]ile:\n\n`tar cf {{path/to/target.tar}} {{path/to/file1 path/to/file2 ...}}`\n\n- [c]reate a g[z]ipped archive and write it to a [f]ile:\n\n`tar czf {{path/to/target.tar.gz}} {{path/to/file1 path/to/file2 ...}}`\n\n- [c]reate a g[z]ipped archive from a directory using relative paths:\n\n`tar czf {{path/to/target.tar.gz}} --directory={{path/to/directory}} .`\n\n- E[x]tract a (compressed) archive [f]ile into the current directory [v]erbosely:\n\n`tar xvf {{path/to/source.tar[.gz|.bz2|.xz]}}`\n\n- E[x]tract a (compressed) archive [f]ile into the target directory:\n\n`tar xf {{path/to/source.tar[.gz|.bz2|.xz]}} --directory={{path/to/directory}}`\n\n- [c]reate a compressed archive and write it to a [f]ile, using the file extension to [a]utomatically determine the compression program:\n\n`tar caf {{path/to/target.tar.xz}} {{path/to/file1 path/to/file2 ...}}`\n\n- Lis[t] the contents of a tar [f]ile [v]erbosely:\n\n`tar tvf {{path/to/source.tar}}`\n\n- E[x]tract files matching a pattern from an archive [f]ile:\n\n`tar xf {{path/to/source.tar}} --wildcards "{{*.html}}"`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n Task: Create tar archive "foo.tar" and copy all files from directory tree /tmp/a1 to it Bash Command:<START>find /tmp/a1 | xargs tar cvf foo.tar<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. tar(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training tar(1) Linux manual page NAME | SYNOPSIS | NOTE | DESCRIPTION | OPTIONS | RETURN VALUE | SEE ALSO | BUG REPORTS | COPYRIGHT | COLOPHON TAR(1) GNU TAR Manual TAR(1) NAME top tar - an archiving utility SYNOPSIS top Traditional usage tar {A|c|d|r|t|u|x}[GnSkUWOmpsMBiajJzZhPlRvwo] [ARG...] UNIX-style usage tar -A [OPTIONS] -f ARCHIVE ARCHIVE... tar -c [-f ARCHIVE] [OPTIONS] [FILE...] tar -d [-f ARCHIVE] [OPTIONS] [FILE...] tar -r [-f ARCHIVE] [OPTIONS] [FILE...] tar -t [-f ARCHIVE] [OPTIONS] [MEMBER...] tar -u [-f ARCHIVE] [OPTIONS] [FILE...] tar -x [-f ARCHIVE] [OPTIONS] [MEMBER...] GNU-style usage tar {--catenate|--concatenate} [OPTIONS] --file ARCHIVE ARCHIVE... tar --create [--file ARCHIVE] [OPTIONS] [FILE...] tar {--diff|--compare} [--file ARCHIVE] [OPTIONS] [FILE...] tar --delete [--file ARCHIVE] [OPTIONS] [MEMBER...] tar --append [--file ARCHIVE] [OPTIONS] [FILE...] tar --list [--file ARCHIVE] [OPTIONS] [MEMBER...] tar --test-label [--file ARCHIVE] [OPTIONS] [LABEL...] tar --update [--file ARCHIVE] [OPTIONS] [FILE...] tar {--extract|--get} [--file ARCHIVE] [OPTIONS] [MEMBER...] NOTE top This manpage is a short description of GNU tar. For a detailed discussion, including examples and usage recommendations, refer to the GNU Tar Manual available in texinfo format. If the info reader and the tar documentation are properly installed on your system, the command info tar should give you access to the complete manual. You can also view the manual using the info mode in emacs(1), or find it in various formats online at https://www.gnu.org/software/tar/manual If any discrepancies occur between this manpage and the GNU Tar Manual, the later shall be considered the authoritative source. DESCRIPTION top GNU tar is an archiving program designed to store multiple files in a single file (an archive), and to manipulate such archives. The archive can be either a regular file or a device (e.g. a tape drive, hence the name of the program, which stands for tape archiver), which can be located either on the local or on a remote machine. Option styles Options to GNU tar can be given in three different styles. In traditional style, the first argument is a cluster of option letters and all subsequent arguments supply arguments to those options that require them. The arguments are read in the same order as the option letters. Any command line words that remain after all options have been processed are treated as non-option arguments: file or archive member names. For example, the c option requires creating the archive, the v option requests the verbose operation, and the f option takes an argument that sets the name of the archive to operate upon. The following command, written in the traditional style, instructs tar to store all files from the directory /etc into the archive file etc.tar, verbosely listing the files being archived: tar cfv etc.tar /etc In UNIX or short-option style, each option letter is prefixed with a single dash, as in other command line utilities. If an option takes an argument, the argument follows it, either as a separate command line word, or immediately following the option. However, if the option takes an optional argument, the argument must follow the option letter without any intervening whitespace, as in -g/tmp/snar.db. Any number of options not taking arguments can be clustered together after a single dash, e.g. -vkp. An option that takes an argument (whether mandatory or optional) can appear at the end of such a cluster, e.g. -vkpf a.tar. The example command above written in the short-option style could look like: tar -cvf etc.tar /etc or tar -c -v -f etc.tar /etc In GNU or long-option style, each option begins with two dashes and has a meaningful name, consisting of lower-case letters and dashes. When used, the long option can be abbreviated to its initial letters, provided that this does not create ambiguity. Arguments to long options are supplied either as a separate command line word, immediately following the option, or separated from the option by an equals sign with no intervening whitespace. Optional arguments must always use the latter method. Here are several ways of writing the example command in this style: tar --create --file etc.tar --verbose /etc or (abbreviating some options): tar --cre --file=etc.tar --verb /etc The options in all three styles can be intermixed, although doing so with old options is not encouraged. Operation mode The options listed in the table below tell GNU tar what operation it is to perform. Exactly one of them must be given. The meaning of non-option arguments depends on the operation mode requested. -A, --catenate, --concatenate Append archives to the end of another archive. The arguments are treated as the names of archives to append. All archives must be of the same format as the archive they are appended to, otherwise the resulting archive might be unusable with non-GNU implementations of tar. Notice also that when more than one archive is given, the members from archives other than the first one will be accessible in the resulting archive only when using the -i (--ignore-zeros) option. Compressed archives cannot be concatenated. -c, --create Create a new archive. Arguments supply the names of the files to be archived. Directories are archived recursively, unless the --no-recursion option is given. -d, --diff, --compare Find differences between archive and file system. The arguments are optional and specify archive members to compare. If not given, the current working directory is assumed. --delete Delete from the archive. The arguments supply names of the archive members to be removed. At least one argument must be given. This option does not operate on compressed archives. There is no short option equivalent. -r, --append Append files to the end of an archive. Arguments have the same meaning as for -c (--create). -t, --list List the contents of an archive. Arguments are optional. When given, they specify the names of the members to list. --test-label Test the archive volume label and exit. When used without arguments, it prints the volume label (if any) and exits with status 0. When one or more command line arguments are given. tar compares the volume label with each argument. It exits with code 0 if a match is found, and with code 1 otherwise. No output is displayed, unless used together with the -v (--verbose) option. There is no short option equivalent for this option. -u, --update Append files which are newer than the corresponding copy in the archive. Arguments have the same meaning as with the -c and -r options. Notice, that newer files don't replace their old archive copies, but instead are appended to the end of archive. The resulting archive can thus contain several members of the same name, corresponding to various versions of the same file. -x, --extract, --get Extract files from an archive. Arguments are optional. When given, they specify names of the archive members to be extracted. --show-defaults Show built-in defaults for various tar options and exit. -?, --help Display a short option summary and exit. --usage Display a list of available options and exit. --version Print program version and copyright information and exit. OPTIONS top Operation modifiers --check-device Check device numbers when creating incremental archives (default). -g, --listed-incremental=FILE Handle new GNU-format incremental backups. FILE is the name of a snapshot file, where tar stores additional information which is used to decide which files changed since the previous incremental dump and, consequently, must be dumped again. If FILE does not exist when creating an archive, it will be created and all files will be added to the resulting archive (the level 0 dump). To create incremental archives of non-zero level N, you need a copy of the snapshot file created for level N-1, and use it as FILE. When listing or extracting, the actual content of FILE is not inspected, it is needed only due to syntactical requirements. It is therefore common practice to use /dev/null in its place. --hole-detection=METHOD Use METHOD to detect holes in sparse files. This option implies --sparse. Valid values for METHOD are seek and raw. Default is seek with fallback to raw when not applicable. -G, --incremental Handle old GNU-format incremental backups. --ignore-failed-read Do not exit with nonzero on unreadable files. --level=NUMBER Set dump level for a created listed-incremental archive. Currently only --level=0 is meaningful: it instructs tar to truncate the snapshot file before dumping, thereby forcing a level 0 dump. -n, --seek Assume the archive is seekable. Normally tar determines automatically whether the archive can be seeked or not. This option is intended for use in cases when such recognition fails. It takes effect only if the archive is open for reading (e.g. with --list or --extract options). --no-check-device Do not check device numbers when creating incremental archives. --no-seek Assume the archive is not seekable. --occurrence[=N] Process only the Nth occurrence of each file in the archive. This option is valid only when used with one of the following subcommands: --delete, --diff, --extract or --list and when a list of files is given either on the command line or via the -T option. The default N is 1. --restrict Disable the use of some potentially harmful options. --sparse-version=MAJOR[.MINOR] Set which version of the sparse format to use. This option implies --sparse. Valid argument values are 0.0, 0.1, and 1.0. For a detailed discussion of sparse formats, refer to the GNU Tar Manual, appendix D, "Sparse Formats". Using the info reader, it can be accessed running the following command: info tar 'Sparse Formats'. -S, --sparse Handle sparse files efficiently. Some files in the file system may have segments which were actually never written (quite often these are database files created by such systems as DBM). When given this option, tar attempts to determine if the file is sparse prior to archiving it, and if so, to reduce the resulting archive size by not dumping empty parts of the file. Overwrite control These options control tar actions when extracting a file over an existing copy on disk. -k, --keep-old-files Don't replace existing files when extracting. --keep-newer-files Don't replace existing files that are newer than their archive copies. --keep-directory-symlink Don't replace existing symlinks to directories when extracting. --no-overwrite-dir Preserve metadata of existing directories. --one-top-level[=DIR] Extract all files into DIR, or, if used without argument, into a subdirectory named by the base name of the archive (minus standard compression suffixes recognizable by --auto-compress). --overwrite Overwrite existing files when extracting. --overwrite-dir Overwrite metadata of existing directories when extracting (default). --recursive-unlink Recursively remove all files in the directory prior to extracting it. --remove-files Remove files from disk after adding them to the archive. --skip-old-files Don't replace existing files when extracting, silently skip over them. -U, --unlink-first Remove each file prior to extracting over it. -W, --verify Verify the archive after writing it. Output stream selection --ignore-command-error Ignore subprocess exit codes. --no-ignore-command-error Treat non-zero exit codes of children as error (default). -O, --to-stdout Extract files to standard output. --to-command=COMMAND Pipe extracted files to COMMAND. The argument is the pathname of an external program, optionally with command line arguments. The program will be invoked and the contents of the file being extracted supplied to it on its standard input. Additional data will be supplied via the following environment variables: TAR_FILETYPE Type of the file. It is a single letter with the following meaning: f Regular file d Directory l Symbolic link h Hard link b Block device c Character device Currently only regular files are supported. TAR_MODE File mode, an octal number. TAR_FILENAME The name of the file. TAR_REALNAME Name of the file as stored in the archive. TAR_UNAME Name of the file owner. TAR_GNAME Name of the file owner group. TAR_ATIME Time of last access. It is a decimal number, representing seconds since the Epoch. If the archive provides times with nanosecond precision, the nanoseconds are appended to the timestamp after a decimal point. TAR_MTIME Time of last modification. TAR_CTIME Time of last status change. TAR_SIZE Size of the file. TAR_UID UID of the file owner. TAR_GID GID of the file owner. Additionally, the following variables contain information about tar operation mode and the archive being processed: TAR_VERSION GNU tar version number. TAR_ARCHIVE The name of the archive tar is processing. TAR_BLOCKING_FACTOR Current blocking factor, i.e. number of 512-byte blocks in a record. TAR_VOLUME Ordinal number of the volume tar is processing (set if reading a multi-volume archive). TAR_FORMAT Format of the archive being processed. One of: gnu, oldgnu, posix, ustar, v7. TAR_SUBCOMMAND A short option (with a leading dash) describing the operation tar is executing. Handling of file attributes --atime-preserve[=METHOD] Preserve access times on dumped files, either by restoring the times after reading (METHOD=replace, this is the default) or by not setting the times in the first place (METHOD=system). --delay-directory-restore Delay setting modification times and permissions of extracted directories until the end of extraction. Use this option when extracting from an archive which has unusual member ordering. --group=NAME[:GID] Force NAME as group for added files. If GID is not supplied, NAME can be either a user name or numeric GID. In this case the missing part (GID or name) will be inferred from the current host's group database. When used with --group-map=FILE, affects only those files whose owner group is not listed in FILE. --group-map=FILE Read group translation map from FILE. Empty lines are ignored. Comments are introduced with # sign and extend to the end of line. Each non-empty line in FILE defines translation for a single group. It must consist of two fields, delimited by any amount of whitespace: OLDGRP NEWGRP[:NEWGID] OLDGRP is either a valid group name or a GID prefixed with +. Unless NEWGID is supplied, NEWGRP must also be either a valid group name or a +GID. Otherwise, both NEWGRP and NEWGID need not be listed in the system group database. As a result, each input file with owner group OLDGRP will be stored in archive with owner group NEWGRP and GID NEWGID. --mode=CHANGES Force symbolic mode CHANGES for added files. --mtime=DATE-OR-FILE Set mtime for added files. DATE-OR-FILE is either a date/time in almost arbitrary format, or the name of an existing file. In the latter case the mtime of that file will be used. -m, --touch Don't extract file modified time. --no-delay-directory-restore Cancel the effect of the prior --delay-directory-restore option. --no-same-owner Extract files as yourself (default for ordinary users). --no-same-permissions Apply the user's umask when extracting permissions from the archive (default for ordinary users). --numeric-owner Always use numbers for user/group names. --owner=NAME[:UID] Force NAME as owner for added files. If UID is not supplied, NAME can be either a user name or numeric UID. In this case the missing part (UID or name) will be inferred from the current host's user database. When used with --owner-map=FILE, affects only those files whose owner is not listed in FILE. --owner-map=FILE Read owner translation map from FILE. Empty lines are ignored. Comments are introduced with # sign and extend to the end of line. Each non-empty line in FILE defines translation for a single UID. It must consist of two fields, delimited by any amount of whitespace: OLDUSR NEWUSR[:NEWUID] OLDUSR is either a valid user name or a UID prefixed with +. Unless NEWUID is supplied, NEWUSR must also be either a valid user name or a +UID. Otherwise, both NEWUSR and NEWUID need not be listed in the system user database. As a result, each input file owned by OLDUSR will be stored in archive with owner name NEWUSR and UID NEWUID. -p, --preserve-permissions, --same-permissions Set permissions of extracted files to those recorded in the archive (default for superuser). --same-owner Try extracting files with the same ownership as exists in the archive (default for superuser). -s, --preserve-order, --same-order Tell tar that the list of file names to process is sorted in the same order as the files in the archive. --sort=ORDER When creating an archive, sort directory entries according to ORDER, which is one of none, name, or inode. The default is --sort=none, which stores archive members in the same order as returned by the operating system. Using --sort=name ensures the member ordering in the created archive is uniform and reproducible. Using --sort=inode reduces the number of disk seeks made when creating the archive and thus can considerably speed up archivation. This sorting order is supported only if the underlying system provides the necessary information. Extended file attributes --acls Enable POSIX ACLs support. --no-acls Disable POSIX ACLs support. --selinux Enable SELinux context support. --no-selinux Disable SELinux context support. --xattrs Enable extended attributes support. --no-xattrs Disable extended attributes support. --xattrs-exclude=PATTERN Specify the exclude pattern for xattr keys. PATTERN is a globbing pattern, e.g. --xattrs-exclude='user.*' to include only attributes from the user namespace. --xattrs-include=PATTERN Specify the include pattern for xattr keys. PATTERN is a globbing pattern. Device selection and switching -f, --file=ARCHIVE Use archive file or device ARCHIVE. If this option is not given, tar will first examine the environment variable `TAPE'. If it is set, its value will be used as the archive name. Otherwise, tar will assume the compiled-in default. The default value can be inspected either using the --show-defaults option, or at the end of the tar --help output. An archive name that has a colon in it specifies a file or device on a remote machine. The part before the colon is taken as the machine name or IP address, and the part after it as the file or device pathname, e.g.: --file=remotehost:/dev/sr0 An optional username can be prefixed to the hostname, placing a @ sign between them. By default, the remote host is accessed via the rsh(1) command. Nowadays it is common to use ssh(1) instead. You can do so by giving the following command line option: --rsh-command=/usr/bin/ssh The remote machine should have the rmt(8) command installed. If its pathname does not match tar's default, you can inform tar about the correct pathname using the --rmt-command option. --force-local Archive file is local even if it has a colon. -F, --info-script=COMMAND, --new-volume-script=COMMAND Run COMMAND at the end of each tape (implies -M). The command can include arguments. When started, it will inherit tar's environment plus the following variables: TAR_VERSION GNU tar version number. TAR_ARCHIVE The name of the archive tar is processing. TAR_BLOCKING_FACTOR Current blocking factor, i.e. number of 512-byte blocks in a record. TAR_VOLUME Ordinal number of the volume tar is processing (set if reading a multi-volume archive). TAR_FORMAT Format of the archive being processed. One of: gnu, oldgnu, posix, ustar, v7. TAR_SUBCOMMAND A short option (with a leading dash) describing the operation tar is executing. TAR_FD File descriptor which can be used to communicate the new volume name to tar. If the info script fails, tar exits; otherwise, it begins writing the next volume. -L, --tape-length=N Change tape after writing Nx1024 bytes. If N is followed by a size suffix (see the subsection Size suffixes below), the suffix specifies the multiplicative factor to be used instead of 1024. This option implies -M. -M, --multi-volume Create/list/extract multi-volume archive. --rmt-command=COMMAND Use COMMAND instead of rmt when accessing remote archives. See the description of the -f option, above. --rsh-command=COMMAND Use COMMAND instead of rsh when accessing remote archives. See the description of the -f option, above. --volno-file=FILE When this option is used in conjunction with --multi-volume, tar will keep track of which volume of a multi-volume archive it is working in FILE. Device blocking -b, --blocking-factor=BLOCKS Set record size to BLOCKSx512 bytes. -B, --read-full-records When listing or extracting, accept incomplete input records after end-of-file marker. -i, --ignore-zeros Ignore zeroed blocks in archive. Normally two consecutive 512-blocks filled with zeroes mean EOF and tar stops reading after encountering them. This option instructs it to read further and is useful when reading archives created with the -A option. --record-size=NUMBER Set record size. NUMBER is the number of bytes per record. It must be multiple of 512. It can can be suffixed with a size suffix, e.g. --record-size=10K, for 10 Kilobytes. See the subsection Size suffixes, for a list of valid suffixes. Archive format selection -H, --format=FORMAT Create archive of the given format. Valid formats are: gnu GNU tar 1.13.x format oldgnu GNU format as per tar <= 1.12. pax, posix POSIX 1003.1-2001 (pax) format. ustar POSIX 1003.1-1988 (ustar) format. v7 Old V7 tar format. --old-archive, --portability Same as --format=v7. --pax-option=keyword[[:]=value][,keyword[[:]=value]]... Control pax keywords when creating PAX archives (-H pax). This option is equivalent to the -o option of the pax(1) utility. --posix Same as --format=posix. -V, --label=TEXT Create archive with volume name TEXT. If listing or extracting, use TEXT as a globbing pattern for volume name. Compression options -a, --auto-compress Use archive suffix to determine the compression program. -I, --use-compress-program=COMMAND Filter data through COMMAND. It must accept the -d option, for decompression. The argument can contain command line options. -j, --bzip2 Filter the archive through bzip2(1). -J, --xz Filter the archive through xz(1). --lzip Filter the archive through lzip(1). --lzma Filter the archive through lzma(1). --lzop Filter the archive through lzop(1). --no-auto-compress Do not use archive suffix to determine the compression program. -z, --gzip, --gunzip, --ungzip Filter the archive through gzip(1). -Z, --compress, --uncompress Filter the archive through compress(1). --zstd Filter the archive through zstd(1). Local file selection --add-file=FILE Add FILE to the archive (useful if its name starts with a dash). --backup[=CONTROL] Backup before removal. The CONTROL argument, if supplied, controls the backup policy. Its valid values are: none, off Never make backups. t, numbered Make numbered backups. nil, existing Make numbered backups if numbered backups exist, simple backups otherwise. never, simple Always make simple backups If CONTROL is not given, the value is taken from the VERSION_CONTROL environment variable. If it is not set, existing is assumed. -C, --directory=DIR Change to DIR before performing any operations. This option is order-sensitive, i.e. it affects all options that follow. --exclude=PATTERN Exclude files matching PATTERN, a glob(3)-style wildcard pattern. --exclude-backups Exclude backup and lock files. --exclude-caches Exclude contents of directories containing file CACHEDIR.TAG, except for the tag file itself. --exclude-caches-all Exclude directories containing file CACHEDIR.TAG and the file itself. --exclude-caches-under Exclude everything under directories containing CACHEDIR.TAG --exclude-ignore=FILE Before dumping a directory, see if it contains FILE. If so, read exclusion patterns from this file. The patterns affect only the directory itself. --exclude-ignore-recursive=FILE Same as --exclude-ignore, except that patterns from FILE affect both the directory and all its subdirectories. --exclude-tag=FILE Exclude contents of directories containing FILE, except for FILE itself. --exclude-tag-all=FILE Exclude directories containing FILE. --exclude-tag-under=FILE Exclude everything under directories containing FILE. --exclude-vcs Exclude version control system directories. --exclude-vcs-ignores Exclude files that match patterns read from VCS-specific ignore files. Supported files are: .cvsignore, .gitignore, .bzrignore, and .hgignore. -h, --dereference Follow symlinks; archive and dump the files they point to. --hard-dereference Follow hard links; archive and dump the files they refer to. -K, --starting-file=MEMBER Begin at the given member in the archive. --newer-mtime=DATE Work on files whose data changed after the DATE. If DATE starts with / or . it is taken to be a file name; the mtime of that file is used as the date. --no-null Disable the effect of the previous --null option. --no-recursion Avoid descending automatically in directories. --no-unquote Do not unquote input file or member names. --no-verbatim-files-from Treat each line read from a file list as if it were supplied in the command line. I.e., leading and trailing whitespace is removed and, if the resulting string begins with a dash, it is treated as tar command line option. This is the default behavior. The --no-verbatim-files-from option is provided as a way to restore it after --verbatim-files-from option. This option is positional: it affects all --files-from options that occur after it in, until --verbatim-files-from option or end of line, whichever occurs first. It is implied by the --no-null option. --null Instruct subsequent -T options to read null-terminated names verbatim (disables special handling of names that start with a dash). See also --verbatim-files-from. -N, --newer=DATE, --after-date=DATE Only store files newer than DATE. If DATE starts with / or . it is taken to be a file name; the mtime of that file is used as the date. --one-file-system Stay in local file system when creating archive. -P, --absolute-names Don't strip leading slashes from file names when creating archives. --recursion Recurse into directories (default). --suffix=STRING Backup before removal, override usual suffix. Default suffix is ~, unless overridden by environment variable SIMPLE_BACKUP_SUFFIX. -T, --files-from=FILE Get names to extract or create from FILE. Unless specified otherwise, the FILE must contain a list of names separated by ASCII LF (i.e. one name per line). The names read are handled the same way as command line arguments. They undergo quote removal and word splitting, and any string that starts with a - is handled as tar command line option. If this behavior is undesirable, it can be turned off using the --verbatim-files-from option. The --null option instructs tar that the names in FILE are separated by ASCII NUL character, instead of LF. It is useful if the list is generated by find(1) -print0 predicate. --unquote Unquote file or member names (default). --verbatim-files-from Treat each line obtained from a file list as a file name, even if it starts with a dash. File lists are supplied with the --files-from (-T) option. The default behavior is to handle names supplied in file lists as if they were typed in the command line, i.e. any names starting with a dash are treated as tar options. The --verbatim-files-from option disables this behavior. This option affects all --files-from options that occur after it in the command line. Its effect is reverted by the --no-verbatim-files-from option. This option is implied by the --null option. See also --add-file. -X, --exclude-from=FILE Exclude files matching patterns listed in FILE. File name transformations --strip-components=NUMBER Strip NUMBER leading components from file names on extraction. --transform=EXPRESSION, --xform=EXPRESSION Use sed replace EXPRESSION to transform file names. File name matching options These options affect both exclude and include patterns. --anchored Patterns match file name start. --ignore-case Ignore case. --no-anchored Patterns match after any / (default for exclusion). --no-ignore-case Case sensitive matching (default). --no-wildcards Verbatim string matching. --no-wildcards-match-slash Wildcards do not match /. --wildcards Use wildcards (default for exclusion). --wildcards-match-slash Wildcards match / (default for exclusion). Informative output --checkpoint[=N] Display progress messages every Nth record (default 10). --checkpoint-action=ACTION Run ACTION on each checkpoint. --clamp-mtime Only set time when the file is more recent than what was given with --mtime. --full-time Print file time to its full resolution. --index-file=FILE Send verbose output to FILE. -l, --check-links Print a message if not all links are dumped. --no-quote-chars=STRING Disable quoting for characters from STRING. --quote-chars=STRING Additionally quote characters from STRING. --quoting-style=STYLE Set quoting style for file and member names. Valid values for STYLE are literal, shell, shell-always, c, c-maybe, escape, locale, clocale. -R, --block-number Show block number within archive with each message. --show-omitted-dirs When listing or extracting, list each directory that does not match search criteria. --show-transformed-names, --show-stored-names Show file or archive names after transformation by --strip and --transform options. --totals[=SIGNAL] Print total bytes after processing the archive. If SIGNAL is given, print total bytes when this signal is delivered. Allowed signals are: SIGHUP, SIGQUIT, SIGINT, SIGUSR1, and SIGUSR2. The SIG prefix can be omitted. --utc Print file modification times in UTC. -v, --verbose Verbosely list files processed. Each instance of this option on the command line increases the verbosity level by one. The maximum verbosity level is 3. For a detailed discussion of how various verbosity levels affect tar's output, please refer to GNU Tar Manual, subsection 2.5.2 "The '--verbose' Option". --warning=KEYWORD Enable or disable warning messages identified by KEYWORD. The messages are suppressed if KEYWORD is prefixed with no- and enabled otherwise. Multiple --warning options accumulate. Keywords controlling general tar operation: all Enable all warning messages. This is the default. none Disable all warning messages. filename-with-nuls "%s: file name read contains nul character" alone-zero-block "A lone zero block at %s" Keywords applicable for tar --create: cachedir "%s: contains a cache directory tag %s; %s" file-shrank "%s: File shrank by %s bytes; padding with zeros" xdev "%s: file is on a different filesystem; not dumped" file-ignored "%s: Unknown file type; file ignored" "%s: socket ignored" "%s: door ignored" file-unchanged "%s: file is unchanged; not dumped" ignore-archive "%s: archive cannot contain itself; not dumped" file-removed "%s: File removed before we read it" file-changed "%s: file changed as we read it" failed-read Suppresses warnings about unreadable files or directories. This keyword applies only if used together with the --ignore-failed-read option. Keywords applicable for tar --extract: existing-file "%s: skipping existing file" timestamp "%s: implausibly old time stamp %s" "%s: time stamp %s is %s s in the future" contiguous-cast "Extracting contiguous files as regular files" symlink-cast "Attempting extraction of symbolic links as hard links" unknown-cast "%s: Unknown file type '%c', extracted as normal file" ignore-newer "Current %s is newer or same age" unknown-keyword "Ignoring unknown extended header keyword '%s'" decompress-program Controls verbose description of failures occurring when trying to run alternative decompressor programs. This warning is disabled by default (unless --verbose is used). A common example of what you can get when using this warning is: $ tar --warning=decompress-program -x -f archive.Z tar (child): cannot run compress: No such file or directory tar (child): trying gzip This means that tar first tried to decompress archive.Z using compress, and, when that failed, switched to gzip. record-size "Record size = %lu blocks" Keywords controlling incremental extraction: rename-directory "%s: Directory has been renamed from %s" "%s: Directory has been renamed" new-directory "%s: Directory is new" xdev "%s: directory is on a different device: not purging" bad-dumpdir "Malformed dumpdir: 'X' never used" -w, --interactive, --confirmation Ask for confirmation for every action. Compatibility options -o When creating, same as --old-archive. When extracting, same as --no-same-owner. Size suffixes Suffix Units Byte Equivalent b Blocks SIZE x 512 B Kilobytes SIZE x 1024 c Bytes SIZE G Gigabytes SIZE x 1024^3 K Kilobytes SIZE x 1024 k Kilobytes SIZE x 1024 M Megabytes SIZE x 1024^2 P Petabytes SIZE x 1024^5 T Terabytes SIZE x 1024^4 w Words SIZE x 2 RETURN VALUE top Tar's exit code indicates whether it was able to successfully perform the requested operation, and if not, what kind of error occurred. 0 Successful termination. 1 Some files differ. If tar was invoked with the --compare (--diff, -d) command line option, this means that some files in the archive differ from their disk counterparts. If tar was given one of the --create, --append or --update options, this exit code means that some files were changed while being archived and so the resulting archive does not contain the exact copy of the file set. 2 Fatal error. This means that some fatal, unrecoverable error occurred. If a subprocess that had been invoked by tar exited with a nonzero exit code, tar itself exits with that code as well. This can happen, for example, if a compression option (e.g. -z) was used and the external compressor program failed. Another example is rmt failure during backup to a remote device. SEE ALSO top bzip2(1), compress(1), gzip(1), lzma(1), lzop(1), rmt(8), symlink(7), xz(1), zstd(1). Complete tar manual: run info tar or use emacs(1) info mode to read it. Online copies of GNU tar documentation in various formats can be found at: https://www.gnu.org/software/tar/manual BUG REPORTS top Report bugs to <bug-tar@gnu.org>. COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. COLOPHON top This page is part of the tar (an archiver program) project. Information about the project can be found at http://savannah.gnu.org/projects/tar/. If you have a bug report for this manual page, see http://savannah.gnu.org/bugs/?group=tar. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/tar.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-09-12.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org TAR July 11, 2022 TAR(1) Pages that refer to this page: attr(1), dpkg-deb(1), dpkg-source(1), machinectl(1), rsync(1), st(4), suffixes(7), symlink(7), cupsd-helper(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Create tar archive "foo.tar" and copy all files from directory tree /tmp/a1 to it Bash Command:<START>find /tmp/a1 | xargs tar cvf foo.tar<END>

Create the directory '.npm-global' in the user's home directory(~).

mkdir ~/.npm-global

['mkdir']

Output a Bash command to accomplish the following task. Task: Create the directory '.npm-global' in the user's home directory(~). Bash Command:<START>mkdir ~/.npm-global<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mkdir\n\n> Create directories and set their permissions.\n> More information: <https://www.gnu.org/software/coreutils/mkdir>.\n\n- Create specific directories:\n\n`mkdir {{path/to/directory1 path/to/directory2 ...}}`\n\n- Create specific directories and their [p]arents if needed:\n\n`mkdir -p {{path/to/directory1 path/to/directory2 ...}}`\n\n- Create directories with specific permissions:\n\n`mkdir -m {{rwxrw-r--}} {{path/to/directory1 path/to/directory2 ...}}`\n Task: Create the directory '.npm-global' in the user's home directory(~). Bash Command:<START>mkdir ~/.npm-global<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mkdir(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mkdir(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKDIR(1) User Commands MKDIR(1) NAME top mkdir - make directories SYNOPSIS top mkdir [OPTION]... DIRECTORY... DESCRIPTION top Create the DIRECTORY(ies), if they do not already exist. Mandatory arguments to long options are mandatory for short options too. -m, --mode=MODE set file mode (as in chmod), not a=rwx - umask -p, --parents no error if existing, make parent directories as needed, with their file modes unaffected by any -m option. -v, --verbose print a message for each created directory -Z set SELinux security context of each created directory to the default type --context[=CTX] like -Z, or if CTX is specified then set the SELinux or SMACK security context to CTX --help display this help and exit --version output version information and exit AUTHOR top Written by David MacKenzie. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkdir(2) Full documentation <https://www.gnu.org/software/coreutils/mkdir> or available locally via: info '(coreutils) mkdir invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKDIR(1) Pages that refer to this page: systemd-mount(1), mkdir(2), cpuset(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Create the directory '.npm-global' in the user's home directory(~). Bash Command:<START>mkdir ~/.npm-global<END>

Create the directory '.npm-packages' in the user's home directory($HOME)

mkdir "${HOME}/.npm-packages"

['mkdir']

Output a Bash command to accomplish the following task. Task: Create the directory '.npm-packages' in the user's home directory($HOME) Bash Command:<START>mkdir "${HOME}/.npm-packages"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mkdir\n\n> Create directories and set their permissions.\n> More information: <https://www.gnu.org/software/coreutils/mkdir>.\n\n- Create specific directories:\n\n`mkdir {{path/to/directory1 path/to/directory2 ...}}`\n\n- Create specific directories and their [p]arents if needed:\n\n`mkdir -p {{path/to/directory1 path/to/directory2 ...}}`\n\n- Create directories with specific permissions:\n\n`mkdir -m {{rwxrw-r--}} {{path/to/directory1 path/to/directory2 ...}}`\n Task: Create the directory '.npm-packages' in the user's home directory($HOME) Bash Command:<START>mkdir "${HOME}/.npm-packages"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mkdir(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mkdir(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKDIR(1) User Commands MKDIR(1) NAME top mkdir - make directories SYNOPSIS top mkdir [OPTION]... DIRECTORY... DESCRIPTION top Create the DIRECTORY(ies), if they do not already exist. Mandatory arguments to long options are mandatory for short options too. -m, --mode=MODE set file mode (as in chmod), not a=rwx - umask -p, --parents no error if existing, make parent directories as needed, with their file modes unaffected by any -m option. -v, --verbose print a message for each created directory -Z set SELinux security context of each created directory to the default type --context[=CTX] like -Z, or if CTX is specified then set the SELinux or SMACK security context to CTX --help display this help and exit --version output version information and exit AUTHOR top Written by David MacKenzie. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkdir(2) Full documentation <https://www.gnu.org/software/coreutils/mkdir> or available locally via: info '(coreutils) mkdir invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKDIR(1) Pages that refer to this page: systemd-mount(1), mkdir(2), cpuset(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Create the directory '.npm-packages' in the user's home directory($HOME) Bash Command:<START>mkdir "${HOME}/.npm-packages"<END>

Creates 5-letter random file name and saves it in 'rand_str' variable.

rand_str="$(mktemp --dry-run XXXXX)"

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates 5-letter random file name and saves it in 'rand_str' variable. Bash Command:<START>rand_str="$(mktemp --dry-run XXXXX)"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates 5-letter random file name and saves it in 'rand_str' variable. Bash Command:<START>rand_str="$(mktemp --dry-run XXXXX)"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates 5-letter random file name and saves it in 'rand_str' variable. Bash Command:<START>rand_str="$(mktemp --dry-run XXXXX)"<END>

Creates alias for network interface 'eth0' with IP address '192.0.2.55' and network mask '255.255.255.255'.

ifconfig eth0:fakenfs 192.0.2.55 netmask 255.255.255.255

['ifconfig']

Output a Bash command to accomplish the following task. Task: Creates alias for network interface 'eth0' with IP address '192.0.2.55' and network mask '255.255.255.255'. Bash Command:<START>ifconfig eth0:fakenfs 192.0.2.55 netmask 255.255.255.255<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # ifconfig\n\n> Network Interface Configurator.\n> More information: <https://net-tools.sourceforge.io/man/ifconfig.8.html>.\n\n- View network settings of an Ethernet adapter:\n\n`ifconfig eth0`\n\n- Display details of all interfaces, including disabled interfaces:\n\n`ifconfig -a`\n\n- Disable eth0 interface:\n\n`ifconfig eth0 down`\n\n- Enable eth0 interface:\n\n`ifconfig eth0 up`\n\n- Assign IP address to eth0 interface:\n\n`ifconfig eth0 {{ip_address}}`\n Task: Creates alias for network interface 'eth0' with IP address '192.0.2.55' and network mask '255.255.255.255'. Bash Command:<START>ifconfig eth0:fakenfs 192.0.2.55 netmask 255.255.255.255<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: ifconfig(8) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training ifconfig(8) Linux manual page NAME | SYNOPSIS | DESCRIPTION | Address Families | OPTIONS | NOTES | FILES | BUGS | SEE ALSO | AUTHORS | COLOPHON IFCONFIG(8) Linux System Administrator's Manual IFCONFIG(8) NAME top ifconfig - configure a network interface SYNOPSIS top ifconfig [-v] [-a] [-s] [interface] ifconfig [-v] interface [aftype] options | address ... DESCRIPTION top Ifconfig is used to configure the kernel-resident network interfaces. It is used at boot time to set up interfaces as necessary. After that, it is usually only needed when debugging or when system tuning is needed. If no arguments are given, ifconfig displays the status of the currently active interfaces. If a single interface argument is given, it displays the status of the given interface only; if a single -a argument is given, it displays the status of all interfaces, even those that are down. Otherwise, it configures an interface. Address Families top If the first argument after the interface name is recognized as the name of a supported address family, that address family is used for decoding and displaying all protocol addresses. Currently supported address families include inet (TCP/IP, default), inet6 (IPv6), ax25 (AMPR Packet Radio), ddp (Appletalk Phase 2), ipx (Novell IPX) and netrom (AMPR Packet radio). All numbers supplied as parts in IPv4 dotted decimal notation may be decimal, octal, or hexadecimal, as specified in the ISO C standard (that is, a leading 0x or 0X implies hexadecimal; otherwise, a leading '0' implies octal; otherwise, the number is interpreted as decimal). Use of hexadecimal and octal numbers is not RFC-compliant and therefore its use is discouraged. OPTIONS top -a display all interfaces which are currently available, even if down -s display a short list (like netstat -i) -v be more verbose for some error conditions interface The name of the interface. This is usually a driver name followed by a unit number, for example eth0 for the first Ethernet interface. If your kernel supports alias interfaces, you can specify them with syntax like eth0:0 for the first alias of eth0. You can use them to assign more addresses. To delete an alias interface use ifconfig eth0:0 down. Note: for every scope (i.e. same net with address/netmask combination) all aliases are deleted, if you delete the first (primary). up This flag causes the interface to be activated. It is implicitly specified if an address is assigned to the interface; you can suppress this behavior when using an alias interface by appending an - to the alias (e.g. eth0:0-). It is also suppressed when using the IPv4 0.0.0.0 address as the kernel will use this to implicitly delete alias interfaces. down This flag causes the driver for this interface to be shut down. [-]arp Enable or disable the use of the ARP protocol on this interface. [-]promisc Enable or disable the promiscuous mode of the interface. If selected, all packets on the network will be received by the interface. [-]allmulti Enable or disable all-multicast mode. If selected, all multicast packets on the network will be received by the interface. mtu N This parameter sets the Maximum Transfer Unit (MTU) of an interface. dstaddr addr Set the remote IP address for a point-to-point link (such as PPP). This keyword is now obsolete; use the pointopoint keyword instead. netmask addr Set the IP network mask for this interface. This value defaults to the usual class A, B or C network mask (as derived from the interface IP address), but it can be set to any value. add addr/prefixlen Add an IPv6 address to an interface. del addr/prefixlen Remove an IPv6 address from an interface. tunnel ::aa.bb.cc.dd Create a new SIT (IPv6-in-IPv4) device, tunnelling to the given destination. irq addr Set the interrupt line used by this device. Not all devices can dynamically change their IRQ setting. io_addr addr Set the start address in I/O space for this device. mem_start addr Set the start address for shared memory used by this device. Only a few devices need this. media type Set the physical port or medium type to be used by the device. Not all devices can change this setting, and those that can vary in what values they support. Typical values for type are 10base2 (thin Ethernet), 10baseT (twisted-pair 10Mbps Ethernet), AUI (external transceiver) and so on. The special medium type of auto can be used to tell the driver to auto-sense the media. Again, not all drivers can do this. [-]broadcast [addr] If the address argument is given, set the protocol broadcast address for this interface. Otherwise, set (or clear) the IFF_BROADCAST flag for the interface. [-]pointopoint [addr] This keyword enables the point-to-point mode of an interface, meaning that it is a direct link between two machines with nobody else listening on it. If the address argument is also given, set the protocol address of the other side of the link, just like the obsolete dstaddr keyword does. Otherwise, set or clear the IFF_POINTOPOINT flag for the interface. hw class address Set the hardware address of this interface, if the device driver supports this operation. The keyword must be followed by the name of the hardware class and the printable ASCII equivalent of the hardware address. Hardware classes currently supported include ether (Ethernet), ax25 (AMPR AX.25), ARCnet and netrom (AMPR NET/ROM). multicast Set the multicast flag on the interface. This should not normally be needed as the drivers set the flag correctly themselves. address The IP address to be assigned to this interface. txqueuelen length Set the length of the transmit queue of the device. It is useful to set this to small values for slower devices with a high latency (modem links, ISDN) to prevent fast bulk transfers from disturbing interactive traffic like telnet too much. name newname Change the name of this interface to newname. The interface must be shut down first. NOTES top Since kernel release 2.2 there are no explicit interface statistics for alias interfaces anymore. The statistics printed for the original address are shared with all alias addresses on the same device. If you want per-address statistics you should add explicit accounting rules for the address using the iptables(8) command. Since net-tools 1.60-4 ifconfig is printing byte counters and human readable counters with IEC 60027-2 units. So 1 KiB are 2^10 byte. Note, the numbers are truncated to one decimal (which can by quite a large error if you consider 0.1 PiB is 112.589.990.684.262 bytes :) Interrupt problems with Ethernet device drivers fail with EAGAIN (SIOCSIIFLAGS: Resource temporarily unavailable) it is most likely a interrupt conflict. See http://www.scyld.com/expert/irq-conflict.html for more information. FILES top /proc/net/dev /proc/net/if_inet6 BUGS top Ifconfig uses the ioctl access method to get the full address information, which limits hardware addresses to 8 bytes. Because Infiniband hardware address has 20 bytes, only the first 8 bytes are displayed correctly. Please use ip link command from iproute2 package to display link layer informations including the hardware address. While appletalk DDP and IPX addresses will be displayed they cannot be altered by this command. SEE ALSO top route(8), netstat(8), arp(8), rarp(8), iptables(8), ifup(8), interfaces(5) http://physics.nist.gov/cuu/Units/binary.html - Prefixes for binary multiples AUTHORS top Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org> Alan Cox, <Alan.Cox@linux.org> Phil Blundell, <Philip.Blundell@pobox.com> Andi Kleen Bernd Eckenfels, <net-tools@lina.inka.de> COLOPHON top This page is part of the net-tools (networking utilities) project. Information about the project can be found at http://net-tools.sourceforge.net/. If you have a bug report for this manual page, see http://net-tools.sourceforge.net/. This page was obtained from the project's upstream Git repository git://git.code.sf.net/p/net-tools/code on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-06-29.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org net-tools 2008-10-03 IFCONFIG(8) Pages that refer to this page: getifaddrs(3), if_nameindex(3), if_nametoindex(3), sk98lin(4), wavelan(4), proc(5), arp(8), netstat(8), plipconfig(8), rarp(8), route(8), tc-bfifo(8), tc-pfifo_fast(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates alias for network interface 'eth0' with IP address '192.0.2.55' and network mask '255.255.255.255'. Bash Command:<START>ifconfig eth0:fakenfs 192.0.2.55 netmask 255.255.255.255<END>

Creates file by template 'aws-sync-XXXXX' in a current folder and stores file name in a 'dir' variable.

dir="$(mktemp aws-sync-XXXXX)"

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates file by template 'aws-sync-XXXXX' in a current folder and stores file name in a 'dir' variable. Bash Command:<START>dir="$(mktemp aws-sync-XXXXX)"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates file by template 'aws-sync-XXXXX' in a current folder and stores file name in a 'dir' variable. Bash Command:<START>dir="$(mktemp aws-sync-XXXXX)"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates file by template 'aws-sync-XXXXX' in a current folder and stores file name in a 'dir' variable. Bash Command:<START>dir="$(mktemp aws-sync-XXXXX)"<END>

Creates full path with parents, that matches to folder path extracted from $f variable.

mkdir -p -- "$(dirname -- "$f")"

['dirname', 'mkdir']

Output a Bash command to accomplish the following task. Task: Creates full path with parents, that matches to folder path extracted from $f variable. Bash Command:<START>mkdir -p -- "$(dirname -- "$f")"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # dirname\n\n> Calculates the parent directory of a file or directory path.\n> More information: <https://www.gnu.org/software/coreutils/dirname>.\n\n- Calculate the parent directory of a given path:\n\n`dirname {{path/to/file_or_directory}}`\n\n- Calculate the parent directory of multiple paths:\n\n`dirname {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n\n- Delimit output with a NUL character instead of a newline (useful when combining with `xargs`):\n\n`dirname --zero {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n # mkdir\n\n> Create directories and set their permissions.\n> More information: <https://www.gnu.org/software/coreutils/mkdir>.\n\n- Create specific directories:\n\n`mkdir {{path/to/directory1 path/to/directory2 ...}}`\n\n- Create specific directories and their [p]arents if needed:\n\n`mkdir -p {{path/to/directory1 path/to/directory2 ...}}`\n\n- Create directories with specific permissions:\n\n`mkdir -m {{rwxrw-r--}} {{path/to/directory1 path/to/directory2 ...}}`\n Task: Creates full path with parents, that matches to folder path extracted from $f variable. Bash Command:<START>mkdir -p -- "$(dirname -- "$f")"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: dirname(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training dirname(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | EXAMPLES | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON DIRNAME(1) User Commands DIRNAME(1) NAME top dirname - strip last component from file name SYNOPSIS top dirname [OPTION] NAME... DESCRIPTION top Output each NAME with its last non-slash component and trailing slashes removed; if NAME contains no /'s, output '.' (meaning the current directory). -z, --zero end each output line with NUL, not newline --help display this help and exit --version output version information and exit EXAMPLES top dirname /usr/bin/ -> "/usr" dirname dir1/str dir2/str -> "dir1" followed by "dir2" dirname stdio.h -> "." AUTHOR top Written by David MacKenzie and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top basename(1), readlink(1) Full documentation <https://www.gnu.org/software/coreutils/dirname> or available locally via: info '(coreutils) dirname invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 DIRNAME(1) Pages that refer to this page: basename(1), basename(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. mkdir(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mkdir(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKDIR(1) User Commands MKDIR(1) NAME top mkdir - make directories SYNOPSIS top mkdir [OPTION]... DIRECTORY... DESCRIPTION top Create the DIRECTORY(ies), if they do not already exist. Mandatory arguments to long options are mandatory for short options too. -m, --mode=MODE set file mode (as in chmod), not a=rwx - umask -p, --parents no error if existing, make parent directories as needed, with their file modes unaffected by any -m option. -v, --verbose print a message for each created directory -Z set SELinux security context of each created directory to the default type --context[=CTX] like -Z, or if CTX is specified then set the SELinux or SMACK security context to CTX --help display this help and exit --version output version information and exit AUTHOR top Written by David MacKenzie. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkdir(2) Full documentation <https://www.gnu.org/software/coreutils/mkdir> or available locally via: info '(coreutils) mkdir invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKDIR(1) Pages that refer to this page: systemd-mount(1), mkdir(2), cpuset(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates full path with parents, that matches to folder path extracted from $f variable. Bash Command:<START>mkdir -p -- "$(dirname -- "$f")"<END>

Creates path as current folder path and folder that contains $0 file, and saves result in 'script_dir' variable.

set script_dir = `pwd`/`dirname $0`

['pwd', 'set', 'dirname']

Output a Bash command to accomplish the following task. Task: Creates path as current folder path and folder that contains $0 file, and saves result in 'script_dir' variable. Bash Command:<START>set script_dir = `pwd`/`dirname $0`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # pwd\n\n> Print name of current/working directory.\n> More information: <https://www.gnu.org/software/coreutils/pwd>.\n\n- Print the current directory:\n\n`pwd`\n\n- Print the current directory, and resolve all symlinks (i.e. show the "physical" path):\n\n`pwd --physical`\n\n- Print the current logical directory:\n\n`pwd --logical`\n # set\n\n> Toggle shell options or set the values of positional parameters.\n> More information: <https://manned.org/set.1posix>.\n\n- Display the names and values of shell variables:\n\n`set`\n\n- Export newly initialized variables to child processes:\n\n`set -a`\n\n- Write formatted messages to `stderr` when jobs finish:\n\n`set -b`\n\n- Write and edit text in the command line with `vi`-like keybindings (e.g. `yy`):\n\n`set -o {{vi}}`\n\n- Exit the shell when (some) commands fail:\n\n`set -e`\n # dirname\n\n> Calculates the parent directory of a file or directory path.\n> More information: <https://www.gnu.org/software/coreutils/dirname>.\n\n- Calculate the parent directory of a given path:\n\n`dirname {{path/to/file_or_directory}}`\n\n- Calculate the parent directory of multiple paths:\n\n`dirname {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n\n- Delimit output with a NUL character instead of a newline (useful when combining with `xargs`):\n\n`dirname --zero {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Creates path as current folder path and folder that contains $0 file, and saves result in 'script_dir' variable. Bash Command:<START>set script_dir = `pwd`/`dirname $0`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: pwd(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training pwd(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON PWD(1) User Commands PWD(1) NAME top pwd - print name of current/working directory SYNOPSIS top pwd [OPTION]... DESCRIPTION top Print the full filename of the current working directory. -L, --logical use PWD from environment, even if it contains symlinks -P, --physical avoid all symlinks --help display this help and exit --version output version information and exit If no option is specified, -P is assumed. NOTE: your shell may have its own version of pwd, which usually supersedes the version described here. Please refer to your shell's documentation for details about the options it supports. AUTHOR top Written by Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top getcwd(3) Full documentation <https://www.gnu.org/software/coreutils/pwd> or available locally via: info '(coreutils) pwd invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 PWD(1) Pages that refer to this page: getcwd(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. set(1p) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training set(1p) Linux manual page PROLOG | NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | STDIN | INPUT FILES | ENVIRONMENT VARIABLES | ASYNCHRONOUS EVENTS | STDOUT | STDERR | OUTPUT FILES | EXTENDED DESCRIPTION | EXIT STATUS | CONSEQUENCES OF ERRORS | APPLICATION USAGE | EXAMPLES | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT SET(1P) POSIX Programmer's Manual SET(1P) PROLOG top This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux. NAME top set set or unset options and positional parameters SYNOPSIS top set [-abCefhmnuvx] [-o option] [argument...] set [+abCefhmnuvx] [+o option] [argument...] set -- [argument...] set -o set +o DESCRIPTION top If no options or arguments are specified, set shall write the names and values of all shell variables in the collation sequence of the current locale. Each name shall start on a separate line, using the format: "%s=%s\n", <name>, <value> The value string shall be written with appropriate quoting; see the description of shell quoting in Section 2.2, Quoting. The output shall be suitable for reinput to the shell, setting or resetting, as far as possible, the variables that are currently set; read-only variables cannot be reset. When options are specified, they shall set or unset attributes of the shell, as described below. When arguments are specified, they cause positional parameters to be set or unset, as described below. Setting or unsetting attributes and positional parameters are not necessarily related actions, but they can be combined in a single invocation of set. The set special built-in shall support the Base Definitions volume of POSIX.12017, Section 12.2, Utility Syntax Guidelines except that options can be specified with either a leading <hyphen-minus> (meaning enable the option) or <plus-sign> (meaning disable it) unless otherwise specified. Implementations shall support the options in the following list in both their <hyphen-minus> and <plus-sign> forms. These options can also be specified as options to sh. -a When this option is on, the export attribute shall be set for each variable to which an assignment is performed; see the Base Definitions volume of POSIX.12017, Section 4.23, Variable Assignment. If the assignment precedes a utility name in a command, the export attribute shall not persist in the current execution environment after the utility completes, with the exception that preceding one of the special built-in utilities causes the export attribute to persist after the built-in has completed. If the assignment does not precede a utility name in the command, or if the assignment is a result of the operation of the getopts or read utilities, the export attribute shall persist until the variable is unset. -b This option shall be supported if the implementation supports the User Portability Utilities option. It shall cause the shell to notify the user asynchronously of background job completions. The following message is written to standard error: "[%d]%c %s%s\n", <job-number>, <current>, <status>, <job-name> where the fields shall be as follows: <current> The character '+' identifies the job that would be used as a default for the fg or bg utilities; this job can also be specified using the job_id "%+" or "%%". The character '-' identifies the job that would become the default if the current default job were to exit; this job can also be specified using the job_id "%-". For other jobs, this field is a <space>. At most one job can be identified with '+' and at most one job can be identified with '-'. If there is any suspended job, then the current job shall be a suspended job. If there are at least two suspended jobs, then the previous job also shall be a suspended job. <job-number> A number that can be used to identify the process group to the wait, fg, bg, and kill utilities. Using these utilities, the job can be identified by prefixing the job number with '%'. <status> Unspecified. <job-name> Unspecified. When the shell notifies the user a job has been completed, it may remove the job's process ID from the list of those known in the current shell execution environment; see Section 2.9.3.1, Examples. Asynchronous notification shall not be enabled by default. -C (Uppercase C.) Prevent existing files from being overwritten by the shell's '>' redirection operator (see Section 2.7.2, Redirecting Output); the ">|" redirection operator shall override this noclobber option for an individual file. -e When this option is on, when any command fails (for any of the reasons listed in Section 2.8.1, Consequences of Shell Errors or by returning an exit status greater than zero), the shell immediately shall exit, as if by executing the exit special built-in utility with no arguments, with the following exceptions: 1. The failure of any individual command in a multi- command pipeline shall not cause the shell to exit. Only the failure of the pipeline itself shall be considered. 2. The -e setting shall be ignored when executing the compound list following the while, until, if, or elif reserved word, a pipeline beginning with the ! reserved word, or any command of an AND-OR list other than the last. 3. If the exit status of a compound command other than a subshell command was the result of a failure while -e was being ignored, then -e shall not apply to this command. This requirement applies to the shell environment and each subshell environment separately. For example, in: set -e; (false; echo one) | cat; echo two the false command causes the subshell to exit without executing echo one; however, echo two is executed because the exit status of the pipeline (false; echo one) | cat is zero. -f The shell shall disable pathname expansion. -h Locate and remember utilities invoked by functions as those functions are defined (the utilities are normally located when the function is executed). -m This option shall be supported if the implementation supports the User Portability Utilities option. All jobs shall be run in their own process groups. Immediately before the shell issues a prompt after completion of the background job, a message reporting the exit status of the background job shall be written to standard error. If a foreground job stops, the shell shall write a message to standard error to that effect, formatted as described by the jobs utility. In addition, if a job changes status other than exiting (for example, if it stops for input or output or is stopped by a SIGSTOP signal), the shell shall write a similar message immediately prior to writing the next prompt. This option is enabled by default for interactive shells. -n The shell shall read commands but does not execute them; this can be used to check for shell script syntax errors. An interactive shell may ignore this option. -o Write the current settings of the options to standard output in an unspecified format. +o Write the current option settings to standard output in a format that is suitable for reinput to the shell as commands that achieve the same options settings. -o option This option is supported if the system supports the User Portability Utilities option. It shall set various options, many of which shall be equivalent to the single option letters. The following values of option shall be supported: allexport Equivalent to -a. errexit Equivalent to -e. ignoreeof Prevent an interactive shell from exiting on end- of-file. This setting prevents accidental logouts when <control>D is entered. A user shall explicitly exit to leave the interactive shell. monitor Equivalent to -m. This option is supported if the system supports the User Portability Utilities option. noclobber Equivalent to -C (uppercase C). noglob Equivalent to -f. noexec Equivalent to -n. nolog Prevent the entry of function definitions into the command history; see Command History List. notify Equivalent to -b. nounset Equivalent to -u. verbose Equivalent to -v. vi Allow shell command line editing using the built- in vi editor. Enabling vi mode shall disable any other command line editing mode provided as an implementation extension. It need not be possible to set vi mode on for certain block-mode terminals. xtrace Equivalent to -x. -u When the shell tries to expand an unset parameter other than the '@' and '*' special parameters, it shall write a message to standard error and the expansion shall fail with the consequences specified in Section 2.8.1, Consequences of Shell Errors. -v The shell shall write its input to standard error as it is read. -x The shell shall write to standard error a trace for each command after it expands the command and before it executes it. It is unspecified whether the command that turns tracing off is traced. The default for all these options shall be off (unset) unless stated otherwise in the description of the option or unless the shell was invoked with them on; see sh. The remaining arguments shall be assigned in order to the positional parameters. The special parameter '#' shall be set to reflect the number of positional parameters. All positional parameters shall be unset before any new values are assigned. If the first argument is '-', the results are unspecified. The special argument "--" immediately following the set command name can be used to delimit the arguments if the first argument begins with '+' or '-', or to prevent inadvertent listing of all shell variables when there are no arguments. The command set -- without argument shall unset all positional parameters and set the special parameter '#' to zero. OPTIONS top See the DESCRIPTION. OPERANDS top See the DESCRIPTION. STDIN top Not used. INPUT FILES top None. ENVIRONMENT VARIABLES top None. ASYNCHRONOUS EVENTS top Default. STDOUT top See the DESCRIPTION. STDERR top The standard error shall be used only for diagnostic messages. OUTPUT FILES top None. EXTENDED DESCRIPTION top None. EXIT STATUS top 0 Successful completion. >0 An invalid option was specified, or an error occurred. CONSEQUENCES OF ERRORS top Default. The following sections are informative. APPLICATION USAGE top Application writers should avoid relying on set -e within functions. For example, in the following script: set -e start() { some_server echo some_server started successfully } start || echo >&2 some_server failed the -e setting is ignored within the function body (because the function is a command in an AND-OR list other than the last). Therefore, if some_server fails, the function carries on to echo "some_serverstartedsuccessfully", and the exit status of the function is zero (which means "some_serverfailed" is not output). EXAMPLES top Write out all variables and their values: set Set $1, $2, and $3 and set "$#" to 3: set c a b Turn on the -x and -v options: set -xv Unset all positional parameters: set -- Set $1 to the value of x, even if it begins with '-' or '+': set -- "$x" Set the positional parameters to the expansion of x, even if x expands with a leading '-' or '+': set -- $x RATIONALE top The set -- form is listed specifically in the SYNOPSIS even though this usage is implied by the Utility Syntax Guidelines. The explanation of this feature removes any ambiguity about whether the set -- form might be misinterpreted as being equivalent to set without any options or arguments. The functionality of this form has been adopted from the KornShell. In System V, set -- only unsets parameters if there is at least one argument; the only way to unset all parameters is to use shift. Using the KornShell version should not affect System V scripts because there should be no reason to issue it without arguments deliberately; if it were issued as, for example: set -- "$@" and there were in fact no arguments resulting from "$@", unsetting the parameters would have no result. The set + form in early proposals was omitted as being an unnecessary duplication of set alone and not widespread historical practice. The noclobber option was changed to allow set -C as well as the set -o noclobber option. The single-letter version was added so that the historical "$-" paradigm would not be broken; see Section 2.5.2, Special Parameters. The description of the -e option is intended to match the behavior of the 1988 version of the KornShell. The -h flag is related to command name hashing. See hash(1p). The following set flags were omitted intentionally with the following rationale: -k The -k flag was originally added by the author of the Bourne shell to make it easier for users of pre-release versions of the shell. In early versions of the Bourne shell the construct set name=value had to be used to assign values to shell variables. The problem with -k is that the behavior affects parsing, virtually precluding writing any compilers. To explain the behavior of -k, it is necessary to describe the parsing algorithm, which is implementation- defined. For example: set -k; echo name=value and: set -k echo name=value behave differently. The interaction with functions is even more complex. What is more, the -k flag is never needed, since the command line could have been reordered. -t The -t flag is hard to specify and almost never used. The only known use could be done with here-documents. Moreover, the behavior with ksh and sh differs. The reference page says that it exits after reading and executing one command. What is one command? If the input is date;date, sh executes both date commands while ksh does only the first. Consideration was given to rewriting set to simplify its confusing syntax. A specific suggestion was that the unset utility should be used to unset options instead of using the non- getopt()-able +option syntax. However, the conclusion was reached that the historical practice of using +option was satisfactory and that there was no compelling reason to modify such widespread historical practice. The -o option was adopted from the KornShell to address user needs. In addition to its generally friendly interface, -o is needed to provide the vi command line editing mode, for which historical practice yields no single-letter option name. (Although it might have been possible to invent such a letter, it was recognized that other editing modes would be developed and -o provides ample name space for describing such extensions.) Historical implementations are inconsistent in the format used for -o option status reporting. The +o format without an option- argument was added to allow portable access to the options that can be saved and then later restored using, for instance, a dot script. Historically, sh did trace the command set +x, but ksh did not. The ignoreeof setting prevents accidental logouts when the end- of-file character (typically <control>D) is entered. A user shall explicitly exit to leave the interactive shell. The set -m option was added to apply only to the UPE because it applies primarily to interactive use, not shell script applications. The ability to do asynchronous notification became available in the 1988 version of the KornShell. To have it occur, the user had to issue the command: trap "jobs -n" CLD The C shell provides two different levels of an asynchronous notification capability. The environment variable notify is analogous to what is done in set -b or set -o notify. When set, it notifies the user immediately of background job completions. When unset, this capability is turned off. The other notification ability comes through the built-in utility notify. The syntax is: notify [%job ... ] By issuing notify with no operands, it causes the C shell to notify the user asynchronously when the state of the current job changes. If given operands, notify asynchronously informs the user of changes in the states of the specified jobs. To add asynchronous notification to the POSIX shell, neither the KornShell extensions to trap, nor the C shell notify environment variable seemed appropriate (notify is not a proper POSIX environment variable name). The set -b option was selected as a compromise. The notify built-in was considered to have more functionality than was required for simple asynchronous notification. Historically, some shells applied the -u option to all parameters including $@ and $*. The standard developers felt that this was a misfeature since it is normal and common for $@ and $* to be used in shell scripts regardless of whether they were passed any arguments. Treating these uses as an error when no arguments are passed reduces the value of -u for its intended purpose of finding spelling mistakes in variable names and uses of unset positional parameters. FUTURE DIRECTIONS top None. SEE ALSO top Section 2.14, Special Built-In Utilities, hash(1p) The Base Definitions volume of POSIX.12017, Section 4.23, Variable Assignment, Section 12.2, Utility Syntax Guidelines COPYRIGHT top Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html . Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html . IEEE/The Open Group 2017 SET(1P) Pages that refer to this page: pathchk(1p), sh(1p) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. dirname(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training dirname(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | EXAMPLES | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON DIRNAME(1) User Commands DIRNAME(1) NAME top dirname - strip last component from file name SYNOPSIS top dirname [OPTION] NAME... DESCRIPTION top Output each NAME with its last non-slash component and trailing slashes removed; if NAME contains no /'s, output '.' (meaning the current directory). -z, --zero end each output line with NUL, not newline --help display this help and exit --version output version information and exit EXAMPLES top dirname /usr/bin/ -> "/usr" dirname dir1/str dir2/str -> "dir1" followed by "dir2" dirname stdio.h -> "." AUTHOR top Written by David MacKenzie and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top basename(1), readlink(1) Full documentation <https://www.gnu.org/software/coreutils/dirname> or available locally via: info '(coreutils) dirname invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 DIRNAME(1) Pages that refer to this page: basename(1), basename(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates path as current folder path and folder that contains $0 file, and saves result in 'script_dir' variable. Bash Command:<START>set script_dir = `pwd`/`dirname $0`<END>

Creates random file name formatted like expression in variable ${str// /X} and saves it in 'rand_str' variable.

rand_str=$(mktemp --dry-run ${str// /X})

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates random file name formatted like expression in variable ${str// /X} and saves it in 'rand_str' variable. Bash Command:<START>rand_str=$(mktemp --dry-run ${str// /X})<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates random file name formatted like expression in variable ${str// /X} and saves it in 'rand_str' variable. Bash Command:<START>rand_str=$(mktemp --dry-run ${str// /X})<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates random file name formatted like expression in variable ${str// /X} and saves it in 'rand_str' variable. Bash Command:<START>rand_str=$(mktemp --dry-run ${str// /X})<END>

Creates temporary directory in '/tmp/' folder and saves path to it in 'my_tmp_dir' variable.

my_tmp_dir=$(mktemp -d --tmpdir=/tmp)

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary directory in '/tmp/' folder and saves path to it in 'my_tmp_dir' variable. Bash Command:<START>my_tmp_dir=$(mktemp -d --tmpdir=/tmp)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary directory in '/tmp/' folder and saves path to it in 'my_tmp_dir' variable. Bash Command:<START>my_tmp_dir=$(mktemp -d --tmpdir=/tmp)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary directory in '/tmp/' folder and saves path to it in 'my_tmp_dir' variable. Bash Command:<START>my_tmp_dir=$(mktemp -d --tmpdir=/tmp)<END>

Creates temporary directory with name formatted like .daemonXXXXXXX in /tmp/ folder, and saves path to it in 'TMPDIR' variable.

TMPDIR=$(mktemp -p /tmp -d .daemonXXXXXXX)

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary directory with name formatted like .daemonXXXXXXX in /tmp/ folder, and saves path to it in 'TMPDIR' variable. Bash Command:<START>TMPDIR=$(mktemp -p /tmp -d .daemonXXXXXXX)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary directory with name formatted like .daemonXXXXXXX in /tmp/ folder, and saves path to it in 'TMPDIR' variable. Bash Command:<START>TMPDIR=$(mktemp -p /tmp -d .daemonXXXXXXX)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary directory with name formatted like .daemonXXXXXXX in /tmp/ folder, and saves path to it in 'TMPDIR' variable. Bash Command:<START>TMPDIR=$(mktemp -p /tmp -d .daemonXXXXXXX)<END>

Creates temporary file and saves path to it in 'content_dir1' variable.

content_dir1=$(mktemp)

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file and saves path to it in 'content_dir1' variable. Bash Command:<START>content_dir1=$(mktemp)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file and saves path to it in 'content_dir1' variable. Bash Command:<START>content_dir1=$(mktemp)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file and saves path to it in 'content_dir1' variable. Bash Command:<START>content_dir1=$(mktemp)<END>

Creates temporary file and saves path to it in 'content_dir2' variable.

content_dir2=$(mktemp)

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file and saves path to it in 'content_dir2' variable. Bash Command:<START>content_dir2=$(mktemp)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file and saves path to it in 'content_dir2' variable. Bash Command:<START>content_dir2=$(mktemp)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file and saves path to it in 'content_dir2' variable. Bash Command:<START>content_dir2=$(mktemp)<END>

Creates temporary file and saves path to it in 'fif2' variable.

fif2=$(mktemp -u)

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file and saves path to it in 'fif2' variable. Bash Command:<START>fif2=$(mktemp -u)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file and saves path to it in 'fif2' variable. Bash Command:<START>fif2=$(mktemp -u)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file and saves path to it in 'fif2' variable. Bash Command:<START>fif2=$(mktemp -u)<END>

Creates temporary file and saves path to it in a 'tmpfile' variable.

tmpfile=$(mktemp)

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file and saves path to it in a 'tmpfile' variable. Bash Command:<START>tmpfile=$(mktemp)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file and saves path to it in a 'tmpfile' variable. Bash Command:<START>tmpfile=$(mktemp)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file and saves path to it in a 'tmpfile' variable. Bash Command:<START>tmpfile=$(mktemp)<END>

Creates temporary file and saves path to it in a 'tmpfile' variable.

tmpfile=`mktemp`

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file and saves path to it in a 'tmpfile' variable. Bash Command:<START>tmpfile=`mktemp`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file and saves path to it in a 'tmpfile' variable. Bash Command:<START>tmpfile=`mktemp`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file and saves path to it in a 'tmpfile' variable. Bash Command:<START>tmpfile=`mktemp`<END>

Creates temporary file by template provided in option '-t'.

mktemp -t identifier.XXXXXXXXXX

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file by template provided in option '-t'. Bash Command:<START>mktemp -t identifier.XXXXXXXXXX<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file by template provided in option '-t'. Bash Command:<START>mktemp -t identifier.XXXXXXXXXX<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file by template provided in option '-t'. Bash Command:<START>mktemp -t identifier.XXXXXXXXXX<END>

Creates temporary file in $appdir variable with name formatted like expression in variable ${template}, and saves path to it in 'launcherfile' variable.

launcherfile=$(mktemp -p "$appdir" "$template")

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file in $appdir variable with name formatted like expression in variable ${template}, and saves path to it in 'launcherfile' variable. Bash Command:<START>launcherfile=$(mktemp -p "$appdir" "$template")<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file in $appdir variable with name formatted like expression in variable ${template}, and saves path to it in 'launcherfile' variable. Bash Command:<START>launcherfile=$(mktemp -p "$appdir" "$template")<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file in $appdir variable with name formatted like expression in variable ${template}, and saves path to it in 'launcherfile' variable. Bash Command:<START>launcherfile=$(mktemp -p "$appdir" "$template")<END>

Creates temporary file in TMPDIR folder or /tmp/ if TMPDIR is not defined, named by template ${tempname}.XXXXXX, and saves path to new file in a TMPPS_PREFIX variable.

TMPPS_PREFIX=$(mktemp "${TMPDIR:-/tmp/}${tempname}.XXXXXX")

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file in TMPDIR folder or /tmp/ if TMPDIR is not defined, named by template ${tempname}.XXXXXX, and saves path to new file in a TMPPS_PREFIX variable. Bash Command:<START>TMPPS_PREFIX=$(mktemp "${TMPDIR:-/tmp/}${tempname}.XXXXXX")<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file in TMPDIR folder or /tmp/ if TMPDIR is not defined, named by template ${tempname}.XXXXXX, and saves path to new file in a TMPPS_PREFIX variable. Bash Command:<START>TMPPS_PREFIX=$(mktemp "${TMPDIR:-/tmp/}${tempname}.XXXXXX")<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file in TMPDIR folder or /tmp/ if TMPDIR is not defined, named by template ${tempname}.XXXXXX, and saves path to new file in a TMPPS_PREFIX variable. Bash Command:<START>TMPPS_PREFIX=$(mktemp "${TMPDIR:-/tmp/}${tempname}.XXXXXX")<END>

Creates temporary file in a TMPDIR folder or /tmp folder if TMPDIR doesn`t defined, with file name like current shell name and '-XXXXX'-formatted suffix, and saves created path to the 'tempFile' variable.

tempFile="$(mktemp "${TMPDIR:-/tmp/}$(basename "$0")-XXXXX")"

['mktemp', 'basename']

Output a Bash command to accomplish the following task. Task: Creates temporary file in a TMPDIR folder or /tmp folder if TMPDIR doesn`t defined, with file name like current shell name and '-XXXXX'-formatted suffix, and saves created path to the 'tempFile' variable. Bash Command:<START>tempFile="$(mktemp "${TMPDIR:-/tmp/}$(basename "$0")-XXXXX")"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n # basename\n\n> Remove leading directory portions from a path.\n> More information: <https://www.gnu.org/software/coreutils/basename>.\n\n- Show only the file name from a path:\n\n`basename {{path/to/file}}`\n\n- Show only the rightmost directory name from a path:\n\n`basename {{path/to/directory/}}`\n\n- Show only the file name from a path, with a suffix removed:\n\n`basename {{path/to/file}} {{suffix}}`\n Task: Creates temporary file in a TMPDIR folder or /tmp folder if TMPDIR doesn`t defined, with file name like current shell name and '-XXXXX'-formatted suffix, and saves created path to the 'tempFile' variable. Bash Command:<START>tempFile="$(mktemp "${TMPDIR:-/tmp/}$(basename "$0")-XXXXX")"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. basename(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training basename(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | EXAMPLES | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON BASENAME(1) User Commands BASENAME(1) NAME top basename - strip directory and suffix from filenames SYNOPSIS top basename NAME [SUFFIX] basename OPTION... NAME... DESCRIPTION top Print NAME with any leading directory components removed. If specified, also remove a trailing SUFFIX. Mandatory arguments to long options are mandatory for short options too. -a, --multiple support multiple arguments and treat each as a NAME -s, --suffix=SUFFIX remove a trailing SUFFIX; implies -a -z, --zero end each output line with NUL, not newline --help display this help and exit --version output version information and exit EXAMPLES top basename /usr/bin/sort -> "sort" basename include/stdio.h .h -> "stdio" basename -s .h include/stdio.h -> "stdio" basename -a any/str1 any/str2 -> "str1" followed by "str2" AUTHOR top Written by David MacKenzie. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top dirname(1), readlink(1) Full documentation <https://www.gnu.org/software/coreutils/basename> or available locally via: info '(coreutils) basename invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 BASENAME(1) Pages that refer to this page: dirname(1), pmsignal(1), basename(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file in a TMPDIR folder or /tmp folder if TMPDIR doesn`t defined, with file name like current shell name and '-XXXXX'-formatted suffix, and saves created path to the 'tempFile' variable. Bash Command:<START>tempFile="$(mktemp "${TMPDIR:-/tmp/}$(basename "$0")-XXXXX")"<END>

Creates temporary file in a TMPDIR folder with name like tmp.XXXXXXXXXX.

mktemp

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file in a TMPDIR folder with name like tmp.XXXXXXXXXX. Bash Command:<START>mktemp<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file in a TMPDIR folder with name like tmp.XXXXXXXXXX. Bash Command:<START>mktemp<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file in a TMPDIR folder with name like tmp.XXXXXXXXXX. Bash Command:<START>mktemp<END>

Creates temporary file in a current folder and saves path to it in 'f' variable.

f=`mktemp -p .`

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file in a current folder and saves path to it in 'f' variable. Bash Command:<START>f=`mktemp -p .`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file in a current folder and saves path to it in 'f' variable. Bash Command:<START>f=`mktemp -p .`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file in a current folder and saves path to it in 'f' variable. Bash Command:<START>f=`mktemp -p .`<END>

Creates temporary file in a current folder with name formatted like 'templateXXXXXX', and saves path to it in 'tempfile' variable.

tempfile=$(mktemp $(pwd)/templateXXXXXX)

['pwd', 'mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file in a current folder with name formatted like 'templateXXXXXX', and saves path to it in 'tempfile' variable. Bash Command:<START>tempfile=$(mktemp $(pwd)/templateXXXXXX)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # pwd\n\n> Print name of current/working directory.\n> More information: <https://www.gnu.org/software/coreutils/pwd>.\n\n- Print the current directory:\n\n`pwd`\n\n- Print the current directory, and resolve all symlinks (i.e. show the "physical" path):\n\n`pwd --physical`\n\n- Print the current logical directory:\n\n`pwd --logical`\n # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file in a current folder with name formatted like 'templateXXXXXX', and saves path to it in 'tempfile' variable. Bash Command:<START>tempfile=$(mktemp $(pwd)/templateXXXXXX)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: pwd(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training pwd(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON PWD(1) User Commands PWD(1) NAME top pwd - print name of current/working directory SYNOPSIS top pwd [OPTION]... DESCRIPTION top Print the full filename of the current working directory. -L, --logical use PWD from environment, even if it contains symlinks -P, --physical avoid all symlinks --help display this help and exit --version output version information and exit If no option is specified, -P is assumed. NOTE: your shell may have its own version of pwd, which usually supersedes the version described here. Please refer to your shell's documentation for details about the options it supports. AUTHOR top Written by Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top getcwd(3) Full documentation <https://www.gnu.org/software/coreutils/pwd> or available locally via: info '(coreutils) pwd invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 PWD(1) Pages that refer to this page: getcwd(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file in a current folder with name formatted like 'templateXXXXXX', and saves path to it in 'tempfile' variable. Bash Command:<START>tempfile=$(mktemp $(pwd)/templateXXXXXX)<END>

Creates temporary file in default folder and saves path to it in 'source' variable.

source=`mktemp`

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file in default folder and saves path to it in 'source' variable. Bash Command:<START>source=`mktemp`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file in default folder and saves path to it in 'source' variable. Bash Command:<START>source=`mktemp`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file in default folder and saves path to it in 'source' variable. Bash Command:<START>source=`mktemp`<END>

Creates temporary file name and saves path to it in 'TMP_FILE' variable.

TMP_FILE="$(mktemp -t)"

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file name and saves path to it in 'TMP_FILE' variable. Bash Command:<START>TMP_FILE="$(mktemp -t)"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file name and saves path to it in 'TMP_FILE' variable. Bash Command:<START>TMP_FILE="$(mktemp -t)"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file name and saves path to it in 'TMP_FILE' variable. Bash Command:<START>TMP_FILE="$(mktemp -t)"<END>

Creates temporary file with appended suffix '.cmd' and saves path to it in 'LGT_TEMP_FILE' variable.

LGT_TEMP_FILE="$(mktemp --suffix .cmd)"

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file with appended suffix '.cmd' and saves path to it in 'LGT_TEMP_FILE' variable. Bash Command:<START>LGT_TEMP_FILE="$(mktemp --suffix .cmd)"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file with appended suffix '.cmd' and saves path to it in 'LGT_TEMP_FILE' variable. Bash Command:<START>LGT_TEMP_FILE="$(mktemp --suffix .cmd)"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file with appended suffix '.cmd' and saves path to it in 'LGT_TEMP_FILE' variable. Bash Command:<START>LGT_TEMP_FILE="$(mktemp --suffix .cmd)"<END>

Creates temporary file with file name formatted like /tmp/gnuplot_cmd_$(basename "${0}").XXXXXX.gnuplot and saves path to it in a variable 'gnuplotscript'.

gnuplotscript=$(mktemp /tmp/gnuplot_cmd_$(basename "${0}").XXXXXX.gnuplot)

['mktemp', 'basename']

Output a Bash command to accomplish the following task. Task: Creates temporary file with file name formatted like /tmp/gnuplot_cmd_$(basename "${0}").XXXXXX.gnuplot and saves path to it in a variable 'gnuplotscript'. Bash Command:<START>gnuplotscript=$(mktemp /tmp/gnuplot_cmd_$(basename "${0}").XXXXXX.gnuplot)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n # basename\n\n> Remove leading directory portions from a path.\n> More information: <https://www.gnu.org/software/coreutils/basename>.\n\n- Show only the file name from a path:\n\n`basename {{path/to/file}}`\n\n- Show only the rightmost directory name from a path:\n\n`basename {{path/to/directory/}}`\n\n- Show only the file name from a path, with a suffix removed:\n\n`basename {{path/to/file}} {{suffix}}`\n Task: Creates temporary file with file name formatted like /tmp/gnuplot_cmd_$(basename "${0}").XXXXXX.gnuplot and saves path to it in a variable 'gnuplotscript'. Bash Command:<START>gnuplotscript=$(mktemp /tmp/gnuplot_cmd_$(basename "${0}").XXXXXX.gnuplot)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. basename(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training basename(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | EXAMPLES | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON BASENAME(1) User Commands BASENAME(1) NAME top basename - strip directory and suffix from filenames SYNOPSIS top basename NAME [SUFFIX] basename OPTION... NAME... DESCRIPTION top Print NAME with any leading directory components removed. If specified, also remove a trailing SUFFIX. Mandatory arguments to long options are mandatory for short options too. -a, --multiple support multiple arguments and treat each as a NAME -s, --suffix=SUFFIX remove a trailing SUFFIX; implies -a -z, --zero end each output line with NUL, not newline --help display this help and exit --version output version information and exit EXAMPLES top basename /usr/bin/sort -> "sort" basename include/stdio.h .h -> "stdio" basename -s .h include/stdio.h -> "stdio" basename -a any/str1 any/str2 -> "str1" followed by "str2" AUTHOR top Written by David MacKenzie. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top dirname(1), readlink(1) Full documentation <https://www.gnu.org/software/coreutils/basename> or available locally via: info '(coreutils) basename invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 BASENAME(1) Pages that refer to this page: dirname(1), pmsignal(1), basename(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file with file name formatted like /tmp/gnuplot_cmd_$(basename "${0}").XXXXXX.gnuplot and saves path to it in a variable 'gnuplotscript'. Bash Command:<START>gnuplotscript=$(mktemp /tmp/gnuplot_cmd_$(basename "${0}").XXXXXX.gnuplot)<END>

Creates temporary file with name formatted like '.script.XXXXXX' in '/tmp/' folder and saves path to it in 'script1' variable.

script1=`mktemp /tmp/.script.XXXXXX`;

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file with name formatted like '.script.XXXXXX' in '/tmp/' folder and saves path to it in 'script1' variable. Bash Command:<START>script1=`mktemp /tmp/.script.XXXXXX`;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file with name formatted like '.script.XXXXXX' in '/tmp/' folder and saves path to it in 'script1' variable. Bash Command:<START>script1=`mktemp /tmp/.script.XXXXXX`;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file with name formatted like '.script.XXXXXX' in '/tmp/' folder and saves path to it in 'script1' variable. Bash Command:<START>script1=`mktemp /tmp/.script.XXXXXX`;<END>

Creates temporary file with name formatted like '.script.XXXXXX' in '/tmp/' folder and saves path to it in 'script2' variable.

script2=`mktemp /tmp/.script.XXXXXX`;

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file with name formatted like '.script.XXXXXX' in '/tmp/' folder and saves path to it in 'script2' variable. Bash Command:<START>script2=`mktemp /tmp/.script.XXXXXX`;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file with name formatted like '.script.XXXXXX' in '/tmp/' folder and saves path to it in 'script2' variable. Bash Command:<START>script2=`mktemp /tmp/.script.XXXXXX`;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file with name formatted like '.script.XXXXXX' in '/tmp/' folder and saves path to it in 'script2' variable. Bash Command:<START>script2=`mktemp /tmp/.script.XXXXXX`;<END>

Creates temporary file with name formatted like 'emacs-manager.XXXXXX' in '/tmp/' folder and saves path to it in 'tmp_file' variable.

tmp_file=`mktemp --tmpdir=/tmp emacs-manager.XXXXXX`

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file with name formatted like 'emacs-manager.XXXXXX' in '/tmp/' folder and saves path to it in 'tmp_file' variable. Bash Command:<START>tmp_file=`mktemp --tmpdir=/tmp emacs-manager.XXXXXX`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file with name formatted like 'emacs-manager.XXXXXX' in '/tmp/' folder and saves path to it in 'tmp_file' variable. Bash Command:<START>tmp_file=`mktemp --tmpdir=/tmp emacs-manager.XXXXXX`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file with name formatted like 'emacs-manager.XXXXXX' in '/tmp/' folder and saves path to it in 'tmp_file' variable. Bash Command:<START>tmp_file=`mktemp --tmpdir=/tmp emacs-manager.XXXXXX`<END>

Creates temporary file with name formatted like expression in variable ${PROG}, and saves path to it in 'mytemp' variable.

mytemp="$(mktemp -t "${PROG}")"

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file with name formatted like expression in variable ${PROG}, and saves path to it in 'mytemp' variable. Bash Command:<START>mytemp="$(mktemp -t "${PROG}")"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file with name formatted like expression in variable ${PROG}, and saves path to it in 'mytemp' variable. Bash Command:<START>mytemp="$(mktemp -t "${PROG}")"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file with name formatted like expression in variable ${PROG}, and saves path to it in 'mytemp' variable. Bash Command:<START>mytemp="$(mktemp -t "${PROG}")"<END>

Creates temporary file, replacing XXXXXXXXXXXXXXXXXXXXXXX with equal length suffix.

mktemp /tmp/banana.XXXXXXXXXXXXXXXXXXXXXXX.mp3

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary file, replacing XXXXXXXXXXXXXXXXXXXXXXX with equal length suffix. Bash Command:<START>mktemp /tmp/banana.XXXXXXXXXXXXXXXXXXXXXXX.mp3<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary file, replacing XXXXXXXXXXXXXXXXXXXXXXX with equal length suffix. Bash Command:<START>mktemp /tmp/banana.XXXXXXXXXXXXXXXXXXXXXXX.mp3<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary file, replacing XXXXXXXXXXXXXXXXXXXXXXX with equal length suffix. Bash Command:<START>mktemp /tmp/banana.XXXXXXXXXXXXXXXXXXXXXXX.mp3<END>

Creates temporary folder and save path to that in a TMPDIR variable.

TMPDIR=$(mktemp -d)

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary folder and save path to that in a TMPDIR variable. Bash Command:<START>TMPDIR=$(mktemp -d)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary folder and save path to that in a TMPDIR variable. Bash Command:<START>TMPDIR=$(mktemp -d)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary folder and save path to that in a TMPDIR variable. Bash Command:<START>TMPDIR=$(mktemp -d)<END>

Creates temporary folder and saves path to it in 'other' variable.

other="$(mktemp --directory)"

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary folder and saves path to it in 'other' variable. Bash Command:<START>other="$(mktemp --directory)"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary folder and saves path to it in 'other' variable. Bash Command:<START>other="$(mktemp --directory)"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary folder and saves path to it in 'other' variable. Bash Command:<START>other="$(mktemp --directory)"<END>

Creates temporary folder and saves path to it in 'td' variable.

td=$( mktemp -d )

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary folder and saves path to it in 'td' variable. Bash Command:<START>td=$( mktemp -d )<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary folder and saves path to it in 'td' variable. Bash Command:<START>td=$( mktemp -d )<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary folder and saves path to it in 'td' variable. Bash Command:<START>td=$( mktemp -d )<END>

Creates temporary folder and saves path to it in a 'tempd' variable.

tempd=`mktemp -d`

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary folder and saves path to it in a 'tempd' variable. Bash Command:<START>tempd=`mktemp -d`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary folder and saves path to it in a 'tempd' variable. Bash Command:<START>tempd=`mktemp -d`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary folder and saves path to it in a 'tempd' variable. Bash Command:<START>tempd=`mktemp -d`<END>

Creates temporary folder in /tmp/ (by default) with 10-letter suffux.

mktemp -d -t

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary folder in /tmp/ (by default) with 10-letter suffux. Bash Command:<START>mktemp -d -t<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary folder in /tmp/ (by default) with 10-letter suffux. Bash Command:<START>mktemp -d -t<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary folder in /tmp/ (by default) with 10-letter suffux. Bash Command:<START>mktemp -d -t<END>

Creates temporary folder in TMPDIR (if defined) or in '/tmp/', and stores path to created folder in 'dir' variable.

dir=$(mktemp -d)

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary folder in TMPDIR (if defined) or in '/tmp/', and stores path to created folder in 'dir' variable. Bash Command:<START>dir=$(mktemp -d)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary folder in TMPDIR (if defined) or in '/tmp/', and stores path to created folder in 'dir' variable. Bash Command:<START>dir=$(mktemp -d)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary folder in TMPDIR (if defined) or in '/tmp/', and stores path to created folder in 'dir' variable. Bash Command:<START>dir=$(mktemp -d)<END>

Creates temporary folder in TMPDIR (if defined) or in '/tmp/', and stores path to created folder in 'tmpdir' variable.

tmpdir=$(mktemp -d)

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary folder in TMPDIR (if defined) or in '/tmp/', and stores path to created folder in 'tmpdir' variable. Bash Command:<START>tmpdir=$(mktemp -d)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary folder in TMPDIR (if defined) or in '/tmp/', and stores path to created folder in 'tmpdir' variable. Bash Command:<START>tmpdir=$(mktemp -d)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary folder in TMPDIR (if defined) or in '/tmp/', and stores path to created folder in 'tmpdir' variable. Bash Command:<START>tmpdir=$(mktemp -d)<END>

Creates temporary folder in a $temp_dir folder with name pattern defined by $template, and stores path to created folder in 'my_temp' variable.

$ my_temp_dir=$(mktemp -d --tmpdir=$temp_dir -t $template)

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary folder in a $temp_dir folder with name pattern defined by $template, and stores path to created folder in 'my_temp' variable. Bash Command:<START>$ my_temp_dir=$(mktemp -d --tmpdir=$temp_dir -t $template)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary folder in a $temp_dir folder with name pattern defined by $template, and stores path to created folder in 'my_temp' variable. Bash Command:<START>$ my_temp_dir=$(mktemp -d --tmpdir=$temp_dir -t $template)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary folder in a $temp_dir folder with name pattern defined by $template, and stores path to created folder in 'my_temp' variable. Bash Command:<START>$ my_temp_dir=$(mktemp -d --tmpdir=$temp_dir -t $template)<END>

Creates temporary folder in a TMPDIR folder or /tmp folder if TMPDIR doesn`t defined, with folder name like current shell name and 10-letter suffix, and saves created path in 'mydir' variable.

mydir=$(mktemp -d "${TMPDIR:-/tmp/}$(basename $0).XXXXXXXXXXXX")

['mktemp', 'basename']

Output a Bash command to accomplish the following task. Task: Creates temporary folder in a TMPDIR folder or /tmp folder if TMPDIR doesn`t defined, with folder name like current shell name and 10-letter suffix, and saves created path in 'mydir' variable. Bash Command:<START>mydir=$(mktemp -d "${TMPDIR:-/tmp/}$(basename $0).XXXXXXXXXXXX")<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n # basename\n\n> Remove leading directory portions from a path.\n> More information: <https://www.gnu.org/software/coreutils/basename>.\n\n- Show only the file name from a path:\n\n`basename {{path/to/file}}`\n\n- Show only the rightmost directory name from a path:\n\n`basename {{path/to/directory/}}`\n\n- Show only the file name from a path, with a suffix removed:\n\n`basename {{path/to/file}} {{suffix}}`\n Task: Creates temporary folder in a TMPDIR folder or /tmp folder if TMPDIR doesn`t defined, with folder name like current shell name and 10-letter suffix, and saves created path in 'mydir' variable. Bash Command:<START>mydir=$(mktemp -d "${TMPDIR:-/tmp/}$(basename $0).XXXXXXXXXXXX")<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. basename(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training basename(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | EXAMPLES | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON BASENAME(1) User Commands BASENAME(1) NAME top basename - strip directory and suffix from filenames SYNOPSIS top basename NAME [SUFFIX] basename OPTION... NAME... DESCRIPTION top Print NAME with any leading directory components removed. If specified, also remove a trailing SUFFIX. Mandatory arguments to long options are mandatory for short options too. -a, --multiple support multiple arguments and treat each as a NAME -s, --suffix=SUFFIX remove a trailing SUFFIX; implies -a -z, --zero end each output line with NUL, not newline --help display this help and exit --version output version information and exit EXAMPLES top basename /usr/bin/sort -> "sort" basename include/stdio.h .h -> "stdio" basename -s .h include/stdio.h -> "stdio" basename -a any/str1 any/str2 -> "str1" followed by "str2" AUTHOR top Written by David MacKenzie. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top dirname(1), readlink(1) Full documentation <https://www.gnu.org/software/coreutils/basename> or available locally via: info '(coreutils) basename invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 BASENAME(1) Pages that refer to this page: dirname(1), pmsignal(1), basename(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary folder in a TMPDIR folder or /tmp folder if TMPDIR doesn`t defined, with folder name like current shell name and 10-letter suffix, and saves created path in 'mydir' variable. Bash Command:<START>mydir=$(mktemp -d "${TMPDIR:-/tmp/}$(basename $0).XXXXXXXXXXXX")<END>

Creates temporary folder like '/tmp/tardir-XXXXXX' with 6-letter suffix and saves its path in 'tmpdir' variable.

tmpdir=$(mktemp -d /tmp/tardir-XXXXXX)

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary folder like '/tmp/tardir-XXXXXX' with 6-letter suffix and saves its path in 'tmpdir' variable. Bash Command:<START>tmpdir=$(mktemp -d /tmp/tardir-XXXXXX)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary folder like '/tmp/tardir-XXXXXX' with 6-letter suffix and saves its path in 'tmpdir' variable. Bash Command:<START>tmpdir=$(mktemp -d /tmp/tardir-XXXXXX)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary folder like '/tmp/tardir-XXXXXX' with 6-letter suffix and saves its path in 'tmpdir' variable. Bash Command:<START>tmpdir=$(mktemp -d /tmp/tardir-XXXXXX)<END>

Creates temporary folder relative to directory '/path/to/dir'.

mktemp -d -p /path/to/dir

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary folder relative to directory '/path/to/dir'. Bash Command:<START>mktemp -d -p /path/to/dir<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary folder relative to directory '/path/to/dir'. Bash Command:<START>mktemp -d -p /path/to/dir<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary folder relative to directory '/path/to/dir'. Bash Command:<START>mktemp -d -p /path/to/dir<END>

Creates temporary folder within TMPDIR, with name like current shell name and 10-letter suffix.

mktemp -dt "$(basename $0).XXXXXXXXXX"

['mktemp', 'basename']

Output a Bash command to accomplish the following task. Task: Creates temporary folder within TMPDIR, with name like current shell name and 10-letter suffix. Bash Command:<START>mktemp -dt "$(basename $0).XXXXXXXXXX"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n # basename\n\n> Remove leading directory portions from a path.\n> More information: <https://www.gnu.org/software/coreutils/basename>.\n\n- Show only the file name from a path:\n\n`basename {{path/to/file}}`\n\n- Show only the rightmost directory name from a path:\n\n`basename {{path/to/directory/}}`\n\n- Show only the file name from a path, with a suffix removed:\n\n`basename {{path/to/file}} {{suffix}}`\n Task: Creates temporary folder within TMPDIR, with name like current shell name and 10-letter suffix. Bash Command:<START>mktemp -dt "$(basename $0).XXXXXXXXXX"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. basename(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training basename(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | EXAMPLES | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON BASENAME(1) User Commands BASENAME(1) NAME top basename - strip directory and suffix from filenames SYNOPSIS top basename NAME [SUFFIX] basename OPTION... NAME... DESCRIPTION top Print NAME with any leading directory components removed. If specified, also remove a trailing SUFFIX. Mandatory arguments to long options are mandatory for short options too. -a, --multiple support multiple arguments and treat each as a NAME -s, --suffix=SUFFIX remove a trailing SUFFIX; implies -a -z, --zero end each output line with NUL, not newline --help display this help and exit --version output version information and exit EXAMPLES top basename /usr/bin/sort -> "sort" basename include/stdio.h .h -> "stdio" basename -s .h include/stdio.h -> "stdio" basename -a any/str1 any/str2 -> "str1" followed by "str2" AUTHOR top Written by David MacKenzie. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top dirname(1), readlink(1) Full documentation <https://www.gnu.org/software/coreutils/basename> or available locally via: info '(coreutils) basename invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 BASENAME(1) Pages that refer to this page: dirname(1), pmsignal(1), basename(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary folder within TMPDIR, with name like current shell name and 10-letter suffix. Bash Command:<START>mktemp -dt "$(basename $0).XXXXXXXXXX"<END>

Creates temporary folder within a $mnt_dir folder and saves path to it in a 'rsync_src' variable.

rsync_src=`mktemp -d -p $mnt_dir`

['mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary folder within a $mnt_dir folder and saves path to it in a 'rsync_src' variable. Bash Command:<START>rsync_src=`mktemp -d -p $mnt_dir`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary folder within a $mnt_dir folder and saves path to it in a 'rsync_src' variable. Bash Command:<START>rsync_src=`mktemp -d -p $mnt_dir`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary folder within a $mnt_dir folder and saves path to it in a 'rsync_src' variable. Bash Command:<START>rsync_src=`mktemp -d -p $mnt_dir`<END>

Creates temporary folder, and saves current folder path joined with created temporary folder path in 'tdir' variable.

tdir="$(pwd)/$(mktemp -d)"

['pwd', 'mktemp']

Output a Bash command to accomplish the following task. Task: Creates temporary folder, and saves current folder path joined with created temporary folder path in 'tdir' variable. Bash Command:<START>tdir="$(pwd)/$(mktemp -d)"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # pwd\n\n> Print name of current/working directory.\n> More information: <https://www.gnu.org/software/coreutils/pwd>.\n\n- Print the current directory:\n\n`pwd`\n\n- Print the current directory, and resolve all symlinks (i.e. show the "physical" path):\n\n`pwd --physical`\n\n- Print the current logical directory:\n\n`pwd --logical`\n # mktemp\n\n> Create a temporary file or directory.\n> More information: <https://www.gnu.org/software/coreutils/mktemp>.\n\n- Create an empty temporary file and print its absolute path:\n\n`mktemp`\n\n- Use a custom directory (defaults to `$TMPDIR`, or `/tmp`):\n\n`mktemp --tmpdir={{/path/to/tempdir}}`\n\n- Use a custom path template (`X`s are replaced with random alphanumeric characters):\n\n`mktemp {{/tmp/example.XXXXXXXX}}`\n\n- Use a custom file name template:\n\n`mktemp -t {{example.XXXXXXXX}}`\n\n- Create an empty temporary file with the given suffix and print its absolute path:\n\n`mktemp --suffix {{.ext}}`\n\n- Create an empty temporary directory and print its absolute path:\n\n`mktemp --directory`\n Task: Creates temporary folder, and saves current folder path joined with created temporary folder path in 'tdir' variable. Bash Command:<START>tdir="$(pwd)/$(mktemp -d)"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: pwd(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training pwd(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON PWD(1) User Commands PWD(1) NAME top pwd - print name of current/working directory SYNOPSIS top pwd [OPTION]... DESCRIPTION top Print the full filename of the current working directory. -L, --logical use PWD from environment, even if it contains symlinks -P, --physical avoid all symlinks --help display this help and exit --version output version information and exit If no option is specified, -P is assumed. NOTE: your shell may have its own version of pwd, which usually supersedes the version described here. Please refer to your shell's documentation for details about the options it supports. AUTHOR top Written by Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top getcwd(3) Full documentation <https://www.gnu.org/software/coreutils/pwd> or available locally via: info '(coreutils) pwd invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 PWD(1) Pages that refer to this page: getcwd(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. mktemp(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training mktemp(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON MKTEMP(1) User Commands MKTEMP(1) NAME top mktemp - create a temporary file or directory SYNOPSIS top mktemp [OPTION]... [TEMPLATE] DESCRIPTION top Create a temporary file or directory, safely, and print its name. TEMPLATE must contain at least 3 consecutive 'X's in last component. If TEMPLATE is not specified, use tmp.XXXXXXXXXX, and --tmpdir is implied. Files are created u+rw, and directories u+rwx, minus umask restrictions. -d, --directory create a directory, not a file -u, --dry-run do not create anything; merely print a name (unsafe) -q, --quiet suppress diagnostics about file/dir-creation failure --suffix=SUFF append SUFF to TEMPLATE; SUFF must not contain a slash. This option is implied if TEMPLATE does not end in X -p DIR, --tmpdir[=DIR] interpret TEMPLATE relative to DIR; if DIR is not specified, use $TMPDIR if set, else /tmp. With this option, TEMPLATE must not be an absolute name; unlike with -t, TEMPLATE may contain slashes, but mktemp creates only the final component -t interpret TEMPLATE as a single file name component, relative to a directory: $TMPDIR, if set; else the directory specified via -p; else /tmp [deprecated] --help display this help and exit --version output version information and exit AUTHOR top Written by Jim Meyering and Eric Blake. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top mkstemp(3), mkdtemp(3), mktemp(3) Full documentation <https://www.gnu.org/software/coreutils/mktemp> or available locally via: info '(coreutils) mktemp invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 MKTEMP(1) Pages that refer to this page: mkdtemp(3), mktemp(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Creates temporary folder, and saves current folder path joined with created temporary folder path in 'tdir' variable. Bash Command:<START>tdir="$(pwd)/$(mktemp -d)"<END>

Cut all remote paths from HTTP URLs received from standard input (one per line) keeping only the protocol identifier and host name, of the form http://example.com

sed -n 's;\(http://[^/]*\)/.*;\1;p'

['sed']

Output a Bash command to accomplish the following task. Task: Cut all remote paths from HTTP URLs received from standard input (one per line) keeping only the protocol identifier and host name, of the form http://example.com Bash Command:<START>sed -n 's;\(http://[^/]*\)/.*;\1;p'<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # sed\n\n> Edit text in a scriptable manner.\n> See also: `awk`, `ed`.\n> More information: <https://www.gnu.org/software/sed/manual/sed.html>.\n\n- Replace all `apple` (basic regex) occurrences with `mango` (basic regex) in all input lines and print the result to `stdout`:\n\n`{{command}} | sed 's/apple/mango/g'`\n\n- Replace all `apple` (extended regex) occurrences with `APPLE` (extended regex) in all input lines and print the result to `stdout`:\n\n`{{command}} | sed -E 's/(apple)/\U\1/g'`\n\n- Replace all `apple` (basic regex) occurrences with `mango` (basic regex) in a specific file and overwrite the original file in place:\n\n`sed -i 's/apple/mango/g' {{path/to/file}}`\n\n- Execute a specific script [f]ile and print the result to `stdout`:\n\n`{{command}} | sed -f {{path/to/script.sed}}`\n\n- Print just the first line to `stdout`:\n\n`{{command}} | sed -n '1p'`\n\n- [d]elete the first line of a file:\n\n`sed -i 1d {{path/to/file}}`\n\n- [i]nsert a new line at the first line of a file:\n\n`sed -i '1i\your new line text\' {{path/to/file}}`\n Task: Cut all remote paths from HTTP URLs received from standard input (one per line) keeping only the protocol identifier and host name, of the form http://example.com Bash Command:<START>sed -n 's;\(http://[^/]*\)/.*;\1;p'<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: sed(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training sed(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | COMMAND SYNOPSIS | REGULAR EXPRESSIONS | BUGS | AUTHOR | COPYRIGHT | SEE ALSO | COLOPHON SED(1) User Commands SED(1) NAME top sed - stream editor for filtering and transforming text SYNOPSIS top sed [-V] [--version] [--help] [-n] [--quiet] [--silent] [-l N] [--line-length=N] [-u] [--unbuffered] [-E] [-r] [--regexp-extended] [-e script] [--expression=script] [-f script-file] [--file=script-file] [script-if-no-other-script] [file...] DESCRIPTION top Sed is a stream editor. A stream editor is used to perform basic text transformations on an input stream (a file or input from a pipeline). While in some ways similar to an editor which permits scripted edits (such as ed), sed works by making only one pass over the input(s), and is consequently more efficient. But it is sed's ability to filter text in a pipeline which particularly distinguishes it from other types of editors. -n, --quiet, --silent suppress automatic printing of pattern space --debug annotate program execution -e script, --expression=script add the script to the commands to be executed -f script-file, --file=script-file add the contents of script-file to the commands to be executed --follow-symlinks follow symlinks when processing in place -i[SUFFIX], --in-place[=SUFFIX] edit files in place (makes backup if SUFFIX supplied) -l N, --line-length=N specify the desired line-wrap length for the `l' command --posix disable all GNU extensions. -E, -r, --regexp-extended use extended regular expressions in the script (for portability use POSIX -E). -s, --separate consider files as separate rather than as a single, continuous long stream. --sandbox operate in sandbox mode (disable e/r/w commands). -u, --unbuffered load minimal amounts of data from the input files and flush the output buffers more often -z, --null-data separate lines by NUL characters --help display this help and exit --version output version information and exit If no -e, --expression, -f, or --file option is given, then the first non-option argument is taken as the sed script to interpret. All remaining arguments are names of input files; if no input files are specified, then the standard input is read. GNU sed home page: <https://www.gnu.org/software/sed/>. General help using GNU software: <https://www.gnu.org/gethelp/>. E-mail bug reports to: <bug-sed@gnu.org>. COMMAND SYNOPSIS top This is just a brief synopsis of sed commands to serve as a reminder to those who already know sed; other documentation (such as the texinfo document) must be consulted for fuller descriptions. Zero-address ``commands'' : label Label for b and t commands. #comment The comment extends until the next newline (or the end of a -e script fragment). } The closing bracket of a { } block. Zero- or One- address commands = Print the current line number. a \ text Append text, which has each embedded newline preceded by a backslash. i \ text Insert text, which has each embedded newline preceded by a backslash. q [exit-code] Immediately quit the sed script without processing any more input, except that if auto-print is not disabled the current pattern space will be printed. The exit code argument is a GNU extension. Q [exit-code] Immediately quit the sed script without processing any more input. This is a GNU extension. r filename Append text read from filename. R filename Append a line read from filename. Each invocation of the command reads a line from the file. This is a GNU extension. Commands which accept address ranges { Begin a block of commands (end with a }). b label Branch to label; if label is omitted, branch to end of script. c \ text Replace the selected lines with text, which has each embedded newline preceded by a backslash. d Delete pattern space. Start next cycle. D If pattern space contains no newline, start a normal new cycle as if the d command was issued. Otherwise, delete text in the pattern space up to the first newline, and restart cycle with the resultant pattern space, without reading a new line of input. h H Copy/append pattern space to hold space. g G Copy/append hold space to pattern space. l List out the current line in a ``visually unambiguous'' form. l width List out the current line in a ``visually unambiguous'' form, breaking it at width characters. This is a GNU extension. n N Read/append the next line of input into the pattern space. p Print the current pattern space. P Print up to the first embedded newline of the current pattern space. s/regexp/replacement/ Attempt to match regexp against the pattern space. If successful, replace that portion matched with replacement. The replacement may contain the special character & to refer to that portion of the pattern space which matched, and the special escapes \1 through \9 to refer to the corresponding matching sub-expressions in the regexp. t label If a s/// has done a successful substitution since the last input line was read and since the last t or T command, then branch to label; if label is omitted, branch to end of script. T label If no s/// has done a successful substitution since the last input line was read and since the last t or T command, then branch to label; if label is omitted, branch to end of script. This is a GNU extension. w filename Write the current pattern space to filename. W filename Write the first line of the current pattern space to filename. This is a GNU extension. x Exchange the contents of the hold and pattern spaces. y/source/dest/ Transliterate the characters in the pattern space which appear in source to the corresponding character in dest. Addresses Sed commands can be given with no addresses, in which case the command will be executed for all input lines; with one address, in which case the command will only be executed for input lines which match that address; or with two addresses, in which case the command will be executed for all input lines which match the inclusive range of lines starting from the first address and continuing to the second address. Three things to note about address ranges: the syntax is addr1,addr2 (i.e., the addresses are separated by a comma); the line which addr1 matched will always be accepted, even if addr2 selects an earlier line; and if addr2 is a regexp, it will not be tested against the line that addr1 matched. After the address (or address-range), and before the command, a ! may be inserted, which specifies that the command shall only be executed if the address (or address-range) does not match. The following address types are supported: number Match only the specified line number (which increments cumulatively across files, unless the -s option is specified on the command line). first~step Match every step'th line starting with line first. For example, ``sed -n 1~2p'' will print all the odd-numbered lines in the input stream, and the address 2~5 will match every fifth line, starting with the second. first can be zero; in this case, sed operates as if it were equal to step. (This is an extension.) $ Match the last line. /regexp/ Match lines matching the regular expression regexp. Matching is performed on the current pattern space, which can be modified with commands such as ``s///''. \cregexpc Match lines matching the regular expression regexp. The c may be any character. GNU sed also supports some special 2-address forms: 0,addr2 Start out in "matched first address" state, until addr2 is found. This is similar to 1,addr2, except that if addr2 matches the very first line of input the 0,addr2 form will be at the end of its range, whereas the 1,addr2 form will still be at the beginning of its range. This works only when addr2 is a regular expression. addr1,+N Will match addr1 and the N lines following addr1. addr1,~N Will match addr1 and the lines following addr1 until the next line whose input line number is a multiple of N. REGULAR EXPRESSIONS top POSIX.2 BREs should be supported, but they aren't completely because of performance problems. The \n sequence in a regular expression matches the newline character, and similarly for \a, \t, and other sequences. The -E option switches to using extended regular expressions instead; it has been supported for years by GNU sed, and is now included in POSIX. BUGS top E-mail bug reports to bug-sed@gnu.org. Also, please include the output of ``sed --version'' in the body of your report if at all possible. AUTHOR top Written by Jay Fenlason, Tom Lord, Ken Pizzini, Paolo Bonzini, Jim Meyering, and Assaf Gordon. This sed program was built with SELinux support. SELinux is enabled on this system. GNU sed home page: <https://www.gnu.org/software/sed/>. General help using GNU software: <https://www.gnu.org/gethelp/>. E-mail bug reports to: <bug-sed@gnu.org>. COPYRIGHT top Copyright 2022 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top awk(1), ed(1), grep(1), tr(1), perlre(1), sed.info, any of various books on sed, the sed FAQ (http://sed.sf.net/grabbag/tutorials/sedfaq.txt), http://sed.sf.net/grabbag/. The full documentation for sed is maintained as a Texinfo manual. If the info and sed programs are properly installed at your site, the command info sed should give you access to the complete manual. COLOPHON top This page is part of the sed (stream-oriented editor) project. Information about the project can be found at http://www.gnu.org/software/sed/. If you have a bug report for this manual page, send it to bug-sed@gnu.org. This page was obtained from the tarball sed-4.9.tar.gz fetched from https://www.gnu.org/software/sed/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU sed 4.9 November 2022 SED(1) Pages that refer to this page: gawk(1), grep(1), iostat2pcp(1), pmdaopenmetrics(1), pmlogrewrite(1), sheet2pcp(1), cpuset(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Cut all remote paths from HTTP URLs received from standard input (one per line) keeping only the protocol identifier and host name, of the form http://example.com Bash Command:<START>sed -n 's;\(http://[^/]*\)/.*;\1;p'<END>

Cut all remote paths from HTTP URLs received from standard input (one per line) keeping only the protocol identifier, host name, and trailing slash, of the form http://example.com/

sed -n 's;\(http://[^/]*/\).*;\1;p'

['sed']

Output a Bash command to accomplish the following task. Task: Cut all remote paths from HTTP URLs received from standard input (one per line) keeping only the protocol identifier, host name, and trailing slash, of the form http://example.com/ Bash Command:<START>sed -n 's;\(http://[^/]*/\).*;\1;p'<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # sed\n\n> Edit text in a scriptable manner.\n> See also: `awk`, `ed`.\n> More information: <https://www.gnu.org/software/sed/manual/sed.html>.\n\n- Replace all `apple` (basic regex) occurrences with `mango` (basic regex) in all input lines and print the result to `stdout`:\n\n`{{command}} | sed 's/apple/mango/g'`\n\n- Replace all `apple` (extended regex) occurrences with `APPLE` (extended regex) in all input lines and print the result to `stdout`:\n\n`{{command}} | sed -E 's/(apple)/\U\1/g'`\n\n- Replace all `apple` (basic regex) occurrences with `mango` (basic regex) in a specific file and overwrite the original file in place:\n\n`sed -i 's/apple/mango/g' {{path/to/file}}`\n\n- Execute a specific script [f]ile and print the result to `stdout`:\n\n`{{command}} | sed -f {{path/to/script.sed}}`\n\n- Print just the first line to `stdout`:\n\n`{{command}} | sed -n '1p'`\n\n- [d]elete the first line of a file:\n\n`sed -i 1d {{path/to/file}}`\n\n- [i]nsert a new line at the first line of a file:\n\n`sed -i '1i\your new line text\' {{path/to/file}}`\n Task: Cut all remote paths from HTTP URLs received from standard input (one per line) keeping only the protocol identifier, host name, and trailing slash, of the form http://example.com/ Bash Command:<START>sed -n 's;\(http://[^/]*/\).*;\1;p'<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: sed(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training sed(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | COMMAND SYNOPSIS | REGULAR EXPRESSIONS | BUGS | AUTHOR | COPYRIGHT | SEE ALSO | COLOPHON SED(1) User Commands SED(1) NAME top sed - stream editor for filtering and transforming text SYNOPSIS top sed [-V] [--version] [--help] [-n] [--quiet] [--silent] [-l N] [--line-length=N] [-u] [--unbuffered] [-E] [-r] [--regexp-extended] [-e script] [--expression=script] [-f script-file] [--file=script-file] [script-if-no-other-script] [file...] DESCRIPTION top Sed is a stream editor. A stream editor is used to perform basic text transformations on an input stream (a file or input from a pipeline). While in some ways similar to an editor which permits scripted edits (such as ed), sed works by making only one pass over the input(s), and is consequently more efficient. But it is sed's ability to filter text in a pipeline which particularly distinguishes it from other types of editors. -n, --quiet, --silent suppress automatic printing of pattern space --debug annotate program execution -e script, --expression=script add the script to the commands to be executed -f script-file, --file=script-file add the contents of script-file to the commands to be executed --follow-symlinks follow symlinks when processing in place -i[SUFFIX], --in-place[=SUFFIX] edit files in place (makes backup if SUFFIX supplied) -l N, --line-length=N specify the desired line-wrap length for the `l' command --posix disable all GNU extensions. -E, -r, --regexp-extended use extended regular expressions in the script (for portability use POSIX -E). -s, --separate consider files as separate rather than as a single, continuous long stream. --sandbox operate in sandbox mode (disable e/r/w commands). -u, --unbuffered load minimal amounts of data from the input files and flush the output buffers more often -z, --null-data separate lines by NUL characters --help display this help and exit --version output version information and exit If no -e, --expression, -f, or --file option is given, then the first non-option argument is taken as the sed script to interpret. All remaining arguments are names of input files; if no input files are specified, then the standard input is read. GNU sed home page: <https://www.gnu.org/software/sed/>. General help using GNU software: <https://www.gnu.org/gethelp/>. E-mail bug reports to: <bug-sed@gnu.org>. COMMAND SYNOPSIS top This is just a brief synopsis of sed commands to serve as a reminder to those who already know sed; other documentation (such as the texinfo document) must be consulted for fuller descriptions. Zero-address ``commands'' : label Label for b and t commands. #comment The comment extends until the next newline (or the end of a -e script fragment). } The closing bracket of a { } block. Zero- or One- address commands = Print the current line number. a \ text Append text, which has each embedded newline preceded by a backslash. i \ text Insert text, which has each embedded newline preceded by a backslash. q [exit-code] Immediately quit the sed script without processing any more input, except that if auto-print is not disabled the current pattern space will be printed. The exit code argument is a GNU extension. Q [exit-code] Immediately quit the sed script without processing any more input. This is a GNU extension. r filename Append text read from filename. R filename Append a line read from filename. Each invocation of the command reads a line from the file. This is a GNU extension. Commands which accept address ranges { Begin a block of commands (end with a }). b label Branch to label; if label is omitted, branch to end of script. c \ text Replace the selected lines with text, which has each embedded newline preceded by a backslash. d Delete pattern space. Start next cycle. D If pattern space contains no newline, start a normal new cycle as if the d command was issued. Otherwise, delete text in the pattern space up to the first newline, and restart cycle with the resultant pattern space, without reading a new line of input. h H Copy/append pattern space to hold space. g G Copy/append hold space to pattern space. l List out the current line in a ``visually unambiguous'' form. l width List out the current line in a ``visually unambiguous'' form, breaking it at width characters. This is a GNU extension. n N Read/append the next line of input into the pattern space. p Print the current pattern space. P Print up to the first embedded newline of the current pattern space. s/regexp/replacement/ Attempt to match regexp against the pattern space. If successful, replace that portion matched with replacement. The replacement may contain the special character & to refer to that portion of the pattern space which matched, and the special escapes \1 through \9 to refer to the corresponding matching sub-expressions in the regexp. t label If a s/// has done a successful substitution since the last input line was read and since the last t or T command, then branch to label; if label is omitted, branch to end of script. T label If no s/// has done a successful substitution since the last input line was read and since the last t or T command, then branch to label; if label is omitted, branch to end of script. This is a GNU extension. w filename Write the current pattern space to filename. W filename Write the first line of the current pattern space to filename. This is a GNU extension. x Exchange the contents of the hold and pattern spaces. y/source/dest/ Transliterate the characters in the pattern space which appear in source to the corresponding character in dest. Addresses Sed commands can be given with no addresses, in which case the command will be executed for all input lines; with one address, in which case the command will only be executed for input lines which match that address; or with two addresses, in which case the command will be executed for all input lines which match the inclusive range of lines starting from the first address and continuing to the second address. Three things to note about address ranges: the syntax is addr1,addr2 (i.e., the addresses are separated by a comma); the line which addr1 matched will always be accepted, even if addr2 selects an earlier line; and if addr2 is a regexp, it will not be tested against the line that addr1 matched. After the address (or address-range), and before the command, a ! may be inserted, which specifies that the command shall only be executed if the address (or address-range) does not match. The following address types are supported: number Match only the specified line number (which increments cumulatively across files, unless the -s option is specified on the command line). first~step Match every step'th line starting with line first. For example, ``sed -n 1~2p'' will print all the odd-numbered lines in the input stream, and the address 2~5 will match every fifth line, starting with the second. first can be zero; in this case, sed operates as if it were equal to step. (This is an extension.) $ Match the last line. /regexp/ Match lines matching the regular expression regexp. Matching is performed on the current pattern space, which can be modified with commands such as ``s///''. \cregexpc Match lines matching the regular expression regexp. The c may be any character. GNU sed also supports some special 2-address forms: 0,addr2 Start out in "matched first address" state, until addr2 is found. This is similar to 1,addr2, except that if addr2 matches the very first line of input the 0,addr2 form will be at the end of its range, whereas the 1,addr2 form will still be at the beginning of its range. This works only when addr2 is a regular expression. addr1,+N Will match addr1 and the N lines following addr1. addr1,~N Will match addr1 and the lines following addr1 until the next line whose input line number is a multiple of N. REGULAR EXPRESSIONS top POSIX.2 BREs should be supported, but they aren't completely because of performance problems. The \n sequence in a regular expression matches the newline character, and similarly for \a, \t, and other sequences. The -E option switches to using extended regular expressions instead; it has been supported for years by GNU sed, and is now included in POSIX. BUGS top E-mail bug reports to bug-sed@gnu.org. Also, please include the output of ``sed --version'' in the body of your report if at all possible. AUTHOR top Written by Jay Fenlason, Tom Lord, Ken Pizzini, Paolo Bonzini, Jim Meyering, and Assaf Gordon. This sed program was built with SELinux support. SELinux is enabled on this system. GNU sed home page: <https://www.gnu.org/software/sed/>. General help using GNU software: <https://www.gnu.org/gethelp/>. E-mail bug reports to: <bug-sed@gnu.org>. COPYRIGHT top Copyright 2022 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top awk(1), ed(1), grep(1), tr(1), perlre(1), sed.info, any of various books on sed, the sed FAQ (http://sed.sf.net/grabbag/tutorials/sedfaq.txt), http://sed.sf.net/grabbag/. The full documentation for sed is maintained as a Texinfo manual. If the info and sed programs are properly installed at your site, the command info sed should give you access to the complete manual. COLOPHON top This page is part of the sed (stream-oriented editor) project. Information about the project can be found at http://www.gnu.org/software/sed/. If you have a bug report for this manual page, send it to bug-sed@gnu.org. This page was obtained from the tarball sed-4.9.tar.gz fetched from https://www.gnu.org/software/sed/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU sed 4.9 November 2022 SED(1) Pages that refer to this page: gawk(1), grep(1), iostat2pcp(1), pmdaopenmetrics(1), pmlogrewrite(1), sheet2pcp(1), cpuset(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Cut all remote paths from HTTP URLs received from standard input (one per line) keeping only the protocol identifier, host name, and trailing slash, of the form http://example.com/ Bash Command:<START>sed -n 's;\(http://[^/]*/\).*;\1;p'<END>

Cuts off last part from the path $dir, and deletes resulted folder if empty.

rmdir "$(dirname $dir)"

['dirname', 'rmdir']

Output a Bash command to accomplish the following task. Task: Cuts off last part from the path $dir, and deletes resulted folder if empty. Bash Command:<START>rmdir "$(dirname $dir)"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # dirname\n\n> Calculates the parent directory of a file or directory path.\n> More information: <https://www.gnu.org/software/coreutils/dirname>.\n\n- Calculate the parent directory of a given path:\n\n`dirname {{path/to/file_or_directory}}`\n\n- Calculate the parent directory of multiple paths:\n\n`dirname {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n\n- Delimit output with a NUL character instead of a newline (useful when combining with `xargs`):\n\n`dirname --zero {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n # rmdir\n\n> Remove directories without files.\n> See also: `rm`.\n> More information: <https://www.gnu.org/software/coreutils/rmdir>.\n\n- Remove specific directories:\n\n`rmdir {{path/to/directory1 path/to/directory2 ...}}`\n\n- Remove specific nested directories recursively:\n\n`rmdir --parents {{path/to/directory1 path/to/directory2 ...}}`\n Task: Cuts off last part from the path $dir, and deletes resulted folder if empty. Bash Command:<START>rmdir "$(dirname $dir)"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: dirname(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training dirname(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | EXAMPLES | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON DIRNAME(1) User Commands DIRNAME(1) NAME top dirname - strip last component from file name SYNOPSIS top dirname [OPTION] NAME... DESCRIPTION top Output each NAME with its last non-slash component and trailing slashes removed; if NAME contains no /'s, output '.' (meaning the current directory). -z, --zero end each output line with NUL, not newline --help display this help and exit --version output version information and exit EXAMPLES top dirname /usr/bin/ -> "/usr" dirname dir1/str dir2/str -> "dir1" followed by "dir2" dirname stdio.h -> "." AUTHOR top Written by David MacKenzie and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top basename(1), readlink(1) Full documentation <https://www.gnu.org/software/coreutils/dirname> or available locally via: info '(coreutils) dirname invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 DIRNAME(1) Pages that refer to this page: basename(1), basename(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rmdir(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rmdir(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RMDIR(1) User Commands RMDIR(1) NAME top rmdir - remove empty directories SYNOPSIS top rmdir [OPTION]... DIRECTORY... DESCRIPTION top Remove the DIRECTORY(ies), if they are empty. --ignore-fail-on-non-empty ignore each failure to remove a non-empty directory -p, --parents remove DIRECTORY and its ancestors; e.g., 'rmdir -p a/b' is similar to 'rmdir a/b a' -v, --verbose output a diagnostic for every directory processed --help display this help and exit --version output version information and exit AUTHOR top Written by David MacKenzie. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top rmdir(2) Full documentation <https://www.gnu.org/software/coreutils/rmdir> or available locally via: info '(coreutils) rmdir invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RMDIR(1) Pages that refer to this page: rmdir(2), cpuset(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Cuts off last part from the path $dir, and deletes resulted folder if empty. Bash Command:<START>rmdir "$(dirname $dir)"<END>

Cuts off last two parts from the path $dir, and deletes resulted folder if empty.

rmdir "$(dirname $(dirname $dir))"

['dirname', 'rmdir']

Output a Bash command to accomplish the following task. Task: Cuts off last two parts from the path $dir, and deletes resulted folder if empty. Bash Command:<START>rmdir "$(dirname $(dirname $dir))"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # dirname\n\n> Calculates the parent directory of a file or directory path.\n> More information: <https://www.gnu.org/software/coreutils/dirname>.\n\n- Calculate the parent directory of a given path:\n\n`dirname {{path/to/file_or_directory}}`\n\n- Calculate the parent directory of multiple paths:\n\n`dirname {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n\n- Delimit output with a NUL character instead of a newline (useful when combining with `xargs`):\n\n`dirname --zero {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n # rmdir\n\n> Remove directories without files.\n> See also: `rm`.\n> More information: <https://www.gnu.org/software/coreutils/rmdir>.\n\n- Remove specific directories:\n\n`rmdir {{path/to/directory1 path/to/directory2 ...}}`\n\n- Remove specific nested directories recursively:\n\n`rmdir --parents {{path/to/directory1 path/to/directory2 ...}}`\n Task: Cuts off last two parts from the path $dir, and deletes resulted folder if empty. Bash Command:<START>rmdir "$(dirname $(dirname $dir))"<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: dirname(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training dirname(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | EXAMPLES | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON DIRNAME(1) User Commands DIRNAME(1) NAME top dirname - strip last component from file name SYNOPSIS top dirname [OPTION] NAME... DESCRIPTION top Output each NAME with its last non-slash component and trailing slashes removed; if NAME contains no /'s, output '.' (meaning the current directory). -z, --zero end each output line with NUL, not newline --help display this help and exit --version output version information and exit EXAMPLES top dirname /usr/bin/ -> "/usr" dirname dir1/str dir2/str -> "dir1" followed by "dir2" dirname stdio.h -> "." AUTHOR top Written by David MacKenzie and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top basename(1), readlink(1) Full documentation <https://www.gnu.org/software/coreutils/dirname> or available locally via: info '(coreutils) dirname invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 DIRNAME(1) Pages that refer to this page: basename(1), basename(3) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rmdir(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rmdir(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RMDIR(1) User Commands RMDIR(1) NAME top rmdir - remove empty directories SYNOPSIS top rmdir [OPTION]... DIRECTORY... DESCRIPTION top Remove the DIRECTORY(ies), if they are empty. --ignore-fail-on-non-empty ignore each failure to remove a non-empty directory -p, --parents remove DIRECTORY and its ancestors; e.g., 'rmdir -p a/b' is similar to 'rmdir a/b a' -v, --verbose output a diagnostic for every directory processed --help display this help and exit --version output version information and exit AUTHOR top Written by David MacKenzie. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top rmdir(2) Full documentation <https://www.gnu.org/software/coreutils/rmdir> or available locally via: info '(coreutils) rmdir invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RMDIR(1) Pages that refer to this page: rmdir(2), cpuset(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Cuts off last two parts from the path $dir, and deletes resulted folder if empty. Bash Command:<START>rmdir "$(dirname $(dirname $dir))"<END>

Decompress "file2.txt" and "file1.txt" and print lines in "file1.txt" that match the 5th tab separated field in "file2.txt"

awk -F'\t' 'NR==FNR{a[$5];next} $5 in a' <(zcat file2.txt) <(zcat file1.txt)

['awk', 'zcat']

Output a Bash command to accomplish the following task. Task: Decompress "file2.txt" and "file1.txt" and print lines in "file1.txt" that match the 5th tab separated field in "file2.txt" Bash Command:<START>awk -F'\t' 'NR==FNR{a[$5];next} $5 in a' <(zcat file2.txt) <(zcat file1.txt)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # awk\n\n> A versatile programming language for working on files.\n> More information: <https://github.com/onetrueawk/awk>.\n\n- Print the fifth column (a.k.a. field) in a space-separated file:\n\n`awk '{print $5}' {{path/to/file}}`\n\n- Print the second column of the lines containing "foo" in a space-separated file:\n\n`awk '/{{foo}}/ {print $2}' {{path/to/file}}`\n\n- Print the last column of each line in a file, using a comma (instead of space) as a field separator:\n\n`awk -F ',' '{print $NF}' {{path/to/file}}`\n\n- Sum the values in the first column of a file and print the total:\n\n`awk '{s+=$1} END {print s}' {{path/to/file}}`\n\n- Print every third line starting from the first line:\n\n`awk 'NR%3==1' {{path/to/file}}`\n\n- Print different values based on conditions:\n\n`awk '{if ($1 == "foo") print "Exact match foo"; else if ($1 ~ "bar") print "Partial match bar"; else print "Baz"}' {{path/to/file}}`\n\n- Print all lines where the 10th column value equals the specified value:\n\n`awk '($10 == {{value}})'`\n\n- Print all the lines which the 10th column value is between a min and a max:\n\n`awk '($10 >= {{min_value}} && $10 <= {{max_value}})'`\n # zcat\n\n> Print data from `gzip` compressed files.\n> More information: <https://www.gnu.org/software/gzip/manual/gzip.html>.\n\n- Print the uncompressed contents of a `gzip` archive to `stdout`:\n\n`zcat {{file.txt.gz}}`\n\n- Print compression details of a `gzip` archive to `stdout`:\n\n`zcat -l {{file.txt.gz}}`\n Task: Decompress "file2.txt" and "file1.txt" and print lines in "file1.txt" that match the 5th tab separated field in "file2.txt" Bash Command:<START>awk -F'\t' 'NR==FNR{a[$5];next} $5 in a' <(zcat file2.txt) <(zcat file1.txt)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: awk(1p) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training awk(1p) Linux manual page PROLOG | NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | STDIN | INPUT FILES | ENVIRONMENT VARIABLES | ASYNCHRONOUS EVENTS | STDOUT | STDERR | OUTPUT FILES | EXTENDED DESCRIPTION | EXIT STATUS | CONSEQUENCES OF ERRORS | APPLICATION USAGE | EXAMPLES | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT AWK(1P) POSIX Programmer's Manual AWK(1P) PROLOG top This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux. NAME top awk pattern scanning and processing language SYNOPSIS top awk [-F sepstring] [-v assignment]... program [argument...] awk [-F sepstring] -f progfile [-f progfile]... [-v assignment]... [argument...] DESCRIPTION top The awk utility shall execute programs written in the awk programming language, which is specialized for textual data manipulation. An awk program is a sequence of patterns and corresponding actions. When input is read that matches a pattern, the action associated with that pattern is carried out. Input shall be interpreted as a sequence of records. By default, a record is a line, less its terminating <newline>, but this can be changed by using the RS built-in variable. Each record of input shall be matched in turn against each pattern in the program. For each pattern matched, the associated action shall be executed. The awk utility shall interpret each input record as a sequence of fields where, by default, a field is a string of non-<blank> non-<newline> characters. This default <blank> and <newline> field delimiter can be changed by using the FS built-in variable or the -F sepstring option. The awk utility shall denote the first field in a record $1, the second $2, and so on. The symbol $0 shall refer to the entire record; setting any other field causes the re-evaluation of $0. Assigning to $0 shall reset the values of all other fields and the NF built-in variable. OPTIONS top The awk utility shall conform to the Base Definitions volume of POSIX.12017, Section 12.2, Utility Syntax Guidelines. The following options shall be supported: -F sepstring Define the input field separator. This option shall be equivalent to: -v FS=sepstring except that if -F sepstring and -v FS=sepstring are both used, it is unspecified whether the FS assignment resulting from -F sepstring is processed in command line order or is processed after the last -v FS=sepstring. See the description of the FS built-in variable, and how it is used, in the EXTENDED DESCRIPTION section. -f progfile Specify the pathname of the file progfile containing an awk program. A pathname of '-' shall denote the standard input. If multiple instances of this option are specified, the concatenation of the files specified as progfile in the order specified shall be the awk program. The awk program can alternatively be specified in the command line as a single argument. -v assignment The application shall ensure that the assignment argument is in the same form as an assignment operand. The specified variable assignment shall occur prior to executing the awk program, including the actions associated with BEGIN patterns (if any). Multiple occurrences of this option can be specified. OPERANDS top The following operands shall be supported: program If no -f option is specified, the first operand to awk shall be the text of the awk program. The application shall supply the program operand as a single argument to awk. If the text does not end in a <newline>, awk shall interpret the text as if it did. argument Either of the following two types of argument can be intermixed: file A pathname of a file that contains the input to be read, which is matched against the set of patterns in the program. If no file operands are specified, or if a file operand is '-', the standard input shall be used. assignment An operand that begins with an <underscore> or alphabetic character from the portable character set (see the table in the Base Definitions volume of POSIX.12017, Section 6.1, Portable Character Set), followed by a sequence of underscores, digits, and alphabetics from the portable character set, followed by the '=' character, shall specify a variable assignment rather than a pathname. The characters before the '=' represent the name of an awk variable; if that name is an awk reserved word (see Grammar) the behavior is undefined. The characters following the <equals-sign> shall be interpreted as if they appeared in the awk program preceded and followed by a double-quote ('"') character, as a STRING token (see Grammar), except that if the last character is an unescaped <backslash>, it shall be interpreted as a literal <backslash> rather than as the first character of the sequence "\"". The variable shall be assigned the value of that STRING token and, if appropriate, shall be considered a numeric string (see Expressions in awk), the variable shall also be assigned its numeric value. Each such variable assignment shall occur just prior to the processing of the following file, if any. Thus, an assignment before the first file argument shall be executed after the BEGIN actions (if any), while an assignment after the last file argument shall occur before the END actions (if any). If there are no file arguments, assignments shall be executed before processing the standard input. STDIN top The standard input shall be used only if no file operands are specified, or if a file operand is '-', or if a progfile option- argument is '-'; see the INPUT FILES section. If the awk program contains no actions and no patterns, but is otherwise a valid awk program, standard input and any file operands shall not be read and awk shall exit with a return status of zero. INPUT FILES top Input files to the awk program from any of the following sources shall be text files: * Any file operands or their equivalents, achieved by modifying the awk variables ARGV and ARGC * Standard input in the absence of any file operands * Arguments to the getline function Whether the variable RS is set to a value other than a <newline> or not, for these files, implementations shall support records terminated with the specified separator up to {LINE_MAX} bytes and may support longer records. If -f progfile is specified, the application shall ensure that the files named by each of the progfile option-arguments are text files and their concatenation, in the same order as they appear in the arguments, is an awk program. ENVIRONMENT VARIABLES top The following environment variables shall affect the execution of awk: LANG Provide a default value for the internationalization variables that are unset or null. (See the Base Definitions volume of POSIX.12017, Section 8.2, Internationalization Variables for the precedence of internationalization variables used to determine the values of locale categories.) LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE Determine the locale for the behavior of ranges, equivalence classes, and multi-character collating elements within regular expressions and in comparisons of string values. LC_CTYPE Determine the locale for the interpretation of sequences of bytes of text data as characters (for example, single-byte as opposed to multi-byte characters in arguments and input files), the behavior of character classes within regular expressions, the identification of characters as letters, and the mapping of uppercase and lowercase characters for the toupper and tolower functions. LC_MESSAGES Determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error. LC_NUMERIC Determine the radix character used when interpreting numeric input, performing conversions between numeric and string values, and formatting numeric output. Regardless of locale, the <period> character (the decimal-point character of the POSIX locale) is the decimal-point character recognized in processing awk programs (including assignments in command line arguments). NLSPATH Determine the location of message catalogs for the processing of LC_MESSAGES. PATH Determine the search path when looking for commands executed by system(expr), or input and output pipes; see the Base Definitions volume of POSIX.12017, Chapter 8, Environment Variables. In addition, all environment variables shall be visible via the awk variable ENVIRON. ASYNCHRONOUS EVENTS top Default. STDOUT top The nature of the output files depends on the awk program. STDERR top The standard error shall be used only for diagnostic messages. OUTPUT FILES top The nature of the output files depends on the awk program. EXTENDED DESCRIPTION top Overall Program Structure An awk program is composed of pairs of the form: pattern { action } Either the pattern or the action (including the enclosing brace characters) can be omitted. A missing pattern shall match any record of input, and a missing action shall be equivalent to: { print } Execution of the awk program shall start by first executing the actions associated with all BEGIN patterns in the order they occur in the program. Then each file operand (or standard input if no files were specified) shall be processed in turn by reading data from the file until a record separator is seen (<newline> by default). Before the first reference to a field in the record is evaluated, the record shall be split into fields, according to the rules in Regular Expressions, using the value of FS that was current at the time the record was read. Each pattern in the program then shall be evaluated in the order of occurrence, and the action associated with each pattern that matches the current record executed. The action for a matching pattern shall be executed before evaluating subsequent patterns. Finally, the actions associated with all END patterns shall be executed in the order they occur in the program. Expressions in awk Expressions describe computations used in patterns and actions. In the following table, valid expression operations are given in groups from highest precedence first to lowest precedence last, with equal-precedence operators grouped between horizontal lines. In expression evaluation, where the grammar is formally ambiguous, higher precedence operators shall be evaluated before lower precedence operators. In this table expr, expr1, expr2, and expr3 represent any expression, while lvalue represents any entity that can be assigned to (that is, on the left side of an assignment operator). The precise syntax of expressions is given in Grammar. Table 4-1: Expressions in Decreasing Precedence in awk Syntax Name Type of Result Associativity ( expr ) Grouping Type of expr N/A $expr Field reference String N/A lvalue ++ Post-increment Numeric N/A lvalue -- Post-decrement Numeric N/A ++ lvalue Pre-increment Numeric N/A -- lvalue Pre-decrement Numeric N/A expr ^ expr Exponentiation Numeric Right ! expr Logical not Numeric N/A + expr Unary plus Numeric N/A - expr Unary minus Numeric N/A expr * expr Multiplication Numeric Left expr / expr Division Numeric Left expr % expr Modulus Numeric Left expr + expr Addition Numeric Left expr - expr Subtraction Numeric Left expr expr String concatenation String Left expr < expr Less than Numeric None expr <= expr Less than or equal to Numeric None expr != expr Not equal to Numeric None expr == expr Equal to Numeric None expr > expr Greater than Numeric None expr >= expr Greater than or equal to Numeric None expr ~ expr ERE match Numeric None expr !~ expr ERE non-match Numeric None expr in array Array membership Numeric Left ( index ) in array Multi-dimension array Numeric Left membership expr && expr Logical AND Numeric Left expr || expr Logical OR Numeric Left expr1 ? expr2 : expr3Conditional expression Type of selectedRight expr2 or expr3 lvalue ^= expr Exponentiation assignmentNumeric Right lvalue %= expr Modulus assignment Numeric Right lvalue *= expr Multiplication assignmentNumeric Right lvalue /= expr Division assignment Numeric Right lvalue += expr Addition assignment Numeric Right lvalue -= expr Subtraction assignment Numeric Right lvalue = expr Assignment Type of expr Right Each expression shall have either a string value, a numeric value, or both. Except as stated for specific contexts, the value of an expression shall be implicitly converted to the type needed for the context in which it is used. A string value shall be converted to a numeric value either by the equivalent of the following calls to functions defined by the ISO C standard: setlocale(LC_NUMERIC, ""); numeric_value = atof(string_value); or by converting the initial portion of the string to type double representation as follows: The input string is decomposed into two parts: an initial, possibly empty, sequence of white-space characters (as specified by isspace()) and a subject sequence interpreted as a floating-point constant. The expected form of the subject sequence is an optional '+' or '-' sign, then a non-empty sequence of digits optionally containing a <period>, then an optional exponent part. An exponent part consists of 'e' or 'E', followed by an optional sign, followed by one or more decimal digits. The sequence starting with the first digit or the <period> (whichever occurs first) is interpreted as a floating constant of the C language, and if neither an exponent part nor a <period> appears, a <period> is assumed to follow the last digit in the string. If the subject sequence begins with a <hyphen-minus>, the value resulting from the conversion is negated. A numeric value that is exactly equal to the value of an integer (see Section 1.1.2, Concepts Derived from the ISO C Standard) shall be converted to a string by the equivalent of a call to the sprintf function (see String Functions) with the string "%d" as the fmt argument and the numeric value being converted as the first and only expr argument. Any other numeric value shall be converted to a string by the equivalent of a call to the sprintf function with the value of the variable CONVFMT as the fmt argument and the numeric value being converted as the first and only expr argument. The result of the conversion is unspecified if the value of CONVFMT is not a floating-point format specification. This volume of POSIX.12017 specifies no explicit conversions between numbers and strings. An application can force an expression to be treated as a number by adding zero to it, or can force it to be treated as a string by concatenating the null string ("") to it. A string value shall be considered a numeric string if it comes from one of the following: 1. Field variables 2. Input from the getline() function 3. FILENAME 4. ARGV array elements 5. ENVIRON array elements 6. Array elements created by the split() function 7. A command line variable assignment 8. Variable assignment from another numeric string variable and an implementation-dependent condition corresponding to either case (a) or (b) below is met. a. After the equivalent of the following calls to functions defined by the ISO C standard, string_value_end would differ from string_value, and any characters before the terminating null character in string_value_end would be <blank> characters: char *string_value_end; setlocale(LC_NUMERIC, ""); numeric_value = strtod (string_value, &string_value_end); b. After all the following conversions have been applied, the resulting string would lexically be recognized as a NUMBER token as described by the lexical conventions in Grammar: -- All leading and trailing <blank> characters are discarded. -- If the first non-<blank> is '+' or '-', it is discarded. -- Each occurrence of the decimal point character from the current locale is changed to a <period>. In case (a) the numeric value of the numeric string shall be the value that would be returned by the strtod() call. In case (b) if the first non-<blank> is '-', the numeric value of the numeric string shall be the negation of the numeric value of the recognized NUMBER token; otherwise, the numeric value of the numeric string shall be the numeric value of the recognized NUMBER token. Whether or not a string is a numeric string shall be relevant only in contexts where that term is used in this section. When an expression is used in a Boolean context, if it has a numeric value, a value of zero shall be treated as false and any other value shall be treated as true. Otherwise, a string value of the null string shall be treated as false and any other value shall be treated as true. A Boolean context shall be one of the following: * The first subexpression of a conditional expression * An expression operated on by logical NOT, logical AND, or logical OR * The second expression of a for statement * The expression of an if statement * The expression of the while clause in either a while or do...while statement * An expression used as a pattern (as in Overall Program Structure) All arithmetic shall follow the semantics of floating-point arithmetic as specified by the ISO C standard (see Section 1.1.2, Concepts Derived from the ISO C Standard). The value of the expression: expr1 ^ expr2 shall be equivalent to the value returned by the ISO C standard function call: pow(expr1, expr2) The expression: lvalue ^= expr shall be equivalent to the ISO C standard expression: lvalue = pow(lvalue, expr) except that lvalue shall be evaluated only once. The value of the expression: expr1 % expr2 shall be equivalent to the value returned by the ISO C standard function call: fmod(expr1, expr2) The expression: lvalue %= expr shall be equivalent to the ISO C standard expression: lvalue = fmod(lvalue, expr) except that lvalue shall be evaluated only once. Variables and fields shall be set by the assignment statement: lvalue = expression and the type of expression shall determine the resulting variable type. The assignment includes the arithmetic assignments ("+=", "-=", "*=", "/=", "%=", "^=", "++", "--") all of which shall produce a numeric result. The left-hand side of an assignment and the target of increment and decrement operators can be one of a variable, an array with index, or a field selector. The awk language supplies arrays that are used for storing numbers or strings. Arrays need not be declared. They shall initially be empty, and their sizes shall change dynamically. The subscripts, or element identifiers, are strings, providing a type of associative array capability. An array name followed by a subscript within square brackets can be used as an lvalue and thus as an expression, as described in the grammar; see Grammar. Unsubscripted array names can be used in only the following contexts: * A parameter in a function definition or function call * The NAME token following any use of the keyword in as specified in the grammar (see Grammar); if the name used in this context is not an array name, the behavior is undefined A valid array index shall consist of one or more <comma>-separated expressions, similar to the way in which multi- dimensional arrays are indexed in some programming languages. Because awk arrays are really one-dimensional, such a <comma>-separated list shall be converted to a single string by concatenating the string values of the separate expressions, each separated from the other by the value of the SUBSEP variable. Thus, the following two index operations shall be equivalent: var[expr1, expr2, ... exprn] var[expr1 SUBSEP expr2 SUBSEP ... SUBSEP exprn] The application shall ensure that a multi-dimensioned index used with the in operator is parenthesized. The in operator, which tests for the existence of a particular array element, shall not cause that element to exist. Any other reference to a nonexistent array element shall automatically create it. Comparisons (with the '<', "<=", "!=", "==", '>', and ">=" operators) shall be made numerically if both operands are numeric, if one is numeric and the other has a string value that is a numeric string, or if one is numeric and the other has the uninitialized value. Otherwise, operands shall be converted to strings as required and a string comparison shall be made as follows: * For the "!=" and "==" operators, the strings should be compared to check if they are identical but may be compared using the locale-specific collation sequence to check if they collate equally. * For the other operators, the strings shall be compared using the locale-specific collation sequence. The value of the comparison expression shall be 1 if the relation is true, or 0 if the relation is false. Variables and Special Variables Variables can be used in an awk program by referencing them. With the exception of function parameters (see User-Defined Functions), they are not explicitly declared. Function parameter names shall be local to the function; all other variable names shall be global. The same name shall not be used as both a function parameter name and as the name of a function or a special awk variable. The same name shall not be used both as a variable name with global scope and as the name of a function. The same name shall not be used within the same scope both as a scalar variable and as an array. Uninitialized variables, including scalar variables, array elements, and field variables, shall have an uninitialized value. An uninitialized value shall have both a numeric value of zero and a string value of the empty string. Evaluation of variables with an uninitialized value, to either string or numeric, shall be determined by the context in which they are used. Field variables shall be designated by a '$' followed by a number or numerical expression. The effect of the field number expression evaluating to anything other than a non-negative integer is unspecified; uninitialized variables or string values need not be converted to numeric values in this context. New field variables can be created by assigning a value to them. References to nonexistent fields (that is, fields after $NF), shall evaluate to the uninitialized value. Such references shall not create new fields. However, assigning to a nonexistent field (for example, $(NF+2)=5) shall increase the value of NF; create any intervening fields with the uninitialized value; and cause the value of $0 to be recomputed, with the fields being separated by the value of OFS. Each field variable shall have a string value or an uninitialized value when created. Field variables shall have the uninitialized value when created from $0 using FS and the variable does not contain any characters. If appropriate, the field variable shall be considered a numeric string (see Expressions in awk). Implementations shall support the following other special variables that are set by awk: ARGC The number of elements in the ARGV array. ARGV An array of command line arguments, excluding options and the program argument, numbered from zero to ARGC-1. The arguments in ARGV can be modified or added to; ARGC can be altered. As each input file ends, awk shall treat the next non-null element of ARGV, up to the current value of ARGC-1, inclusive, as the name of the next input file. Thus, setting an element of ARGV to null means that it shall not be treated as an input file. The name '-' indicates the standard input. If an argument matches the format of an assignment operand, this argument shall be treated as an assignment rather than a file argument. CONVFMT The printf format for converting numbers to strings (except for output statements, where OFMT is used); "%.6g" by default. ENVIRON An array representing the value of the environment, as described in the exec functions defined in the System Interfaces volume of POSIX.12017. The indices of the array shall be strings consisting of the names of the environment variables, and the value of each array element shall be a string consisting of the value of that variable. If appropriate, the environment variable shall be considered a numeric string (see Expressions in awk); the array element shall also have its numeric value. In all cases where the behavior of awk is affected by environment variables (including the environment of any commands that awk executes via the system function or via pipeline redirections with the print statement, the printf statement, or the getline function), the environment used shall be the environment at the time awk began executing; it is implementation-defined whether any modification of ENVIRON affects this environment. FILENAME A pathname of the current input file. Inside a BEGIN action the value is undefined. Inside an END action the value shall be the name of the last input file processed. FNR The ordinal number of the current record in the current file. Inside a BEGIN action the value shall be zero. Inside an END action the value shall be the number of the last record processed in the last file processed. FS Input field separator regular expression; a <space> by default. NF The number of fields in the current record. Inside a BEGIN action, the use of NF is undefined unless a getline function without a var argument is executed previously. Inside an END action, NF shall retain the value it had for the last record read, unless a subsequent, redirected, getline function without a var argument is performed prior to entering the END action. NR The ordinal number of the current record from the start of input. Inside a BEGIN action the value shall be zero. Inside an END action the value shall be the number of the last record processed. OFMT The printf format for converting numbers to strings in output statements (see Output Statements); "%.6g" by default. The result of the conversion is unspecified if the value of OFMT is not a floating-point format specification. OFS The print statement output field separator; <space> by default. ORS The print statement output record separator; a <newline> by default. RLENGTH The length of the string matched by the match function. RS The first character of the string value of RS shall be the input record separator; a <newline> by default. If RS contains more than one character, the results are unspecified. If RS is null, then records are separated by sequences consisting of a <newline> plus one or more blank lines, leading or trailing blank lines shall not result in empty records at the beginning or end of the input, and a <newline> shall always be a field separator, no matter what the value of FS is. RSTART The starting position of the string matched by the match function, numbering from 1. This shall always be equivalent to the return value of the match function. SUBSEP The subscript separator string for multi-dimensional arrays; the default value is implementation-defined. Regular Expressions The awk utility shall make use of the extended regular expression notation (see the Base Definitions volume of POSIX.12017, Section 9.4, Extended Regular Expressions) except that it shall allow the use of C-language conventions for escaping special characters within the EREs, as specified in the table in the Base Definitions volume of POSIX.12017, Chapter 5, File Format Notation ('\\', '\a', '\b', '\f', '\n', '\r', '\t', '\v') and the following table; these escape sequences shall be recognized both inside and outside bracket expressions. Note that records need not be separated by <newline> characters and string constants can contain <newline> characters, so even the "\n" sequence is valid in awk EREs. Using a <slash> character within an ERE requires the escaping shown in the following table. Table 4-2: Escape Sequences in awk Escape Sequence Description Meaning \" <backslash> <quotation-mark> <quotation-mark> character \/ <backslash> <slash> <slash> character \ddd A <backslash> character followed The character whose encoding is by the longest sequence of one, represented by the one, two, or two, or three octal-digit three-digit octal integer. Multi- characters (01234567). If all of byte characters require multiple, the digits are 0 (that is, concatenated escape sequences of representation of the NUL this type, including the leading character), the behavior is <backslash> for each byte. undefined. \c A <backslash> character followed Undefined by any character not described in this table or in the table in the Base Definitions volume of POSIX.12017, Chapter 5, File Format Notation ('\\', '\a', '\b', '\f', '\n', '\r', '\t', '\v'). A regular expression can be matched against a specific field or string by using one of the two regular expression matching operators, '~' and "!~". These operators shall interpret their right-hand operand as a regular expression and their left-hand operand as a string. If the regular expression matches the string, the '~' expression shall evaluate to a value of 1, and the "!~" expression shall evaluate to a value of 0. (The regular expression matching operation is as defined by the term matched in the Base Definitions volume of POSIX.12017, Section 9.1, Regular Expression Definitions, where a match occurs on any part of the string unless the regular expression is limited with the <circumflex> or <dollar-sign> special characters.) If the regular expression does not match the string, the '~' expression shall evaluate to a value of 0, and the "!~" expression shall evaluate to a value of 1. If the right-hand operand is any expression other than the lexical token ERE, the string value of the expression shall be interpreted as an extended regular expression, including the escape conventions described above. Note that these same escape conventions shall also be applied in determining the value of a string literal (the lexical token STRING), and thus shall be applied a second time when a string literal is used in this context. When an ERE token appears as an expression in any context other than as the right-hand of the '~' or "!~" operator or as one of the built-in function arguments described below, the value of the resulting expression shall be the equivalent of: $0 ~ /ere/ The ere argument to the gsub, match, sub functions, and the fs argument to the split function (see String Functions) shall be interpreted as extended regular expressions. These can be either ERE tokens or arbitrary expressions, and shall be interpreted in the same manner as the right-hand side of the '~' or "!~" operator. An extended regular expression can be used to separate fields by assigning a string containing the expression to the built-in variable FS, either directly or as a consequence of using the -F sepstring option. The default value of the FS variable shall be a single <space>. The following describes FS behavior: 1. If FS is a null string, the behavior is unspecified. 2. If FS is a single character: a. If FS is <space>, skip leading and trailing <blank> and <newline> characters; fields shall be delimited by sets of one or more <blank> or <newline> characters. b. Otherwise, if FS is any other character c, fields shall be delimited by each single occurrence of c. 3. Otherwise, the string value of FS shall be considered to be an extended regular expression. Each occurrence of a sequence matching the extended regular expression shall delimit fields. Except for the '~' and "!~" operators, and in the gsub, match, split, and sub built-in functions, ERE matching shall be based on input records; that is, record separator characters (the first character of the value of the variable RS, <newline> by default) cannot be embedded in the expression, and no expression shall match the record separator character. If the record separator is not <newline>, <newline> characters embedded in the expression can be matched. For the '~' and "!~" operators, and in those four built-in functions, ERE matching shall be based on text strings; that is, any character (including <newline> and the record separator) can be embedded in the pattern, and an appropriate pattern shall match any character. However, in all awk ERE matching, the use of one or more NUL characters in the pattern, input record, or text string produces undefined results. Patterns A pattern is any valid expression, a range specified by two expressions separated by a comma, or one of the two special patterns BEGIN or END. Special Patterns The awk utility shall recognize two special patterns, BEGIN and END. Each BEGIN pattern shall be matched once and its associated action executed before the first record of input is readexcept possibly by use of the getline function (see Input/Output and General Functions) in a prior BEGIN actionand before command line assignment is done. Each END pattern shall be matched once and its associated action executed after the last record of input has been read. These two patterns shall have associated actions. BEGIN and END shall not combine with other patterns. Multiple BEGIN and END patterns shall be allowed. The actions associated with the BEGIN patterns shall be executed in the order specified in the program, as are the END actions. An END pattern can precede a BEGIN pattern in a program. If an awk program consists of only actions with the pattern BEGIN, and the BEGIN action contains no getline function, awk shall exit without reading its input when the last statement in the last BEGIN action is executed. If an awk program consists of only actions with the pattern END or only actions with the patterns BEGIN and END, the input shall be read before the statements in the END actions are executed. Expression Patterns An expression pattern shall be evaluated as if it were an expression in a Boolean context. If the result is true, the pattern shall be considered to match, and the associated action (if any) shall be executed. If the result is false, the action shall not be executed. Pattern Ranges A pattern range consists of two expressions separated by a comma; in this case, the action shall be performed for all records between a match of the first expression and the following match of the second expression, inclusive. At this point, the pattern range can be repeated starting at input records subsequent to the end of the matched range. Actions An action is a sequence of statements as shown in the grammar in Grammar. Any single statement can be replaced by a statement list enclosed in curly braces. The application shall ensure that statements in a statement list are separated by <newline> or <semicolon> characters. Statements in a statement list shall be executed sequentially in the order that they appear. The expression acting as the conditional in an if statement shall be evaluated and if it is non-zero or non-null, the following statement shall be executed; otherwise, if else is present, the statement following the else shall be executed. The if, while, do...while, for, break, and continue statements are based on the ISO C standard (see Section 1.1.2, Concepts Derived from the ISO C Standard), except that the Boolean expressions shall be treated as described in Expressions in awk, and except in the case of: for (variable in array) which shall iterate, assigning each index of array to variable in an unspecified order. The results of adding new elements to array within such a for loop are undefined. If a break or continue statement occurs outside of a loop, the behavior is undefined. The delete statement shall remove an individual array element. Thus, the following code deletes an entire array: for (index in array) delete array[index] The next statement shall cause all further processing of the current input record to be abandoned. The behavior is undefined if a next statement appears or is invoked in a BEGIN or END action. The exit statement shall invoke all END actions in the order in which they occur in the program source and then terminate the program without reading further input. An exit statement inside an END action shall terminate the program without further execution of END actions. If an expression is specified in an exit statement, its numeric value shall be the exit status of awk, unless subsequent errors are encountered or a subsequent exit statement with an expression is executed. Output Statements Both print and printf statements shall write to standard output by default. The output shall be written to the location specified by output_redirection if one is supplied, as follows: > expression >> expression | expression In all cases, the expression shall be evaluated to produce a string that is used as a pathname into which to write (for '>' or ">>") or as a command to be executed (for '|'). Using the first two forms, if the file of that name is not currently open, it shall be opened, creating it if necessary and using the first form, truncating the file. The output then shall be appended to the file. As long as the file remains open, subsequent calls in which expression evaluates to the same string value shall simply append output to the file. The file remains open until the close function (see Input/Output and General Functions) is called with an expression that evaluates to the same string value. The third form shall write output onto a stream piped to the input of a command. The stream shall be created if no stream is currently open with the value of expression as its command name. The stream created shall be equivalent to one created by a call to the popen() function defined in the System Interfaces volume of POSIX.12017 with the value of expression as the command argument and a value of w as the mode argument. As long as the stream remains open, subsequent calls in which expression evaluates to the same string value shall write output to the existing stream. The stream shall remain open until the close function (see Input/Output and General Functions) is called with an expression that evaluates to the same string value. At that time, the stream shall be closed as if by a call to the pclose() function defined in the System Interfaces volume of POSIX.12017. As described in detail by the grammar in Grammar, these output statements shall take a <comma>-separated list of expressions referred to in the grammar by the non-terminal symbols expr_list, print_expr_list, or print_expr_list_opt. This list is referred to here as the expression list, and each member is referred to as an expression argument. The print statement shall write the value of each expression argument onto the indicated output stream separated by the current output field separator (see variable OFS above), and terminated by the output record separator (see variable ORS above). All expression arguments shall be taken as strings, being converted if necessary; this conversion shall be as described in Expressions in awk, with the exception that the printf format in OFMT shall be used instead of the value in CONVFMT. An empty expression list shall stand for the whole input record ($0). The printf statement shall produce output based on a notation similar to the File Format Notation used to describe file formats in this volume of POSIX.12017 (see the Base Definitions volume of POSIX.12017, Chapter 5, File Format Notation). Output shall be produced as specified with the first expression argument as the string format and subsequent expression arguments as the strings arg1 to argn, inclusive, with the following exceptions: 1. The format shall be an actual character string rather than a graphical representation. Therefore, it cannot contain empty character positions. The <space> in the format string, in any context other than a flag of a conversion specification, shall be treated as an ordinary character that is copied to the output. 2. If the character set contains a '' character and that character appears in the format string, it shall be treated as an ordinary character that is copied to the output. 3. The escape sequences beginning with a <backslash> character shall be treated as sequences of ordinary characters that are copied to the output. Note that these same sequences shall be interpreted lexically by awk when they appear in literal strings, but they shall not be treated specially by the printf statement. 4. A field width or precision can be specified as the '*' character instead of a digit string. In this case the next argument from the expression list shall be fetched and its numeric value taken as the field width or precision. 5. The implementation shall not precede or follow output from the d or u conversion specifier characters with <blank> characters not specified by the format string. 6. The implementation shall not precede output from the o conversion specifier character with leading zeros not specified by the format string. 7. For the c conversion specifier character: if the argument has a numeric value, the character whose encoding is that value shall be output. If the value is zero or is not the encoding of any character in the character set, the behavior is undefined. If the argument does not have a numeric value, the first character of the string value shall be output; if the string does not contain any characters, the behavior is undefined. 8. For each conversion specification that consumes an argument, the next expression argument shall be evaluated. With the exception of the c conversion specifier character, the value shall be converted (according to the rules specified in Expressions in awk) to the appropriate type for the conversion specification. 9. If there are insufficient expression arguments to satisfy all the conversion specifications in the format string, the behavior is undefined. 10. If any character sequence in the format string begins with a '%' character, but does not form a valid conversion specification, the behavior is unspecified. Both print and printf can output at least {LINE_MAX} bytes. Functions The awk language has a variety of built-in functions: arithmetic, string, input/output, and general. Arithmetic Functions The arithmetic functions, except for int, shall be based on the ISO C standard (see Section 1.1.2, Concepts Derived from the ISO C Standard). The behavior is undefined in cases where the ISO C standard specifies that an error be returned or that the behavior is undefined. Although the grammar (see Grammar) permits built-in functions to appear with no arguments or parentheses, unless the argument or parentheses are indicated as optional in the following list (by displaying them within the "[]" brackets), such use is undefined. atan2(y,x) Return arctangent of y/x in radians in the range [-,]. cos(x) Return cosine of x, where x is in radians. sin(x) Return sine of x, where x is in radians. exp(x) Return the exponential function of x. log(x) Return the natural logarithm of x. sqrt(x) Return the square root of x. int(x) Return the argument truncated to an integer. Truncation shall be toward 0 when x>0. rand() Return a random number n, such that 0n<1. srand([expr]) Set the seed value for rand to expr or use the time of day if expr is omitted. The previous seed value shall be returned. String Functions The string functions in the following list shall be supported. Although the grammar (see Grammar) permits built-in functions to appear with no arguments or parentheses, unless the argument or parentheses are indicated as optional in the following list (by displaying them within the "[]" brackets), such use is undefined. gsub(ere, repl[, in]) Behave like sub (see below), except that it shall replace all occurrences of the regular expression (like the ed utility global substitute) in $0 or in the in argument, when specified. index(s, t) Return the position, in characters, numbering from 1, in string s where string t first occurs, or zero if it does not occur at all. length[([s])] Return the length, in characters, of its argument taken as a string, or of the whole record, $0, if there is no argument. match(s, ere) Return the position, in characters, numbering from 1, in string s where the extended regular expression ere occurs, or zero if it does not occur at all. RSTART shall be set to the starting position (which is the same as the returned value), zero if no match is found; RLENGTH shall be set to the length of the matched string, -1 if no match is found. split(s, a[, fs ]) Split the string s into array elements a[1], a[2], ..., a[n], and return n. All elements of the array shall be deleted before the split is performed. The separation shall be done with the ERE fs or with the field separator FS if fs is not given. Each array element shall have a string value when created and, if appropriate, the array element shall be considered a numeric string (see Expressions in awk). The effect of a null string as the value of fs is unspecified. sprintf(fmt, expr, expr, ...) Format the expressions according to the printf format given by fmt and return the resulting string. sub(ere, repl[, in ]) Substitute the string repl in place of the first instance of the extended regular expression ERE in string in and return the number of substitutions. An <ampersand> ('&') appearing in the string repl shall be replaced by the string from in that matches the ERE. An <ampersand> preceded with a <backslash> shall be interpreted as the literal <ampersand> character. An occurrence of two consecutive <backslash> characters shall be interpreted as just a single literal <backslash> character. Any other occurrence of a <backslash> (for example, preceding any other character) shall be treated as a literal <backslash> character. Note that if repl is a string literal (the lexical token STRING; see Grammar), the handling of the <ampersand> character occurs after any lexical processing, including any lexical <backslash>-escape sequence processing. If in is specified and it is not an lvalue (see Expressions in awk), the behavior is undefined. If in is omitted, awk shall use the current record ($0) in its place. substr(s, m[, n ]) Return the at most n-character substring of s that begins at position m, numbering from 1. If n is omitted, or if n specifies more characters than are left in the string, the length of the substring shall be limited by the length of the string s. tolower(s) Return a string based on the string s. Each character in s that is an uppercase letter specified to have a tolower mapping by the LC_CTYPE category of the current locale shall be replaced in the returned string by the lowercase letter specified by the mapping. Other characters in s shall be unchanged in the returned string. toupper(s) Return a string based on the string s. Each character in s that is a lowercase letter specified to have a toupper mapping by the LC_CTYPE category of the current locale is replaced in the returned string by the uppercase letter specified by the mapping. Other characters in s are unchanged in the returned string. All of the preceding functions that take ERE as a parameter expect a pattern or a string valued expression that is a regular expression as defined in Regular Expressions. Input/Output and General Functions The input/output and general functions are: close(expression) Close the file or pipe opened by a print or printf statement or a call to getline with the same string- valued expression. The limit on the number of open expression arguments is implementation-defined. If the close was successful, the function shall return zero; otherwise, it shall return non-zero. expression | getline [var] Read a record of input from a stream piped from the output of a command. The stream shall be created if no stream is currently open with the value of expression as its command name. The stream created shall be equivalent to one created by a call to the popen() function with the value of expression as the command argument and a value of r as the mode argument. As long as the stream remains open, subsequent calls in which expression evaluates to the same string value shall read subsequent records from the stream. The stream shall remain open until the close function is called with an expression that evaluates to the same string value. At that time, the stream shall be closed as if by a call to the pclose() function. If var is omitted, $0 and NF shall be set; otherwise, var shall be set and, if appropriate, it shall be considered a numeric string (see Expressions in awk). The getline operator can form ambiguous constructs when there are unparenthesized operators (including concatenate) to the left of the '|' (to the beginning of the expression containing getline). In the context of the '$' operator, '|' shall behave as if it had a lower precedence than '$'. The result of evaluating other operators is unspecified, and conforming applications shall parenthesize properly all such usages. getline Set $0 to the next input record from the current input file. This form of getline shall set the NF, NR, and FNR variables. getline var Set variable var to the next input record from the current input file and, if appropriate, var shall be considered a numeric string (see Expressions in awk). This form of getline shall set the FNR and NR variables. getline [var] < expression Read the next record of input from a named file. The expression shall be evaluated to produce a string that is used as a pathname. If the file of that name is not currently open, it shall be opened. As long as the stream remains open, subsequent calls in which expression evaluates to the same string value shall read subsequent records from the file. The file shall remain open until the close function is called with an expression that evaluates to the same string value. If var is omitted, $0 and NF shall be set; otherwise, var shall be set and, if appropriate, it shall be considered a numeric string (see Expressions in awk). The getline operator can form ambiguous constructs when there are unparenthesized binary operators (including concatenate) to the right of the '<' (up to the end of the expression containing the getline). The result of evaluating such a construct is unspecified, and conforming applications shall parenthesize properly all such usages. system(expression) Execute the command given by expression in a manner equivalent to the system() function defined in the System Interfaces volume of POSIX.12017 and return the exit status of the command. All forms of getline shall return 1 for successful input, zero for end-of-file, and -1 for an error. Where strings are used as the name of a file or pipeline, the application shall ensure that the strings are textually identical. The terminology ``same string value'' implies that ``equivalent strings'', even those that differ only by <space> characters, represent different files. User-Defined Functions The awk language also provides user-defined functions. Such functions can be defined as: function name([parameter, ...]) { statements } A function can be referred to anywhere in an awk program; in particular, its use can precede its definition. The scope of a function is global. Function parameters, if present, can be either scalars or arrays; the behavior is undefined if an array name is passed as a parameter that the function uses as a scalar, or if a scalar expression is passed as a parameter that the function uses as an array. Function parameters shall be passed by value if scalar and by reference if array name. The number of parameters in the function definition need not match the number of parameters in the function call. Excess formal parameters can be used as local variables. If fewer arguments are supplied in a function call than are in the function definition, the extra parameters that are used in the function body as scalars shall evaluate to the uninitialized value until they are otherwise initialized, and the extra parameters that are used in the function body as arrays shall be treated as uninitialized arrays where each element evaluates to the uninitialized value until otherwise initialized. When invoking a function, no white space can be placed between the function name and the opening parenthesis. Function calls can be nested and recursive calls can be made upon functions. Upon return from any nested or recursive function call, the values of all of the calling function's parameters shall be unchanged, except for array parameters passed by reference. The return statement can be used to return a value. If a return statement appears outside of a function definition, the behavior is undefined. In the function definition, <newline> characters shall be optional before the opening brace and after the closing brace. Function definitions can appear anywhere in the program where a pattern-action pair is allowed. Grammar The grammar in this section and the lexical conventions in the following section shall together describe the syntax for awk programs. The general conventions for this style of grammar are described in Section 1.3, Grammar Conventions. A valid program can be represented as the non-terminal symbol program in the grammar. This formal syntax shall take precedence over the preceding text syntax description. %token NAME NUMBER STRING ERE %token FUNC_NAME /* Name followed by '(' without white space. */ /* Keywords */ %token Begin End /* 'BEGIN' 'END' */ %token Break Continue Delete Do Else /* 'break' 'continue' 'delete' 'do' 'else' */ %token Exit For Function If In /* 'exit' 'for' 'function' 'if' 'in' */ %token Next Print Printf Return While /* 'next' 'print' 'printf' 'return' 'while' */ /* Reserved function names */ %token BUILTIN_FUNC_NAME /* One token for the following: * atan2 cos sin exp log sqrt int rand srand * gsub index length match split sprintf sub * substr tolower toupper close system */ %token GETLINE /* Syntactically different from other built-ins. */ /* Two-character tokens. */ %token ADD_ASSIGN SUB_ASSIGN MUL_ASSIGN DIV_ASSIGN MOD_ASSIGN POW_ASSIGN /* '+=' '-=' '*=' '/=' '%=' '^=' */ %token OR AND NO_MATCH EQ LE GE NE INCR DECR APPEND /* '||' '&&' '!~' '==' '<=' '>=' '!=' '++' '--' '>>' */ /* One-character tokens. */ %token '{' '}' '(' ')' '[' ']' ',' ';' NEWLINE %token '+' '-' '*' '%' '^' '!' '>' '<' '|' '?' ':' '~' '$' '=' %start program %% program : item_list | item_list item ; item_list : /* empty */ | item_list item terminator ; item : action | pattern action | normal_pattern | Function NAME '(' param_list_opt ')' newline_opt action | Function FUNC_NAME '(' param_list_opt ')' newline_opt action ; param_list_opt : /* empty */ | param_list ; param_list : NAME | param_list ',' NAME ; pattern : normal_pattern | special_pattern ; normal_pattern : expr | expr ',' newline_opt expr ; special_pattern : Begin | End ; action : '{' newline_opt '}' | '{' newline_opt terminated_statement_list '}' | '{' newline_opt unterminated_statement_list '}' ; terminator : terminator NEWLINE | ';' | NEWLINE ; terminated_statement_list : terminated_statement | terminated_statement_list terminated_statement ; unterminated_statement_list : unterminated_statement | terminated_statement_list unterminated_statement ; terminated_statement : action newline_opt | If '(' expr ')' newline_opt terminated_statement | If '(' expr ')' newline_opt terminated_statement Else newline_opt terminated_statement | While '(' expr ')' newline_opt terminated_statement | For '(' simple_statement_opt ';' expr_opt ';' simple_statement_opt ')' newline_opt terminated_statement | For '(' NAME In NAME ')' newline_opt terminated_statement | ';' newline_opt | terminatable_statement NEWLINE newline_opt | terminatable_statement ';' newline_opt ; unterminated_statement : terminatable_statement | If '(' expr ')' newline_opt unterminated_statement | If '(' expr ')' newline_opt terminated_statement Else newline_opt unterminated_statement | While '(' expr ')' newline_opt unterminated_statement | For '(' simple_statement_opt ';' expr_opt ';' simple_statement_opt ')' newline_opt unterminated_statement | For '(' NAME In NAME ')' newline_opt unterminated_statement ; terminatable_statement : simple_statement | Break | Continue | Next | Exit expr_opt | Return expr_opt | Do newline_opt terminated_statement While '(' expr ')' ; simple_statement_opt : /* empty */ | simple_statement ; simple_statement : Delete NAME '[' expr_list ']' | expr | print_statement ; print_statement : simple_print_statement | simple_print_statement output_redirection ; simple_print_statement : Print print_expr_list_opt | Print '(' multiple_expr_list ')' | Printf print_expr_list | Printf '(' multiple_expr_list ')' ; output_redirection : '>' expr | APPEND expr | '|' expr ; expr_list_opt : /* empty */ | expr_list ; expr_list : expr | multiple_expr_list ; multiple_expr_list : expr ',' newline_opt expr | multiple_expr_list ',' newline_opt expr ; expr_opt : /* empty */ | expr ; expr : unary_expr | non_unary_expr ; unary_expr : '+' expr | '-' expr | unary_expr '^' expr | unary_expr '*' expr | unary_expr '/' expr | unary_expr '%' expr | unary_expr '+' expr | unary_expr '-' expr | unary_expr non_unary_expr | unary_expr '<' expr | unary_expr LE expr | unary_expr NE expr | unary_expr EQ expr | unary_expr '>' expr | unary_expr GE expr | unary_expr '~' expr | unary_expr NO_MATCH expr | unary_expr In NAME | unary_expr AND newline_opt expr | unary_expr OR newline_opt expr | unary_expr '?' expr ':' expr | unary_input_function ; non_unary_expr : '(' expr ')' | '!' expr | non_unary_expr '^' expr | non_unary_expr '*' expr | non_unary_expr '/' expr | non_unary_expr '%' expr | non_unary_expr '+' expr | non_unary_expr '-' expr | non_unary_expr non_unary_expr | non_unary_expr '<' expr | non_unary_expr LE expr | non_unary_expr NE expr | non_unary_expr EQ expr | non_unary_expr '>' expr | non_unary_expr GE expr | non_unary_expr '~' expr | non_unary_expr NO_MATCH expr | non_unary_expr In NAME | '(' multiple_expr_list ')' In NAME | non_unary_expr AND newline_opt expr | non_unary_expr OR newline_opt expr | non_unary_expr '?' expr ':' expr | NUMBER | STRING | lvalue | ERE | lvalue INCR | lvalue DECR | INCR lvalue | DECR lvalue | lvalue POW_ASSIGN expr | lvalue MOD_ASSIGN expr | lvalue MUL_ASSIGN expr | lvalue DIV_ASSIGN expr | lvalue ADD_ASSIGN expr | lvalue SUB_ASSIGN expr | lvalue '=' expr | FUNC_NAME '(' expr_list_opt ')' /* no white space allowed before '(' */ | BUILTIN_FUNC_NAME '(' expr_list_opt ')' | BUILTIN_FUNC_NAME | non_unary_input_function ; print_expr_list_opt : /* empty */ | print_expr_list ; print_expr_list : print_expr | print_expr_list ',' newline_opt print_expr ; print_expr : unary_print_expr | non_unary_print_expr ; unary_print_expr : '+' print_expr | '-' print_expr | unary_print_expr '^' print_expr | unary_print_expr '*' print_expr | unary_print_expr '/' print_expr | unary_print_expr '%' print_expr | unary_print_expr '+' print_expr | unary_print_expr '-' print_expr | unary_print_expr non_unary_print_expr | unary_print_expr '~' print_expr | unary_print_expr NO_MATCH print_expr | unary_print_expr In NAME | unary_print_expr AND newline_opt print_expr | unary_print_expr OR newline_opt print_expr | unary_print_expr '?' print_expr ':' print_expr ; non_unary_print_expr : '(' expr ')' | '!' print_expr | non_unary_print_expr '^' print_expr | non_unary_print_expr '*' print_expr | non_unary_print_expr '/' print_expr | non_unary_print_expr '%' print_expr | non_unary_print_expr '+' print_expr | non_unary_print_expr '-' print_expr | non_unary_print_expr non_unary_print_expr | non_unary_print_expr '~' print_expr | non_unary_print_expr NO_MATCH print_expr | non_unary_print_expr In NAME | '(' multiple_expr_list ')' In NAME | non_unary_print_expr AND newline_opt print_expr | non_unary_print_expr OR newline_opt print_expr | non_unary_print_expr '?' print_expr ':' print_expr | NUMBER | STRING | lvalue | ERE | lvalue INCR | lvalue DECR | INCR lvalue | DECR lvalue | lvalue POW_ASSIGN print_expr | lvalue MOD_ASSIGN print_expr | lvalue MUL_ASSIGN print_expr | lvalue DIV_ASSIGN print_expr | lvalue ADD_ASSIGN print_expr | lvalue SUB_ASSIGN print_expr | lvalue '=' print_expr | FUNC_NAME '(' expr_list_opt ')' /* no white space allowed before '(' */ | BUILTIN_FUNC_NAME '(' expr_list_opt ')' | BUILTIN_FUNC_NAME ; lvalue : NAME | NAME '[' expr_list ']' | '$' expr ; non_unary_input_function : simple_get | simple_get '<' expr | non_unary_expr '|' simple_get ; unary_input_function : unary_expr '|' simple_get ; simple_get : GETLINE | GETLINE lvalue ; newline_opt : /* empty */ | newline_opt NEWLINE ; This grammar has several ambiguities that shall be resolved as follows: * Operator precedence and associativity shall be as described in Table 4-1, Expressions in Decreasing Precedence in awk. * In case of ambiguity, an else shall be associated with the most immediately preceding if that would satisfy the grammar. * In some contexts, a <slash> ('/') that is used to surround an ERE could also be the division operator. This shall be resolved in such a way that wherever the division operator could appear, a <slash> is assumed to be the division operator. (There is no unary division operator.) Each expression in an awk program shall conform to the precedence and associativity rules, even when this is not needed to resolve an ambiguity. For example, because '$' has higher precedence than '++', the string "$x++--" is not a valid awk expression, even though it is unambiguously parsed by the grammar as "$(x++)--". One convention that might not be obvious from the formal grammar is where <newline> characters are acceptable. There are several obvious placements such as terminating a statement, and a <backslash> can be used to escape <newline> characters between any lexical tokens. In addition, <newline> characters without <backslash> characters can follow a comma, an open brace, logical AND operator ("&&"), logical OR operator ("||"), the do keyword, the else keyword, and the closing parenthesis of an if, for, or while statement. For example: { print $1, $2 } Lexical Conventions The lexical conventions for awk programs, with respect to the preceding grammar, shall be as follows: 1. Except as noted, awk shall recognize the longest possible token or delimiter beginning at a given point. 2. A comment shall consist of any characters beginning with the <number-sign> character and terminated by, but excluding the next occurrence of, a <newline>. Comments shall have no effect, except to delimit lexical tokens. 3. The <newline> shall be recognized as the token NEWLINE. 4. A <backslash> character immediately followed by a <newline> shall have no effect. 5. The token STRING shall represent a string constant. A string constant shall begin with the character '"'. Within a string constant, a <backslash> character shall be considered to begin an escape sequence as specified in the table in the Base Definitions volume of POSIX.12017, Chapter 5, File Format Notation ('\\', '\a', '\b', '\f', '\n', '\r', '\t', '\v'). In addition, the escape sequences in Table 4-2, Escape Sequences in awk shall be recognized. A <newline> shall not occur within a string constant. A string constant shall be terminated by the first unescaped occurrence of the character '"' after the one that begins the string constant. The value of the string shall be the sequence of all unescaped characters and values of escape sequences between, but not including, the two delimiting '"' characters. 6. The token ERE represents an extended regular expression constant. An ERE constant shall begin with the <slash> character. Within an ERE constant, a <backslash> character shall be considered to begin an escape sequence as specified in the table in the Base Definitions volume of POSIX.12017, Chapter 5, File Format Notation. In addition, the escape sequences in Table 4-2, Escape Sequences in awk shall be recognized. The application shall ensure that a <newline> does not occur within an ERE constant. An ERE constant shall be terminated by the first unescaped occurrence of the <slash> character after the one that begins the ERE constant. The extended regular expression represented by the ERE constant shall be the sequence of all unescaped characters and values of escape sequences between, but not including, the two delimiting <slash> characters. 7. A <blank> shall have no effect, except to delimit lexical tokens or within STRING or ERE tokens. 8. The token NUMBER shall represent a numeric constant. Its form and numeric value shall either be equivalent to the decimal- floating-constant token as specified by the ISO C standard, or it shall be a sequence of decimal digits and shall be evaluated as an integer constant in decimal. In addition, implementations may accept numeric constants with the form and numeric value equivalent to the hexadecimal-constant and hexadecimal-floating-constant tokens as specified by the ISO C standard. If the value is too large or too small to be representable (see Section 1.1.2, Concepts Derived from the ISO C Standard), the behavior is undefined. 9. A sequence of underscores, digits, and alphabetics from the portable character set (see the Base Definitions volume of POSIX.12017, Section 6.1, Portable Character Set), beginning with an <underscore> or alphabetic character, shall be considered a word. 10. The following words are keywords that shall be recognized as individual tokens; the name of the token is the same as the keyword: BEGIN delete END function in printf break do exit getline next return continue else for if print while 11. The following words are names of built-in functions and shall be recognized as the token BUILTIN_FUNC_NAME: atan2 gsub log split sub toupper close index match sprintf substr cos int rand sqrt system exp length sin srand tolower The above-listed keywords and names of built-in functions are considered reserved words. 12. The token NAME shall consist of a word that is not a keyword or a name of a built-in function and is not followed immediately (without any delimiters) by the '(' character. 13. The token FUNC_NAME shall consist of a word that is not a keyword or a name of a built-in function, followed immediately (without any delimiters) by the '(' character. The '(' character shall not be included as part of the token. 14. The following two-character sequences shall be recognized as the named tokens: Token Name Sequence Token Name Sequence ADD_ASSIGN += NO_MATCH !~ SUB_ASSIGN -= EQ == MUL_ASSIGN *= LE <= DIV_ASSIGN /= GE >= MOD_ASSIGN %= NE != POW_ASSIGN ^= INCR ++ OR || DECR -- AND && APPEND >> 15. The following single characters shall be recognized as tokens whose names are the character: <newline> { } ( ) [ ] , ; + - * % ^ ! > < | ? : ~ $ = There is a lexical ambiguity between the token ERE and the tokens '/' and DIV_ASSIGN. When an input sequence begins with a <slash> character in any syntactic context where the token '/' or DIV_ASSIGN could appear as the next token in a valid program, the longer of those two tokens that can be recognized shall be recognized. In any other syntactic context where the token ERE could appear as the next token in a valid program, the token ERE shall be recognized. EXIT STATUS top The following exit values shall be returned: 0 All input files were processed successfully. >0 An error occurred. The exit status can be altered within the program by using an exit expression. CONSEQUENCES OF ERRORS top If any file operand is specified and the named file cannot be accessed, awk shall write a diagnostic message to standard error and terminate without any further action. If the program specified by either the program operand or a progfile operand is not a valid awk program (as specified in the EXTENDED DESCRIPTION section), the behavior is undefined. The following sections are informative. APPLICATION USAGE top The index, length, match, and substr functions should not be confused with similar functions in the ISO C standard; the awk versions deal with characters, while the ISO C standard deals with bytes. Because the concatenation operation is represented by adjacent expressions rather than an explicit operator, it is often necessary to use parentheses to enforce the proper evaluation precedence. When using awk to process pathnames, it is recommended that LC_ALL, or at least LC_CTYPE and LC_COLLATE, are set to POSIX or C in the environment, since pathnames can contain byte sequences that do not form valid characters in some locales, in which case the utility's behavior would be undefined. In the POSIX locale each byte is a valid single-byte character, and therefore this problem is avoided. On implementations where the "==" operator checks if strings collate equally, applications needing to check whether strings are identical can use: length(a) == length(b) && index(a,b) == 1 On implementations where the "==" operator checks if strings are identical, applications needing to check whether strings collate equally can use: a <= b && a >= b EXAMPLES top The awk program specified in the command line is most easily specified within single-quotes (for example, 'program') for applications using sh, because awk programs commonly contain characters that are special to the shell, including double- quotes. In the cases where an awk program contains single-quote characters, it is usually easiest to specify most of the program as strings within single-quotes concatenated by the shell with quoted single-quote characters. For example: awk '/'\''/ { print "quote:", $0 }' prints all lines from the standard input containing a single- quote character, prefixed with quote:. The following are examples of simple awk programs: 1. Write to the standard output all input lines for which field 3 is greater than 5: $3 > 5 2. Write every tenth line: (NR % 10) == 0 3. Write any line with a substring matching the regular expression: /(G|D)(2[0-9][[:alpha:]]*)/ 4. Print any line with a substring containing a 'G' or 'D', followed by a sequence of digits and characters. This example uses character classes digit and alpha to match language- independent digit and alphabetic characters respectively: /(G|D)([[:digit:][:alpha:]]*)/ 5. Write any line in which the second field matches the regular expression and the fourth field does not: $2 ~ /xyz/ && $4 !~ /xyz/ 6. Write any line in which the second field contains a <backslash>: $2 ~ /\\/ 7. Write any line in which the second field contains a <backslash>. Note that <backslash>-escapes are interpreted twice; once in lexical processing of the string and once in processing the regular expression: $2 ~ "\\\\" 8. Write the second to the last and the last field in each line. Separate the fields by a <colon>: {OFS=":";print $(NF-1), $NF} 9. Write the line number and number of fields in each line. The three strings representing the line number, the <colon>, and the number of fields are concatenated and that string is written to standard output: {print NR ":" NF} 10. Write lines longer than 72 characters: length($0) > 72 11. Write the first two fields in opposite order separated by OFS: { print $2, $1 } 12. Same, with input fields separated by a <comma> or <space> and <tab> characters, or both: BEGIN { FS = ",[ \t]*|[ \t]+" } { print $2, $1 } 13. Add up the first column, print sum, and average: {s += $1 } END {print "sum is ", s, " average is", s/NR} 14. Write fields in reverse order, one per line (many lines out for each line in): { for (i = NF; i > 0; --i) print $i } 15. Write all lines between occurrences of the strings start and stop: /start/, /stop/ 16. Write all lines whose first field is different from the previous one: $1 != prev { print; prev = $1 } 17. Simulate echo: BEGIN { for (i = 1; i < ARGC; ++i) printf("%s%s", ARGV[i], i==ARGC-1?"\n":" ") } 18. Write the path prefixes contained in the PATH environment variable, one per line: BEGIN { n = split (ENVIRON["PATH"], path, ":") for (i = 1; i <= n; ++i) print path[i] } 19. If there is a file named input containing page headers of the form: Page # and a file named program that contains: /Page/ { $2 = n++; } { print } then the command line: awk -f program n=5 input prints the file input, filling in page numbers starting at 5. RATIONALE top This description is based on the new awk, ``nawk'', (see the referenced The AWK Programming Language), which introduced a number of new features to the historical awk: 1. New keywords: delete, do, function, return 2. New built-in functions: atan2, close, cos, gsub, match, rand, sin, srand, sub, system 3. New predefined variables: FNR, ARGC, ARGV, RSTART, RLENGTH, SUBSEP 4. New expression operators: ?, :, ,, ^ 5. The FS variable and the third argument to split, now treated as extended regular expressions. 6. The operator precedence, changed to more closely match the C language. Two examples of code that operate differently are: while ( n /= 10 > 1) ... if (!"wk" ~ /bwk/) ... Several features have been added based on newer implementations of awk: * Multiple instances of -f progfile are permitted. * The new option -v assignment. * The new predefined variable ENVIRON. * New built-in functions toupper and tolower. * More formatting capabilities are added to printf to match the ISO C standard. Earlier versions of this standard required implementations to support multiple adjacent <semicolon>s, lines with one or more <semicolon> before a rule (pattern-action pairs), and lines with only <semicolon>(s). These are not required by this standard and are considered poor programming practice, but can be accepted by an implementation of awk as an extension. The overall awk syntax has always been based on the C language, with a few features from the shell command language and other sources. Because of this, it is not completely compatible with any other language, which has caused confusion for some users. It is not the intent of the standard developers to address such issues. A few relatively minor changes toward making the language more compatible with the ISO C standard were made; most of these changes are based on similar changes in recent implementations, as described above. There remain several C-language conventions that are not in awk. One of the notable ones is the <comma> operator, which is commonly used to specify multiple expressions in the C language for statement. Also, there are various places where awk is more restrictive than the C language regarding the type of expression that can be used in a given context. These limitations are due to the different features that the awk language does provide. Regular expressions in awk have been extended somewhat from historical implementations to make them a pure superset of extended regular expressions, as defined by POSIX.12008 (see the Base Definitions volume of POSIX.12017, Section 9.4, Extended Regular Expressions). The main extensions are internationalization features and interval expressions. Historical implementations of awk have long supported <backslash>-escape sequences as an extension to extended regular expressions, and this extension has been retained despite inconsistency with other utilities. The number of escape sequences recognized in both extended regular expressions and strings has varied (generally increasing with time) among implementations. The set specified by POSIX.12008 includes most sequences known to be supported by popular implementations and by the ISO C standard. One sequence that is not supported is hexadecimal value escapes beginning with '\x'. This would allow values expressed in more than 9 bits to be used within awk as in the ISO C standard. However, because this syntax has a non- deterministic length, it does not permit the subsequent character to be a hexadecimal digit. This limitation can be dealt with in the C language by the use of lexical string concatenation. In the awk language, concatenation could also be a solution for strings, but not for extended regular expressions (either lexical ERE tokens or strings used dynamically as regular expressions). Because of this limitation, the feature has not been added to POSIX.12008. When a string variable is used in a context where an extended regular expression normally appears (where the lexical token ERE is used in the grammar) the string does not contain the literal <slash> characters. Some versions of awk allow the form: func name(args, ... ) { statements } This has been deprecated by the authors of the language, who asked that it not be specified. Historical implementations of awk produce an error if a next statement is executed in a BEGIN action, and cause awk to terminate if a next statement is executed in an END action. This behavior has not been documented, and it was not believed that it was necessary to standardize it. The specification of conversions between string and numeric values is much more detailed than in the documentation of historical implementations or in the referenced The AWK Programming Language. Although most of the behavior is designed to be intuitive, the details are necessary to ensure compatible behavior from different implementations. This is especially important in relational expressions since the types of the operands determine whether a string or numeric comparison is performed. From the perspective of an application developer, it is usually sufficient to expect intuitive behavior and to force conversions (by adding zero or concatenating a null string) when the type of an expression does not obviously match what is needed. The intent has been to specify historical practice in almost all cases. The one exception is that, in historical implementations, variables and constants maintain both string and numeric values after their original value is converted by any use. This means that referencing a variable or constant can have unexpected side-effects. For example, with historical implementations the following program: { a = "+2" b = 2 if (NR % 2) c = a + b if (a == b) print "numeric comparison" else print "string comparison" } would perform a numeric comparison (and output numeric comparison) for each odd-numbered line, but perform a string comparison (and output string comparison) for each even-numbered line. POSIX.12008 ensures that comparisons will be numeric if necessary. With historical implementations, the following program: BEGIN { OFMT = "%e" print 3.14 OFMT = "%f" print 3.14 } would output "3.140000e+00" twice, because in the second print statement the constant "3.14" would have a string value from the previous conversion. POSIX.12008 requires that the output of the second print statement be "3.140000". The behavior of historical implementations was seen as too unintuitive and unpredictable. It was pointed out that with the rules contained in early drafts, the following script would print nothing: BEGIN { y[1.5] = 1 OFMT = "%e" print y[1.5] } Therefore, a new variable, CONVFMT, was introduced. The OFMT variable is now restricted to affecting output conversions of numbers to strings and CONVFMT is used for internal conversions, such as comparisons or array indexing. The default value is the same as that for OFMT, so unless a program changes CONVFMT (which no historical program would do), it will receive the historical behavior associated with internal string conversions. The POSIX awk lexical and syntactic conventions are specified more formally than in other sources. Again the intent has been to specify historical practice. One convention that may not be obvious from the formal grammar as in other verbal descriptions is where <newline> characters are acceptable. There are several obvious placements such as terminating a statement, and a <backslash> can be used to escape <newline> characters between any lexical tokens. In addition, <newline> characters without <backslash> characters can follow a comma, an open brace, a logical AND operator ("&&"), a logical OR operator ("||"), the do keyword, the else keyword, and the closing parenthesis of an if, for, or while statement. For example: { print $1, $2 } The requirement that awk add a trailing <newline> to the program argument text is to simplify the grammar, making it match a text file in form. There is no way for an application or test suite to determine whether a literal <newline> is added or whether awk simply acts as if it did. POSIX.12008 requires several changes from historical implementations in order to support internationalization. Probably the most subtle of these is the use of the decimal-point character, defined by the LC_NUMERIC category of the locale, in representations of floating-point numbers. This locale-specific character is used in recognizing numeric input, in converting between strings and numeric values, and in formatting output. However, regardless of locale, the <period> character (the decimal-point character of the POSIX locale) is the decimal-point character recognized in processing awk programs (including assignments in command line arguments). This is essentially the same convention as the one used in the ISO C standard. The difference is that the C language includes the setlocale() function, which permits an application to modify its locale. Because of this capability, a C application begins executing with its locale set to the C locale, and only executes in the environment-specified locale after an explicit call to setlocale(). However, adding such an elaborate new feature to the awk language was seen as inappropriate for POSIX.12008. It is possible to execute an awk program explicitly in any desired locale by setting the environment in the shell. The undefined behavior resulting from NULs in extended regular expressions allows future extensions for the GNU gawk program to process binary data. The behavior in the case of invalid awk programs (including lexical, syntactic, and semantic errors) is undefined because it was considered overly limiting on implementations to specify. In most cases such errors can be expected to produce a diagnostic and a non-zero exit status. However, some implementations may choose to extend the language in ways that make use of certain invalid constructs. Other invalid constructs might be deemed worthy of a warning, but otherwise cause some reasonable behavior. Still other constructs may be very difficult to detect in some implementations. Also, different implementations might detect a given error during an initial parsing of the program (before reading any input files) while others might detect it when executing the program after reading some input. Implementors should be aware that diagnosing errors as early as possible and producing useful diagnostics can ease debugging of applications, and thus make an implementation more usable. The unspecified behavior from using multi-character RS values is to allow possible future extensions based on extended regular expressions used for record separators. Historical implementations take the first character of the string and ignore the others. Unspecified behavior when split(string,array,<null>) is used is to allow a proposed future extension that would split up a string into an array of individual characters. In the context of the getline function, equally good arguments for different precedences of the | and < operators can be made. Historical practice has been that: getline < "a" "b" is parsed as: ( getline < "a" ) "b" although many would argue that the intent was that the file ab should be read. However: getline < "x" + 1 parses as: getline < ( "x" + 1 ) Similar problems occur with the | version of getline, particularly in combination with $. For example: $"echo hi" | getline (This situation is particularly problematic when used in a print statement, where the |getline part might be a redirection of the print.) Since in most cases such constructs are not (or at least should not) be used (because they have a natural ambiguity for which there is no conventional parsing), the meaning of these constructs has been made explicitly unspecified. (The effect is that a conforming application that runs into the problem must parenthesize to resolve the ambiguity.) There appeared to be few if any actual uses of such constructs. Grammars can be written that would cause an error under these circumstances. Where backwards-compatibility is not a large consideration, implementors may wish to use such grammars. Some historical implementations have allowed some built-in functions to be called without an argument list, the result being a default argument list chosen in some ``reasonable'' way. Use of length as a synonym for length($0) is the only one of these forms that is thought to be widely known or widely used; this particular form is documented in various places (for example, most historical awk reference pages, although not in the referenced The AWK Programming Language) as legitimate practice. With this exception, default argument lists have always been undocumented and vaguely defined, and it is not at all clear how (or if) they should be generalized to user-defined functions. They add no useful functionality and preclude possible future extensions that might need to name functions without calling them. Not standardizing them seems the simplest course. The standard developers considered that length merited special treatment, however, since it has been documented in the past and sees possibly substantial use in historical programs. Accordingly, this usage has been made legitimate, but Issue 5 removed the obsolescent marking for XSI-conforming implementations and many otherwise conforming applications depend on this feature. In sub and gsub, if repl is a string literal (the lexical token STRING), then two consecutive <backslash> characters should be used in the string to ensure a single <backslash> will precede the <ampersand> when the resultant string is passed to the function. (For example, to specify one literal <ampersand> in the replacement string, use gsub(ERE, "\\&").) Historically, the only special character in the repl argument of sub and gsub string functions was the <ampersand> ('&') character and preceding it with the <backslash> character was used to turn off its special meaning. The description in the ISO POSIX2:1993 standard introduced behavior such that the <backslash> character was another special character and it was unspecified whether there were any other special characters. This description introduced several portability problems, some of which are described below, and so it has been replaced with the more historical description. Some of the problems include: * Historically, to create the replacement string, a script could use gsub(ERE, "\\&"), but with the ISO POSIX2:1993 standard wording, it was necessary to use gsub(ERE, "\\\\&"). The <backslash> characters are doubled here because all string literals are subject to lexical analysis, which would reduce each pair of <backslash> characters to a single <backslash> before being passed to gsub. * Since it was unspecified what the special characters were, for portable scripts to guarantee that characters are printed literally, each character had to be preceded with a <backslash>. (For example, a portable script had to use gsub(ERE, "\\h\\i") to produce a replacement string of "hi".) The description for comparisons in the ISO POSIX2:1993 standard did not properly describe historical practice because of the way numeric strings are compared as numbers. The current rules cause the following code: if (0 == "000") print "strange, but true" else print "not true" to do a numeric comparison, causing the if to succeed. It should be intuitively obvious that this is incorrect behavior, and indeed, no historical implementation of awk actually behaves this way. To fix this problem, the definition of numeric string was enhanced to include only those values obtained from specific circumstances (mostly external sources) where it is not possible to determine unambiguously whether the value is intended to be a string or a numeric. Variables that are assigned to a numeric string shall also be treated as a numeric string. (For example, the notion of a numeric string can be propagated across assignments.) In comparisons, all variables having the uninitialized value are to be treated as a numeric operand evaluating to the numeric value zero. Uninitialized variables include all types of variables including scalars, array elements, and fields. The definition of an uninitialized value in Variables and Special Variables is necessary to describe the value placed on uninitialized variables and on fields that are valid (for example, < $NF) but have no characters in them and to describe how these variables are to be used in comparisons. A valid field, such as $1, that has no characters in it can be obtained from an input line of "\t\t" when FS='\t'. Historically, the comparison ($1<10) was done numerically after evaluating $1 to the value zero. The phrase ``... also shall have the numeric value of the numeric string'' was removed from several sections of the ISO POSIX2:1993 standard because is specifies an unnecessary implementation detail. It is not necessary for POSIX.12008 to specify that these objects be assigned two different values. It is only necessary to specify that these objects may evaluate to two different values depending on context. Historical implementations of awk did not parse hexadecimal integer or floating constants like "0xa" and "0xap0". Due to an oversight, the 2001 through 2004 editions of this standard required support for hexadecimal floating constants. This was due to the reference to atof(). This version of the standard allows but does not require implementations to use atof() and includes a description of how floating-point numbers are recognized as an alternative to match historic behavior. The intent of this change is to allow implementations to recognize floating-point constants according to either the ISO/IEC 9899:1990 standard or ISO/IEC 9899:1999 standard, and to allow (but not require) implementations to recognize hexadecimal integer constants. Historical implementations of awk did not support floating-point infinities and NaNs in numeric strings; e.g., "-INF" and "NaN". However, implementations that use the atof() or strtod() functions to do the conversion picked up support for these values if they used a ISO/IEC 9899:1999 standard version of the function instead of a ISO/IEC 9899:1990 standard version. Due to an oversight, the 2001 through 2004 editions of this standard did not allow support for infinities and NaNs, but in this revision support is allowed (but not required). This is a silent change to the behavior of awk programs; for example, in the POSIX locale the expression: ("-INF" + 0 < 0) formerly had the value 0 because "-INF" converted to 0, but now it may have the value 0 or 1. FUTURE DIRECTIONS top A future version of this standard may require the "!=" and "==" operators to perform string comparisons by checking if the strings are identical (and not by checking if they collate equally). SEE ALSO top Section 1.3, Grammar Conventions, grep(1p), lex(1p), sed(1p) The Base Definitions volume of POSIX.12017, Chapter 5, File Format Notation, Section 6.1, Portable Character Set, Chapter 8, Environment Variables, Chapter 9, Regular Expressions, Section 12.2, Utility Syntax Guidelines The System Interfaces volume of POSIX.12017, atof(3p), exec(1p), isspace(3p), popen(3p), setlocale(3p), strtod(3p) COPYRIGHT top Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html . Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html . IEEE/The Open Group 2017 AWK(1P) Pages that refer to this page: bc(1p), colrm(1), join(1p), printf(1p), sed(1p) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. zcat(1p) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training zcat(1p) Linux manual page PROLOG | NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | STDIN | INPUT FILES | ENVIRONMENT VARIABLES | ASYNCHRONOUS EVENTS | STDOUT | STDERR | OUTPUT FILES | EXTENDED DESCRIPTION | EXIT STATUS | CONSEQUENCES OF ERRORS | APPLICATION USAGE | EXAMPLES | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT ZCAT(1P) POSIX Programmer's Manual ZCAT(1P) PROLOG top This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux. NAME top zcat expand and concatenate data SYNOPSIS top zcat [file...] DESCRIPTION top The zcat utility shall write to standard output the uncompressed form of files that have been compressed using the compress utility. It is the equivalent of uncompress -c. Input files are not affected. OPTIONS top None. OPERANDS top The following operand shall be supported: file The pathname of a file previously processed by the compress utility. If file already has the .Z suffix specified, it is used as submitted. Otherwise, the .Z suffix is appended to the filename prior to processing. STDIN top The standard input shall be used only if no file operands are specified, or if a file operand is '-'. INPUT FILES top Input files shall be compressed files that are in the format produced by the compress utility. ENVIRONMENT VARIABLES top The following environment variables shall affect the execution of zcat: LANG Provide a default value for the internationalization variables that are unset or null. (See the Base Definitions volume of POSIX.12017, Section 8.2, Internationalization Variables for the precedence of internationalization variables used to determine the values of locale categories.) LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_CTYPE Determine the locale for the interpretation of sequences of bytes of text data as characters (for example, single-byte as opposed to multi-byte characters in arguments). LC_MESSAGES Determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error. NLSPATH Determine the location of message catalogs for the processing of LC_MESSAGES. ASYNCHRONOUS EVENTS top Default. STDOUT top The compressed files given as input shall be written on standard output in their uncompressed form. STDERR top The standard error shall be used only for diagnostic messages. OUTPUT FILES top None. EXTENDED DESCRIPTION top None. EXIT STATUS top The following exit values shall be returned: 0 Successful completion. >0 An error occurred. CONSEQUENCES OF ERRORS top Default. The following sections are informative. APPLICATION USAGE top None. EXAMPLES top None. RATIONALE top None. FUTURE DIRECTIONS top None. SEE ALSO top compress(1p), uncompress(1p) The Base Definitions volume of POSIX.12017, Chapter 8, Environment Variables COPYRIGHT top Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html . Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html . IEEE/The Open Group 2017 ZCAT(1P) Pages that refer to this page: compress(1p), uncompress(1p) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Decompress "file2.txt" and "file1.txt" and print lines in "file1.txt" that match the 5th tab separated field in "file2.txt" Bash Command:<START>awk -F'\t' 'NR==FNR{a[$5];next} $5 in a' <(zcat file2.txt) <(zcat file1.txt)<END>

Decompress "path/to/test/file.gz" to standard output and save all lines matching "my regex" and not matching "other regex" to files with a 1000000 line limit

gzip -dc path/to/test/file.gz | grep -P 'my regex' | grep -vP 'other regex' | split -dl1000000 - file

['split', 'grep', 'file']

Output a Bash command to accomplish the following task. Task: Decompress "path/to/test/file.gz" to standard output and save all lines matching "my regex" and not matching "other regex" to files with a 1000000 line limit Bash Command:<START>gzip -dc path/to/test/file.gz | grep -P 'my regex' | grep -vP 'other regex' | split -dl1000000 - file<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # split\n\n> Split a file into pieces.\n> More information: <https://www.gnu.org/software/coreutils/split>.\n\n- Split a file, each split having 10 lines (except the last split):\n\n`split -l {{10}} {{path/to/file}}`\n\n- Split a file into 5 files. File is split such that each split has same size (except the last split):\n\n`split -n {{5}} {{path/to/file}}`\n\n- Split a file with 512 bytes in each split (except the last split; use 512k for kilobytes and 512m for megabytes):\n\n`split -b {{512}} {{path/to/file}}`\n\n- Split a file with at most 512 bytes in each split without breaking lines:\n\n`split -C {{512}} {{path/to/file}}`\n # grep\n\n> Find patterns in files using regular expressions.\n> More information: <https://www.gnu.org/software/grep/manual/grep.html>.\n\n- Search for a pattern within a file:\n\n`grep "{{search_pattern}}" {{path/to/file}}`\n\n- Search for an exact string (disables regular expressions):\n\n`grep --fixed-strings "{{exact_string}}" {{path/to/file}}`\n\n- Search for a pattern in all files recursively in a directory, showing line numbers of matches, ignoring binary files:\n\n`grep --recursive --line-number --binary-files={{without-match}} "{{search_pattern}}" {{path/to/directory}}`\n\n- Use extended regular expressions (supports `?`, `+`, `{}`, `()` and `|`), in case-insensitive mode:\n\n`grep --extended-regexp --ignore-case "{{search_pattern}}" {{path/to/file}}`\n\n- Print 3 lines of context around, before, or after each match:\n\n`grep --{{context|before-context|after-context}}={{3}} "{{search_pattern}}" {{path/to/file}}`\n\n- Print file name and line number for each match with color output:\n\n`grep --with-filename --line-number --color=always "{{search_pattern}}" {{path/to/file}}`\n\n- Search for lines matching a pattern, printing only the matched text:\n\n`grep --only-matching "{{search_pattern}}" {{path/to/file}}`\n\n- Search `stdin` for lines that do not match a pattern:\n\n`cat {{path/to/file}} | grep --invert-match "{{search_pattern}}"`\n # file\n\n> Determine file type.\n> More information: <https://manned.org/file>.\n\n- Give a description of the type of the specified file. Works fine for files with no file extension:\n\n`file {{path/to/file}}`\n\n- Look inside a zipped file and determine the file type(s) inside:\n\n`file -z {{foo.zip}}`\n\n- Allow file to work with special or device files:\n\n`file -s {{path/to/file}}`\n\n- Don't stop at first file type match; keep going until the end of the file:\n\n`file -k {{path/to/file}}`\n\n- Determine the MIME encoding type of a file:\n\n`file -i {{path/to/file}}`\n Task: Decompress "path/to/test/file.gz" to standard output and save all lines matching "my regex" and not matching "other regex" to files with a 1000000 line limit Bash Command:<START>gzip -dc path/to/test/file.gz | grep -P 'my regex' | grep -vP 'other regex' | split -dl1000000 - file<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: split(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training split(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON SPLIT(1) User Commands SPLIT(1) NAME top split - split a file into pieces SYNOPSIS top split [OPTION]... [FILE [PREFIX]] DESCRIPTION top Output pieces of FILE to PREFIXaa, PREFIXab, ...; default size is 1000 lines, and default PREFIX is 'x'. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -a, --suffix-length=N generate suffixes of length N (default 2) --additional-suffix=SUFFIX append an additional SUFFIX to file names -b, --bytes=SIZE put SIZE bytes per output file -C, --line-bytes=SIZE put at most SIZE bytes of records per output file -d use numeric suffixes starting at 0, not alphabetic --numeric-suffixes[=FROM] same as -d, but allow setting the start value -x use hex suffixes starting at 0, not alphabetic --hex-suffixes[=FROM] same as -x, but allow setting the start value -e, --elide-empty-files do not generate empty output files with '-n' --filter=COMMAND write to shell COMMAND; file name is $FILE -l, --lines=NUMBER put NUMBER lines/records per output file -n, --number=CHUNKS generate CHUNKS output files; see explanation below -t, --separator=SEP use SEP instead of newline as the record separator; '\0' (zero) specifies the NUL character -u, --unbuffered immediately copy input to output with '-n r/...' --verbose print a diagnostic just before each output file is opened --help display this help and exit --version output version information and exit The SIZE argument is an integer and optional unit (example: 10K is 10*1024). Units are K,M,G,T,P,E,Z,Y,R,Q (powers of 1024) or KB,MB,... (powers of 1000). Binary prefixes can be used, too: KiB=K, MiB=M, and so on. CHUNKS may be: N split into N files based on size of input K/N output Kth of N to stdout l/N split into N files without splitting lines/records l/K/N output Kth of N to stdout without splitting lines/records r/N like 'l' but use round robin distribution r/K/N likewise but only output Kth of N to stdout AUTHOR top Written by Torbjorn Granlund and Richard M. Stallman. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top Full documentation <https://www.gnu.org/software/coreutils/split> or available locally via: info '(coreutils) split invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 SPLIT(1) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. grep(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training grep(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | REGULAR EXPRESSIONS | EXIT STATUS | ENVIRONMENT | NOTES | COPYRIGHT | BUGS | EXAMPLE | SEE ALSO | COLOPHON GREP(1) User Commands GREP(1) NAME top grep - print lines that match patterns SYNOPSIS top grep [OPTION...] PATTERNS [FILE...] grep [OPTION...] -e PATTERNS ... [FILE...] grep [OPTION...] -f PATTERN_FILE ... [FILE...] DESCRIPTION top grep searches for PATTERNS in each FILE. PATTERNS is one or more patterns separated by newline characters, and grep prints each line that matches a pattern. Typically PATTERNS should be quoted when grep is used in a shell command. A FILE of - stands for standard input. If no FILE is given, recursive searches examine the working directory, and nonrecursive searches read standard input. OPTIONS top Generic Program Information --help Output a usage message and exit. -V, --version Output the version number of grep and exit. Pattern Syntax -E, --extended-regexp Interpret PATTERNS as extended regular expressions (EREs, see below). -F, --fixed-strings Interpret PATTERNS as fixed strings, not regular expressions. -G, --basic-regexp Interpret PATTERNS as basic regular expressions (BREs, see below). This is the default. -P, --perl-regexp Interpret PATTERNS as Perl-compatible regular expressions (PCREs). This option is experimental when combined with the -z (--null-data) option, and grep -P may warn of unimplemented features. Matching Control -e PATTERNS, --regexp=PATTERNS Use PATTERNS as the patterns. If this option is used multiple times or is combined with the -f (--file) option, search for all patterns given. This option can be used to protect a pattern beginning with -. -f FILE, --file=FILE Obtain patterns from FILE, one per line. If this option is used multiple times or is combined with the -e (--regexp) option, search for all patterns given. The empty file contains zero patterns, and therefore matches nothing. If FILE is - , read patterns from standard input. -i, --ignore-case Ignore case distinctions in patterns and input data, so that characters that differ only in case match each other. --no-ignore-case Do not ignore case distinctions in patterns and input data. This is the default. This option is useful for passing to shell scripts that already use -i, to cancel its effects because the two options override each other. -v, --invert-match Invert the sense of matching, to select non-matching lines. -w, --word-regexp Select only those lines containing matches that form whole words. The test is that the matching substring must either be at the beginning of the line, or preceded by a non-word constituent character. Similarly, it must be either at the end of the line or followed by a non-word constituent character. Word-constituent characters are letters, digits, and the underscore. This option has no effect if -x is also specified. -x, --line-regexp Select only those matches that exactly match the whole line. For a regular expression pattern, this is like parenthesizing the pattern and then surrounding it with ^ and $. General Output Control -c, --count Suppress normal output; instead print a count of matching lines for each input file. With the -v, --invert-match option (see above), count non-matching lines. --color[=WHEN], --colour[=WHEN] Surround the matched (non-empty) strings, matching lines, context lines, file names, line numbers, byte offsets, and separators (for fields and groups of context lines) with escape sequences to display them in color on the terminal. The colors are defined by the environment variable GREP_COLORS. WHEN is never, always, or auto. -L, --files-without-match Suppress normal output; instead print the name of each input file from which no output would normally have been printed. -l, --files-with-matches Suppress normal output; instead print the name of each input file from which output would normally have been printed. Scanning each input file stops upon first match. -m NUM, --max-count=NUM Stop reading a file after NUM matching lines. If NUM is zero, grep stops right away without reading input. A NUM of -1 is treated as infinity and grep does not stop; this is the default. If the input is standard input from a regular file, and NUM matching lines are output, grep ensures that the standard input is positioned to just after the last matching line before exiting, regardless of the presence of trailing context lines. This enables a calling process to resume a search. When grep stops after NUM matching lines, it outputs any trailing context lines. When the -c or --count option is also used, grep does not output a count greater than NUM. When the -v or --invert-match option is also used, grep stops after outputting NUM non-matching lines. -o, --only-matching Print only the matched (non-empty) parts of a matching line, with each such part on a separate output line. -q, --quiet, --silent Quiet; do not write anything to standard output. Exit immediately with zero status if any match is found, even if an error was detected. Also see the -s or --no-messages option. -s, --no-messages Suppress error messages about nonexistent or unreadable files. Output Line Prefix Control -b, --byte-offset Print the 0-based byte offset within the input file before each line of output. If -o (--only-matching) is specified, print the offset of the matching part itself. -H, --with-filename Print the file name for each match. This is the default when there is more than one file to search. This is a GNU extension. -h, --no-filename Suppress the prefixing of file names on output. This is the default when there is only one file (or only standard input) to search. --label=LABEL Display input actually coming from standard input as input coming from file LABEL. This can be useful for commands that transform a file's contents before searching, e.g., gzip -cd foo.gz | grep --label=foo -H 'some pattern'. See also the -H option. -n, --line-number Prefix each line of output with the 1-based line number within its input file. -T, --initial-tab Make sure that the first character of actual line content lies on a tab stop, so that the alignment of tabs looks normal. This is useful with options that prefix their output to the actual content: -H,-n, and -b. In order to improve the probability that lines from a single file will all start at the same column, this also causes the line number and byte offset (if present) to be printed in a minimum size field width. -Z, --null Output a zero byte (the ASCII NUL character) instead of the character that normally follows a file name. For example, grep -lZ outputs a zero byte after each file name instead of the usual newline. This option makes the output unambiguous, even in the presence of file names containing unusual characters like newlines. This option can be used with commands like find -print0, perl -0, sort -z, and xargs -0 to process arbitrary file names, even those that contain newline characters. Context Line Control -A NUM, --after-context=NUM Print NUM lines of trailing context after matching lines. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. -B NUM, --before-context=NUM Print NUM lines of leading context before matching lines. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. -C NUM, -NUM, --context=NUM Print NUM lines of output context. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. --group-separator=SEP When -A, -B, or -C are in use, print SEP instead of -- between groups of lines. --no-group-separator When -A, -B, or -C are in use, do not print a separator between groups of lines. File and Directory Selection -a, --text Process a binary file as if it were text; this is equivalent to the --binary-files=text option. --binary-files=TYPE If a file's data or metadata indicate that the file contains binary data, assume that the file is of type TYPE. Non-text bytes indicate binary data; these are either output bytes that are improperly encoded for the current locale, or null input bytes when the -z option is not given. By default, TYPE is binary, and grep suppresses output after null input binary data is discovered, and suppresses output lines that contain improperly encoded data. When some output is suppressed, grep follows any output with a message to standard error saying that a binary file matches. If TYPE is without-match, when grep discovers null input binary data it assumes that the rest of the file does not match; this is equivalent to the -I option. If TYPE is text, grep processes a binary file as if it were text; this is equivalent to the -a option. When type is binary, grep may treat non-text bytes as line terminators even without the -z option. This means choosing binary versus text can affect whether a pattern matches a file. For example, when type is binary the pattern q$ might match q immediately followed by a null byte, even though this is not matched when type is text. Conversely, when type is binary the pattern . (period) might not match a null byte. Warning: The -a option might output binary garbage, which can have nasty side effects if the output is a terminal and if the terminal driver interprets some of it as commands. On the other hand, when reading files whose text encodings are unknown, it can be helpful to use -a or to set LC_ALL='C' in the environment, in order to find more matches even if the matches are unsafe for direct display. -D ACTION, --devices=ACTION If an input file is a device, FIFO or socket, use ACTION to process it. By default, ACTION is read, which means that devices are read just as if they were ordinary files. If ACTION is skip, devices are silently skipped. -d ACTION, --directories=ACTION If an input file is a directory, use ACTION to process it. By default, ACTION is read, i.e., read directories just as if they were ordinary files. If ACTION is skip, silently skip directories. If ACTION is recurse, read all files under each directory, recursively, following symbolic links only if they are on the command line. This is equivalent to the -r option. --exclude=GLOB Skip any command-line file with a name suffix that matches the pattern GLOB, using wildcard matching; a name suffix is either the whole name, or a trailing part that starts with a non-slash character immediately after a slash (/) in the name. When searching recursively, skip any subfile whose base name matches GLOB; the base name is the part after the last slash. A pattern can use *, ?, and [...] as wildcards, and \ to quote a wildcard or backslash character literally. --exclude-from=FILE Skip files whose base name matches any of the file-name globs read from FILE (using wildcard matching as described under --exclude). --exclude-dir=GLOB Skip any command-line directory with a name suffix that matches the pattern GLOB. When searching recursively, skip any subdirectory whose base name matches GLOB. Ignore any redundant trailing slashes in GLOB. -I Process a binary file as if it did not contain matching data; this is equivalent to the --binary-files=without-match option. --include=GLOB Search only files whose base name matches GLOB (using wildcard matching as described under --exclude). If contradictory --include and --exclude options are given, the last matching one wins. If no --include or --exclude options match, a file is included unless the first such option is --include. -r, --recursive Read all files under each directory, recursively, following symbolic links only if they are on the command line. Note that if no file operand is given, grep searches the working directory. This is equivalent to the -d recurse option. -R, --dereference-recursive Read all files under each directory, recursively. Follow all symbolic links, unlike -r. Other Options --line-buffered Use line buffering on output. This can cause a performance penalty. -U, --binary Treat the file(s) as binary. By default, under MS-DOS and MS-Windows, grep guesses whether a file is text or binary as described for the --binary-files option. If grep decides the file is a text file, it strips the CR characters from the original file contents (to make regular expressions with ^ and $ work correctly). Specifying -U overrules this guesswork, causing all files to be read and passed to the matching mechanism verbatim; if the file is a text file with CR/LF pairs at the end of each line, this will cause some regular expressions to fail. This option has no effect on platforms other than MS-DOS and MS-Windows. -z, --null-data Treat input and output data as sequences of lines, each terminated by a zero byte (the ASCII NUL character) instead of a newline. Like the -Z or --null option, this option can be used with commands like sort -z to process arbitrary file names. REGULAR EXPRESSIONS top A regular expression is a pattern that describes a set of strings. Regular expressions are constructed analogously to arithmetic expressions, by using various operators to combine smaller expressions. grep understands three different versions of regular expression syntax: basic (BRE), extended (ERE) and perl (PCRE). In GNU grep, basic and extended regular expressions are merely different notations for the same pattern-matching functionality. In other implementations, basic regular expressions are ordinarily less powerful than extended, though occasionally it is the other way around. The following description applies to extended regular expressions; differences for basic regular expressions are summarized afterwards. Perl-compatible regular expressions have different functionality, and are documented in pcre2syntax(3) and pcre2pattern(3), but work only if PCRE support is enabled. The fundamental building blocks are the regular expressions that match a single character. Most characters, including all letters and digits, are regular expressions that match themselves. Any meta-character with special meaning may be quoted by preceding it with a backslash. The period . matches any single character. It is unspecified whether it matches an encoding error. Character Classes and Bracket Expressions A bracket expression is a list of characters enclosed by [ and ]. It matches any single character in that list. If the first character of the list is the caret ^ then it matches any character not in the list; it is unspecified whether it matches an encoding error. For example, the regular expression [0123456789] matches any single digit. Within a bracket expression, a range expression consists of two characters separated by a hyphen. It matches any single character that sorts between the two characters, inclusive, using the locale's collating sequence and character set. For example, in the default C locale, [a-d] is equivalent to [abcd]. Many locales sort characters in dictionary order, and in these locales [a-d] is typically not equivalent to [abcd]; it might be equivalent to [aBbCcDd], for example. To obtain the traditional interpretation of bracket expressions, you can use the C locale by setting the LC_ALL environment variable to the value C. Finally, certain named classes of characters are predefined within bracket expressions, as follows. Their names are self explanatory, and they are [:alnum:], [:alpha:], [:blank:], [:cntrl:], [:digit:], [:graph:], [:lower:], [:print:], [:punct:], [:space:], [:upper:], and [:xdigit:]. For example, [[:alnum:]] means the character class of numbers and letters in the current locale. In the C locale and ASCII character set encoding, this is the same as [0-9A-Za-z]. (Note that the brackets in these class names are part of the symbolic names, and must be included in addition to the brackets delimiting the bracket expression.) Most meta-characters lose their special meaning inside bracket expressions. To include a literal ] place it first in the list. Similarly, to include a literal ^ place it anywhere but first. Finally, to include a literal - place it last. Anchoring The caret ^ and the dollar sign $ are meta-characters that respectively match the empty string at the beginning and end of a line. The Backslash Character and Special Expressions The symbols \< and \> respectively match the empty string at the beginning and end of a word. The symbol \b matches the empty string at the edge of a word, and \B matches the empty string provided it's not at the edge of a word. The symbol \w is a synonym for [_[:alnum:]] and \W is a synonym for [^_[:alnum:]]. Repetition A regular expression may be followed by one of several repetition operators: ? The preceding item is optional and matched at most once. * The preceding item will be matched zero or more times. + The preceding item will be matched one or more times. {n} The preceding item is matched exactly n times. {n,} The preceding item is matched n or more times. {,m} The preceding item is matched at most m times. This is a GNU extension. {n,m} The preceding item is matched at least n times, but not more than m times. Concatenation Two regular expressions may be concatenated; the resulting regular expression matches any string formed by concatenating two substrings that respectively match the concatenated expressions. Alternation Two regular expressions may be joined by the infix operator |; the resulting regular expression matches any string matching either alternate expression. Precedence Repetition takes precedence over concatenation, which in turn takes precedence over alternation. A whole expression may be enclosed in parentheses to override these precedence rules and form a subexpression. Back-references and Subexpressions The back-reference \n, where n is a single digit, matches the substring previously matched by the nth parenthesized subexpression of the regular expression. Basic vs Extended Regular Expressions In basic regular expressions the meta-characters ?, +, {, |, (, and ) lose their special meaning; instead use the backslashed versions \?, \+, \{, \|, \(, and \). EXIT STATUS top Normally the exit status is 0 if a line is selected, 1 if no lines were selected, and 2 if an error occurred. However, if the -q or --quiet or --silent is used and a line is selected, the exit status is 0 even if an error occurred. ENVIRONMENT top The behavior of grep is affected by the following environment variables. The locale for category LC_foo is specified by examining the three environment variables LC_ALL, LC_foo, LANG, in that order. The first of these variables that is set specifies the locale. For example, if LC_ALL is not set, but LC_MESSAGES is set to pt_BR, then the Brazilian Portuguese locale is used for the LC_MESSAGES category. The C locale is used if none of these environment variables are set, if the locale catalog is not installed, or if grep was not compiled with national language support (NLS). The shell command locale -a lists locales that are currently available. GREP_COLORS Controls how the --color option highlights output. Its value is a colon-separated list of capabilities that defaults to ms=01;31:mc=01;31:sl=:cx=:fn=35:ln=32:bn=32:se=36 with the rv and ne boolean capabilities omitted (i.e., false). Supported capabilities are as follows. sl= SGR substring for whole selected lines (i.e., matching lines when the -v command-line option is omitted, or non-matching lines when -v is specified). If however the boolean rv capability and the -v command-line option are both specified, it applies to context matching lines instead. The default is empty (i.e., the terminal's default color pair). cx= SGR substring for whole context lines (i.e., non- matching lines when the -v command-line option is omitted, or matching lines when -v is specified). If however the boolean rv capability and the -v command-line option are both specified, it applies to selected non-matching lines instead. The default is empty (i.e., the terminal's default color pair). rv Boolean value that reverses (swaps) the meanings of the sl= and cx= capabilities when the -v command- line option is specified. The default is false (i.e., the capability is omitted). mt=01;31 SGR substring for matching non-empty text in any matching line (i.e., a selected line when the -v command-line option is omitted, or a context line when -v is specified). Setting this is equivalent to setting both ms= and mc= at once to the same value. The default is a bold red text foreground over the current line background. ms=01;31 SGR substring for matching non-empty text in a selected line. (This is only used when the -v command-line option is omitted.) The effect of the sl= (or cx= if rv) capability remains active when this kicks in. The default is a bold red text foreground over the current line background. mc=01;31 SGR substring for matching non-empty text in a context line. (This is only used when the -v command-line option is specified.) The effect of the cx= (or sl= if rv) capability remains active when this kicks in. The default is a bold red text foreground over the current line background. fn=35 SGR substring for file names prefixing any content line. The default is a magenta text foreground over the terminal's default background. ln=32 SGR substring for line numbers prefixing any content line. The default is a green text foreground over the terminal's default background. bn=32 SGR substring for byte offsets prefixing any content line. The default is a green text foreground over the terminal's default background. se=36 SGR substring for separators that are inserted between selected line fields (:), between context line fields, (-), and between groups of adjacent lines when nonzero context is specified (--). The default is a cyan text foreground over the terminal's default background. ne Boolean value that prevents clearing to the end of line using Erase in Line (EL) to Right (\33[K) each time a colorized item ends. This is needed on terminals on which EL is not supported. It is otherwise useful on terminals for which the back_color_erase (bce) boolean terminfo capability does not apply, when the chosen highlight colors do not affect the background, or when EL is too slow or causes too much flicker. The default is false (i.e., the capability is omitted). Note that boolean capabilities have no =... part. They are omitted (i.e., false) by default and become true when specified. See the Select Graphic Rendition (SGR) section in the documentation of the text terminal that is used for permitted values and their meaning as character attributes. These substring values are integers in decimal representation and can be concatenated with semicolons. grep takes care of assembling the result into a complete SGR sequence (\33[...m). Common values to concatenate include 1 for bold, 4 for underline, 5 for blink, 7 for inverse, 39 for default foreground color, 30 to 37 for foreground colors, 90 to 97 for 16-color mode foreground colors, 38;5;0 to 38;5;255 for 88-color and 256-color modes foreground colors, 49 for default background color, 40 to 47 for background colors, 100 to 107 for 16-color mode background colors, and 48;5;0 to 48;5;255 for 88-color and 256-color modes background colors. LC_ALL, LC_COLLATE, LANG These variables specify the locale for the LC_COLLATE category, which determines the collating sequence used to interpret range expressions like [a-z]. LC_ALL, LC_CTYPE, LANG These variables specify the locale for the LC_CTYPE category, which determines the type of characters, e.g., which characters are whitespace. This category also determines the character encoding, that is, whether text is encoded in UTF-8, ASCII, or some other encoding. In the C or POSIX locale, all characters are encoded as a single byte and every byte is a valid character. LC_ALL, LC_MESSAGES, LANG These variables specify the locale for the LC_MESSAGES category, which determines the language that grep uses for messages. The default C locale uses American English messages. POSIXLY_CORRECT If set, grep behaves as POSIX requires; otherwise, grep behaves more like other GNU programs. POSIX requires that options that follow file names must be treated as file names; by default, such options are permuted to the front of the operand list and are treated as options. Also, POSIX requires that unrecognized options be diagnosed as illegal, but since they are not really against the law the default is to diagnose them as invalid. NOTES top This man page is maintained only fitfully; the full documentation is often more up-to-date. COPYRIGHT top Copyright 1998-2000, 2002, 2005-2023 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. BUGS top Reporting Bugs Email bug reports to the bug-reporting address bug- grep@gnu.org. An email archive https://lists.gnu.org/mailman/listinfo/bug-grep and a bug tracker https://debbugs.gnu.org/cgi/pkgreport.cgi?package=grep are available. Known Bugs Large repetition counts in the {n,m} construct may cause grep to use lots of memory. In addition, certain other obscure regular expressions require exponential time and space, and may cause grep to run out of memory. Back-references are very slow, and may require exponential time. EXAMPLE top The following example outputs the location and contents of any line containing f and ending in .c, within all files in the current directory whose names contain g and end in .h. The -n option outputs line numbers, the -- argument treats expansions of *g*.h starting with - as file names not options, and the empty file /dev/null causes file names to be output even if only one file name happens to be of the form *g*.h. $ grep -n -- 'f.*\.c$' *g*.h /dev/null argmatch.h:1:/* definitions and prototypes for argmatch.c The only line that matches is line 1 of argmatch.h. Note that the regular expression syntax used in the pattern differs from the globbing syntax that the shell uses to match file names. SEE ALSO top Regular Manual Pages awk(1), cmp(1), diff(1), find(1), perl(1), sed(1), sort(1), xargs(1), read(2), pcre2(3), pcre2syntax(3), pcre2pattern(3), terminfo(5), glob(7), regex(7) Full Documentation A complete manual https://www.gnu.org/software/grep/manual/ is available. If the info and grep programs are properly installed at your site, the command info grep should give you access to the complete manual. COLOPHON top This page is part of the GNU grep (regular expression file search tool) project. Information about the project can be found at https://www.gnu.org/software/grep/. If you have a bug report for this manual page, send it to bug-grep@gnu.org. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/grep.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-09-14.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU grep 3.11.21-102b-dirty 2019-12-29 GREP(1) Pages that refer to this page: look(1), pmrep(1), sed(1), regex(3), regex(7), bridge(8), ip(8), tc(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. file(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training file(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | ENVIRONMENT | FILES | EXIT STATUS | EXAMPLES | SEE ALSO | STANDARDS CONFORMANCE | SECURITY | MAGIC DIRECTORY | HISTORY | LEGAL NOTICE | BUGS | TODO | AVAILABILITY | COLOPHON FILE(1) General Commands Manual FILE(1) NAME top file determine file type SYNOPSIS top [-bcdEhiklLNnprsSvzZ0] [--apple] [--exclude-quiet] [--extension] [--mime-encoding] [--mime-type] [-e testname] [-F separator] [-f namefile] [-m magicfiles] [-P name=value] file ... -C [-m magicfiles] [--help] DESCRIPTION top This manual page documents version 5.45 of the command. tests each argument in an attempt to classify it. There are three sets of tests, performed in this order: filesystem tests, magic tests, and language tests. The first test that succeeds causes the file type to be printed. The type printed will usually contain one of the words text (the file contains only printing characters and a few common control characters and is probably safe to read on an ASCII terminal), executable (the file contains the result of compiling a program in a form understandable to some UNIX kernel or another), or data meaning anything else (data is usually binary or non- printable). Exceptions are well-known file formats (core files, tar archives) that are known to contain binary data. When modifying magic files or the program itself, make sure to preserve these keywords. Users depend on knowing that all the readable files in a directory have the word text printed. Don't do as Berkeley did and change shell commands text to shell script. The filesystem tests are based on examining the return from a stat(2) system call. The program checks to see if the file is empty, or if it's some sort of special file. Any known file types appropriate to the system you are running on (sockets, symbolic links, or named pipes (FIFOs) on those systems that implement them) are intuited if they are defined in the system header file <sys/stat.h>. The magic tests are used to check for files with data in particular fixed formats. The canonical example of this is a binary executable (compiled program) a.out file, whose format is defined in <elf.h>, <a.out.h> and possibly <exec.h> in the standard include directory. These files have a magic number stored in a particular place near the beginning of the file that tells the UNIX operating system that the file is a binary executable, and which of several types thereof. The concept of a magic number has been applied by extension to data files. Any file with some invariant identifier at a small fixed offset into the file can usually be described in this way. The information identifying these files is read from the compiled magic file /usr/local/share/misc/magic.mgc, or the files in the directory /usr/local/share/misc/magic if the compiled file does not exist. In addition, if $HOME/.magic.mgc or $HOME/.magic exists, it will be used in preference to the system magic files. If a file does not match any of the entries in the magic file, it is examined to see if it seems to be a text file. ASCII, ISO-8859-x, non-ISO 8-bit extended-ASCII character sets (such as those used on Macintosh and IBM PC systems), UTF-8-encoded Unicode, UTF-16-encoded Unicode, and EBCDIC character sets can be distinguished by the different ranges and sequences of bytes that constitute printable text in each set. If a file passes any of these tests, its character set is reported. ASCII, ISO-8859-x, UTF-8, and extended-ASCII files are identified as text because they will be mostly readable on nearly any terminal; UTF-16 and EBCDIC are only character data because, while they contain text, it is text that will require translation before it can be read. In addition, will attempt to determine other characteristics of text-type files. If the lines of a file are terminated by CR, CRLF, or NEL, instead of the Unix-standard LF, this will be reported. Files that contain embedded escape sequences or overstriking will also be identified. Once has determined the character set used in a text-type file, it will attempt to determine in what language the file is written. The language tests look for particular strings (cf. <names.h>) that can appear anywhere in the first few blocks of a file. For example, the keyword .br indicates that the file is most likely a troff(1) input file, just as the keyword struct indicates a C program. These tests are less reliable than the previous two groups, so they are performed last. The language test routines also test for some miscellany (such as tar(1) archives, JSON files). Any file that cannot be identified as having been written in any of the character sets listed above is simply said to be data. OPTIONS top --apple Causes the command to output the file type and creator code as used by older MacOS versions. The code consists of eight letters, the first describing the file type, the latter the creator. This option works properly only for file formats that have the apple-style output defined. -b, --brief Do not prepend filenames to output lines (brief mode). -C, --compile Write a magic.mgc output file that contains a pre-parsed version of the magic file or directory. -c, --checking-printout Cause a checking printout of the parsed form of the magic file. This is usually used in conjunction with the -m option to debug a new magic file before installing it. -d Prints internal debugging information to stderr. -E On filesystem errors (file not found etc), instead of handling the error as regular output as POSIX mandates and keep going, issue an error message and exit. -e, --exclude testname Exclude the test named in testname from the list of tests made to determine the file type. Valid test names are: apptype EMX application type (only on EMX). ascii Various types of text files (this test will try to guess the text encoding, irrespective of the setting of the encoding option). encoding Different text encodings for soft magic tests. tokens Ignored for backwards compatibility. cdf Prints details of Compound Document Files. compress Checks for, and looks inside, compressed files. csv Checks Comma Separated Value files. elf Prints ELF file details, provided soft magic tests are enabled and the elf magic is found. json Examines JSON (RFC-7159) files by parsing them for compliance. soft Consults magic files. simh Examines SIMH tape files. tar Examines tar files by verifying the checksum of the 512 byte tar header. Excluding this test can provide more detailed content description by using the soft magic method. text A synonym for ascii. --exclude-quiet Like --exclude but ignore tests that does not know about. This is intended for compatibility with older versions of . --extension Print a slash-separated list of valid extensions for the file type found. -F, --separator separator Use the specified string as the separator between the filename and the file result returned. Defaults to :. -f, --files-from namefile Read the names of the files to be examined from namefile (one per line) before the argument list. Either namefile or at least one filename argument must be present; to test the standard input, use - as a filename argument. Please note that namefile is unwrapped and the enclosed filenames are processed when this option is encountered and before any further options processing is done. This allows one to process multiple lists of files with different command line arguments on the same invocation. Thus if you want to set the delimiter, you need to do it before you specify the list of files, like: -F @ -f namefile, instead of: -f namefile -F @. -h, --no-dereference This option causes symlinks not to be followed (on systems that support symbolic links). This is the default if the environment variable POSIXLY_CORRECT is not defined. -i, --mime Causes the command to output mime type strings rather than the more traditional human readable ones. Thus it may say text/plain; charset=us-ascii rather than ASCII text. --mime-type, --mime-encoding Like -i, but print only the specified element(s). -k, --keep-going Don't stop at the first match, keep going. Subsequent matches will be have the string \012- prepended. (If you want a newline, see the -r option.) The magic pattern with the highest strength (see the -l option) comes first. -l, --list Shows a list of patterns and their strength sorted descending by magic(4) strength which is used for the matching (see also the -k option). -L, --dereference This option causes symlinks to be followed, as the like- named option in ls(1) (on systems that support symbolic links). This is the default if the environment variable POSIXLY_CORRECT is defined. -m, --magic-file magicfiles Specify an alternate list of files and directories containing magic. This can be a single item, or a colon- separated list. If a compiled magic file is found alongside a file or directory, it will be used instead. -N, --no-pad Don't pad filenames so that they align in the output. -n, --no-buffer Force stdout to be flushed after checking each file. This is only useful if checking a list of files. It is intended to be used by programs that want filetype output from a pipe. -p, --preserve-date On systems that support utime(3) or utimes(2), attempt to preserve the access time of files analyzed, to pretend that never read them. -P, --parameter name=value Set various parameter limits. Name Default Explanation bytes 1M max number of bytes to read from file elf_notes 256 max ELF notes processed elf_phnum 2K max ELF program sections processed elf_shnum 32K max ELF sections processed elf_shsize 128MB max ELF section size processed encoding 65K max number of bytes to determine encoding indir 50 recursion limit for indirect magic name 50 use count limit for name/use magic regex 8K length limit for regex searches -r, --raw Don't translate unprintable characters to \ooo. Normally translates unprintable characters to their octal representation. -s, --special-files Normally, only attempts to read and determine the type of argument files which stat(2) reports are ordinary files. This prevents problems, because reading special files may have peculiar consequences. Specifying the -s option causes to also read argument files which are block or character special files. This is useful for determining the filesystem types of the data in raw disk partitions, which are block special files. This option also causes to disregard the file size as reported by stat(2) since on some systems it reports a zero size for raw disk partitions. -S, --no-sandbox On systems where libseccomp (https://github.com/seccomp/libseccomp ) is available, the -S option disables sandboxing which is enabled by default. This option is needed for to execute external decompressing programs, i.e. when the -z option is specified and the built-in decompressors are not available. On systems where sandboxing is not available, this option has no effect. -v, --version Print the version of the program and exit. -z, --uncompress Try to look inside compressed files. -Z, --uncompress-noreport Try to look inside compressed files, but report information about the contents only not the compression. -0, --print0 Output a null character \0 after the end of the filename. Nice to cut(1) the output. This does not affect the separator, which is still printed. If this option is repeated more than once, then prints just the filename followed by a NUL followed by the description (or ERROR: text) followed by a second NUL for each entry. --help Print a help message and exit. ENVIRONMENT top The environment variable MAGIC can be used to set the default magic file name. If that variable is set, then will not attempt to open $HOME/.magic. adds .mgc to the value of this variable as appropriate. The environment variable POSIXLY_CORRECT controls (on systems that support symbolic links), whether will attempt to follow symlinks or not. If set, then follows symlink, otherwise it does not. This is also controlled by the -L and -h options. FILES top /usr/local/share/misc/magic.mgc Default compiled list of magic. /usr/local/share/misc/magic Directory containing default magic files. EXIT STATUS top will exit with 0 if the operation was successful or >0 if an error was encountered. The following errors cause diagnostic messages, but don't affect the program exit code (as POSIX requires), unless -E is specified: A file cannot be found There is no permission to read a file The file type cannot be determined EXAMPLES top $ file file.c file /dev/{wd0a,hda} file.c: C program text file: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked (uses shared libs), stripped /dev/wd0a: block special (0/0) /dev/hda: block special (3/0) $ file -s /dev/wd0{b,d} /dev/wd0b: data /dev/wd0d: x86 boot sector $ file -s /dev/hda{,1,2,3,4,5,6,7,8,9,10} /dev/hda: x86 boot sector /dev/hda1: Linux/i386 ext2 filesystem /dev/hda2: x86 boot sector /dev/hda3: x86 boot sector, extended partition table /dev/hda4: Linux/i386 ext2 filesystem /dev/hda5: Linux/i386 swap file /dev/hda6: Linux/i386 swap file /dev/hda7: Linux/i386 swap file /dev/hda8: Linux/i386 swap file /dev/hda9: empty /dev/hda10: empty $ file -i file.c file /dev/{wd0a,hda} file.c: text/x-c file: application/x-executable /dev/hda: application/x-not-regular-file /dev/wd0a: application/x-not-regular-file SEE ALSO top hexdump(1), od(1), strings(1), magic(4) STANDARDS CONFORMANCE top This program is believed to exceed the System V Interface Definition of FILE(CMD), as near as one can determine from the vague language contained therein. Its behavior is mostly compatible with the System V program of the same name. This version knows more magic, however, so it will produce different (albeit more accurate) output in many cases. The one significant difference between this version and System V is that this version treats any white space as a delimiter, so that spaces in pattern strings must be escaped. For example, >10 string language impress (imPRESS data) in an existing magic file would have to be changed to >10 string language\ impress (imPRESS data) In addition, in this version, if a pattern string contains a backslash, it must be escaped. For example 0 string \begindata Andrew Toolkit document in an existing magic file would have to be changed to 0 string \\begindata Andrew Toolkit document SunOS releases 3.2 and later from Sun Microsystems include a command derived from the System V one, but with some extensions. This version differs from Sun's only in minor ways. It includes the extension of the & operator, used as, for example, >16 long&0x7fffffff >0 not stripped SECURITY top On systems where libseccomp (https://github.com/seccomp/libseccomp ) is available, is enforces limiting system calls to only the ones necessary for the operation of the program. This enforcement does not provide any security benefit when is asked to decompress input files running external programs with the -z option. To enable execution of external decompressors, one needs to disable sandboxing using the -S option. MAGIC DIRECTORY top The magic file entries have been collected from various sources, mainly USENET, and contributed by various authors. Christos Zoulas (address below) will collect additional or corrected magic file entries. A consolidation of magic file entries will be distributed periodically. The order of entries in the magic file is significant. Depending on what system you are using, the order that they are put together may be incorrect. If your old command uses a magic file, keep the old magic file around for comparison purposes (rename it to /usr/local/share/misc/magic.orig). HISTORY top There has been a command in every UNIX since at least Research Version 4 (man page dated November, 1973). The System V version introduced one significant major change: the external list of magic types. This slowed the program down slightly but made it a lot more flexible. This program, based on the System V version, was written by Ian Darwin ian@darwinsys.com without looking at anybody else's source code. John Gilmore revised the code extensively, making it better than the first version. Geoff Collyer found several inadequacies and provided some magic file entries. Contributions of the & operator by Rob McMahon, cudcv@warwick.ac.uk, 1989. Guy Harris, guy@netapp.com, made many changes from 1993 to the present. Primary development and maintenance from 1990 to the present by Christos Zoulas christos@astron.com. Altered by Chris Lowth chris@lowth.com, 2000: handle the -i option to output mime type strings, using an alternative magic file and internal logic. Altered by Eric Fischer enf@pobox.com, July, 2000, to identify character codes and attempt to identify the languages of non- ASCII files. Altered by Reuben Thomas rrt@sc3d.org, 2007-2011, to improve MIME support, merge MIME and non-MIME magic, support directories as well as files of magic, apply many bug fixes, update and fix a lot of magic, improve the build system, improve the documentation, and rewrite the Python bindings in pure Python. The list of contributors to the magic directory (magic files) is too long to include here. You know who you are; thank you. Many contributors are listed in the source files. LEGAL NOTICE top Copyright (c) Ian F. Darwin, Toronto, Canada, 1986-1999. Covered by the standard Berkeley Software Distribution copyright; see the file COPYING in the source distribution. The files tar.h and is_tar.c were written by John Gilmore from his public-domain tar(1) program, and are not covered by the above license. BUGS top Please report bugs and send patches to the bug tracker at https://bugs.astron.com/ or the mailing list at file@astron.com (visit https://mailman.astron.com/mailman/listinfo/file first to subscribe). TODO top Fix output so that tests for MIME and APPLE flags are not needed all over the place, and actual output is only done in one place. This needs a design. Suggestion: push possible outputs on to a list, then pick the last-pushed (most specific, one hopes) value at the end, or use a default if the list is empty. This should not slow down evaluation. The handling of MAGIC_CONTINUE and printing \012- between entries is clumsy and complicated; refactor and centralize. Some of the encoding logic is hard-coded in encoding.c and can be moved to the magic files if we had a !:charset annotation. Continue to squash all magic bugs. See Debian BTS for a good source. Store arbitrarily long strings, for example for %s patterns, so that they can be printed out. Fixes Debian bug #271672. This can be done by allocating strings in a string pool, storing the string pool at the end of the magic file and converting all the string pointers to relative offsets from the string pool. Add syntax for relative offsets after current level (Debian bug #466037). Make file -ki work, i.e. give multiple MIME types. Add a zip library so we can peek inside Office2007 documents to print more details about their contents. Add an option to print URLs for the sources of the file descriptions. Combine script searches and add a way to map executable names to MIME types (e.g. have a magic value for !:mime which causes the resulting string to be looked up in a table). This would avoid adding the same magic repeatedly for each new hash-bang interpreter. When a file descriptor is available, we can skip and adjust the buffer instead of the hacky buffer management we do now. Fix name and use to check for consistency at compile time (duplicate name, use pointing to undefined name ). Make name / use more efficient by keeping a sorted list of names. Special-case ^ to flip endianness in the parser so that it does not have to be escaped, and document it. If the offsets specified internally in the file exceed the buffer size ( HOWMANY variable in file.h), then we don't seek to that offset, but we give up. It would be better if buffer managements was done when the file descriptor is available so we can seek around the file. One must be careful though because this has performance and thus security considerations, because one can slow down things by repeatedly seeking. There is support now for keeping separate buffers and having offsets from the end of the file, but the internal buffer management still needs an overhaul. AVAILABILITY top You can obtain the original author's latest version by anonymous FTP on ftp.astron.com in the directory /pub/file/file-X.YZ.tar.gz. COLOPHON top This page is part of the file (a file type guesser) project. Information about the project can be found at http://www.darwinsys.com/file/. If you have a bug report for this manual page, see http://bugs.gw.com/my_view_page.php. This page was obtained from the project's upstream Git read-only mirror of the CVS repository https://github.com/glensc/file on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-12-21.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU May 21, 2023 FILE(1) Pages that refer to this page: dh_installmanpages(1), dh_strip(1), ippeveprinter(1), pmcd(1), scr_dump(5), term(5), suffixes(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Decompress "path/to/test/file.gz" to standard output and save all lines matching "my regex" and not matching "other regex" to files with a 1000000 line limit Bash Command:<START>gzip -dc path/to/test/file.gz | grep -P 'my regex' | grep -vP 'other regex' | split -dl1000000 - file<END>

Decompress "path/to/test/file.gz" to standard output and save all lines matching "my regex" to files with a 1000000 line limit

gzip -dc path/to/test/file.gz | grep -P --regexp='my regex' | split -dl1000000 - file

['split', 'grep', 'file']

Output a Bash command to accomplish the following task. Task: Decompress "path/to/test/file.gz" to standard output and save all lines matching "my regex" to files with a 1000000 line limit Bash Command:<START>gzip -dc path/to/test/file.gz | grep -P --regexp='my regex' | split -dl1000000 - file<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # split\n\n> Split a file into pieces.\n> More information: <https://www.gnu.org/software/coreutils/split>.\n\n- Split a file, each split having 10 lines (except the last split):\n\n`split -l {{10}} {{path/to/file}}`\n\n- Split a file into 5 files. File is split such that each split has same size (except the last split):\n\n`split -n {{5}} {{path/to/file}}`\n\n- Split a file with 512 bytes in each split (except the last split; use 512k for kilobytes and 512m for megabytes):\n\n`split -b {{512}} {{path/to/file}}`\n\n- Split a file with at most 512 bytes in each split without breaking lines:\n\n`split -C {{512}} {{path/to/file}}`\n # grep\n\n> Find patterns in files using regular expressions.\n> More information: <https://www.gnu.org/software/grep/manual/grep.html>.\n\n- Search for a pattern within a file:\n\n`grep "{{search_pattern}}" {{path/to/file}}`\n\n- Search for an exact string (disables regular expressions):\n\n`grep --fixed-strings "{{exact_string}}" {{path/to/file}}`\n\n- Search for a pattern in all files recursively in a directory, showing line numbers of matches, ignoring binary files:\n\n`grep --recursive --line-number --binary-files={{without-match}} "{{search_pattern}}" {{path/to/directory}}`\n\n- Use extended regular expressions (supports `?`, `+`, `{}`, `()` and `|`), in case-insensitive mode:\n\n`grep --extended-regexp --ignore-case "{{search_pattern}}" {{path/to/file}}`\n\n- Print 3 lines of context around, before, or after each match:\n\n`grep --{{context|before-context|after-context}}={{3}} "{{search_pattern}}" {{path/to/file}}`\n\n- Print file name and line number for each match with color output:\n\n`grep --with-filename --line-number --color=always "{{search_pattern}}" {{path/to/file}}`\n\n- Search for lines matching a pattern, printing only the matched text:\n\n`grep --only-matching "{{search_pattern}}" {{path/to/file}}`\n\n- Search `stdin` for lines that do not match a pattern:\n\n`cat {{path/to/file}} | grep --invert-match "{{search_pattern}}"`\n # file\n\n> Determine file type.\n> More information: <https://manned.org/file>.\n\n- Give a description of the type of the specified file. Works fine for files with no file extension:\n\n`file {{path/to/file}}`\n\n- Look inside a zipped file and determine the file type(s) inside:\n\n`file -z {{foo.zip}}`\n\n- Allow file to work with special or device files:\n\n`file -s {{path/to/file}}`\n\n- Don't stop at first file type match; keep going until the end of the file:\n\n`file -k {{path/to/file}}`\n\n- Determine the MIME encoding type of a file:\n\n`file -i {{path/to/file}}`\n Task: Decompress "path/to/test/file.gz" to standard output and save all lines matching "my regex" to files with a 1000000 line limit Bash Command:<START>gzip -dc path/to/test/file.gz | grep -P --regexp='my regex' | split -dl1000000 - file<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: split(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training split(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON SPLIT(1) User Commands SPLIT(1) NAME top split - split a file into pieces SYNOPSIS top split [OPTION]... [FILE [PREFIX]] DESCRIPTION top Output pieces of FILE to PREFIXaa, PREFIXab, ...; default size is 1000 lines, and default PREFIX is 'x'. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -a, --suffix-length=N generate suffixes of length N (default 2) --additional-suffix=SUFFIX append an additional SUFFIX to file names -b, --bytes=SIZE put SIZE bytes per output file -C, --line-bytes=SIZE put at most SIZE bytes of records per output file -d use numeric suffixes starting at 0, not alphabetic --numeric-suffixes[=FROM] same as -d, but allow setting the start value -x use hex suffixes starting at 0, not alphabetic --hex-suffixes[=FROM] same as -x, but allow setting the start value -e, --elide-empty-files do not generate empty output files with '-n' --filter=COMMAND write to shell COMMAND; file name is $FILE -l, --lines=NUMBER put NUMBER lines/records per output file -n, --number=CHUNKS generate CHUNKS output files; see explanation below -t, --separator=SEP use SEP instead of newline as the record separator; '\0' (zero) specifies the NUL character -u, --unbuffered immediately copy input to output with '-n r/...' --verbose print a diagnostic just before each output file is opened --help display this help and exit --version output version information and exit The SIZE argument is an integer and optional unit (example: 10K is 10*1024). Units are K,M,G,T,P,E,Z,Y,R,Q (powers of 1024) or KB,MB,... (powers of 1000). Binary prefixes can be used, too: KiB=K, MiB=M, and so on. CHUNKS may be: N split into N files based on size of input K/N output Kth of N to stdout l/N split into N files without splitting lines/records l/K/N output Kth of N to stdout without splitting lines/records r/N like 'l' but use round robin distribution r/K/N likewise but only output Kth of N to stdout AUTHOR top Written by Torbjorn Granlund and Richard M. Stallman. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top Full documentation <https://www.gnu.org/software/coreutils/split> or available locally via: info '(coreutils) split invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 SPLIT(1) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. grep(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training grep(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | REGULAR EXPRESSIONS | EXIT STATUS | ENVIRONMENT | NOTES | COPYRIGHT | BUGS | EXAMPLE | SEE ALSO | COLOPHON GREP(1) User Commands GREP(1) NAME top grep - print lines that match patterns SYNOPSIS top grep [OPTION...] PATTERNS [FILE...] grep [OPTION...] -e PATTERNS ... [FILE...] grep [OPTION...] -f PATTERN_FILE ... [FILE...] DESCRIPTION top grep searches for PATTERNS in each FILE. PATTERNS is one or more patterns separated by newline characters, and grep prints each line that matches a pattern. Typically PATTERNS should be quoted when grep is used in a shell command. A FILE of - stands for standard input. If no FILE is given, recursive searches examine the working directory, and nonrecursive searches read standard input. OPTIONS top Generic Program Information --help Output a usage message and exit. -V, --version Output the version number of grep and exit. Pattern Syntax -E, --extended-regexp Interpret PATTERNS as extended regular expressions (EREs, see below). -F, --fixed-strings Interpret PATTERNS as fixed strings, not regular expressions. -G, --basic-regexp Interpret PATTERNS as basic regular expressions (BREs, see below). This is the default. -P, --perl-regexp Interpret PATTERNS as Perl-compatible regular expressions (PCREs). This option is experimental when combined with the -z (--null-data) option, and grep -P may warn of unimplemented features. Matching Control -e PATTERNS, --regexp=PATTERNS Use PATTERNS as the patterns. If this option is used multiple times or is combined with the -f (--file) option, search for all patterns given. This option can be used to protect a pattern beginning with -. -f FILE, --file=FILE Obtain patterns from FILE, one per line. If this option is used multiple times or is combined with the -e (--regexp) option, search for all patterns given. The empty file contains zero patterns, and therefore matches nothing. If FILE is - , read patterns from standard input. -i, --ignore-case Ignore case distinctions in patterns and input data, so that characters that differ only in case match each other. --no-ignore-case Do not ignore case distinctions in patterns and input data. This is the default. This option is useful for passing to shell scripts that already use -i, to cancel its effects because the two options override each other. -v, --invert-match Invert the sense of matching, to select non-matching lines. -w, --word-regexp Select only those lines containing matches that form whole words. The test is that the matching substring must either be at the beginning of the line, or preceded by a non-word constituent character. Similarly, it must be either at the end of the line or followed by a non-word constituent character. Word-constituent characters are letters, digits, and the underscore. This option has no effect if -x is also specified. -x, --line-regexp Select only those matches that exactly match the whole line. For a regular expression pattern, this is like parenthesizing the pattern and then surrounding it with ^ and $. General Output Control -c, --count Suppress normal output; instead print a count of matching lines for each input file. With the -v, --invert-match option (see above), count non-matching lines. --color[=WHEN], --colour[=WHEN] Surround the matched (non-empty) strings, matching lines, context lines, file names, line numbers, byte offsets, and separators (for fields and groups of context lines) with escape sequences to display them in color on the terminal. The colors are defined by the environment variable GREP_COLORS. WHEN is never, always, or auto. -L, --files-without-match Suppress normal output; instead print the name of each input file from which no output would normally have been printed. -l, --files-with-matches Suppress normal output; instead print the name of each input file from which output would normally have been printed. Scanning each input file stops upon first match. -m NUM, --max-count=NUM Stop reading a file after NUM matching lines. If NUM is zero, grep stops right away without reading input. A NUM of -1 is treated as infinity and grep does not stop; this is the default. If the input is standard input from a regular file, and NUM matching lines are output, grep ensures that the standard input is positioned to just after the last matching line before exiting, regardless of the presence of trailing context lines. This enables a calling process to resume a search. When grep stops after NUM matching lines, it outputs any trailing context lines. When the -c or --count option is also used, grep does not output a count greater than NUM. When the -v or --invert-match option is also used, grep stops after outputting NUM non-matching lines. -o, --only-matching Print only the matched (non-empty) parts of a matching line, with each such part on a separate output line. -q, --quiet, --silent Quiet; do not write anything to standard output. Exit immediately with zero status if any match is found, even if an error was detected. Also see the -s or --no-messages option. -s, --no-messages Suppress error messages about nonexistent or unreadable files. Output Line Prefix Control -b, --byte-offset Print the 0-based byte offset within the input file before each line of output. If -o (--only-matching) is specified, print the offset of the matching part itself. -H, --with-filename Print the file name for each match. This is the default when there is more than one file to search. This is a GNU extension. -h, --no-filename Suppress the prefixing of file names on output. This is the default when there is only one file (or only standard input) to search. --label=LABEL Display input actually coming from standard input as input coming from file LABEL. This can be useful for commands that transform a file's contents before searching, e.g., gzip -cd foo.gz | grep --label=foo -H 'some pattern'. See also the -H option. -n, --line-number Prefix each line of output with the 1-based line number within its input file. -T, --initial-tab Make sure that the first character of actual line content lies on a tab stop, so that the alignment of tabs looks normal. This is useful with options that prefix their output to the actual content: -H,-n, and -b. In order to improve the probability that lines from a single file will all start at the same column, this also causes the line number and byte offset (if present) to be printed in a minimum size field width. -Z, --null Output a zero byte (the ASCII NUL character) instead of the character that normally follows a file name. For example, grep -lZ outputs a zero byte after each file name instead of the usual newline. This option makes the output unambiguous, even in the presence of file names containing unusual characters like newlines. This option can be used with commands like find -print0, perl -0, sort -z, and xargs -0 to process arbitrary file names, even those that contain newline characters. Context Line Control -A NUM, --after-context=NUM Print NUM lines of trailing context after matching lines. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. -B NUM, --before-context=NUM Print NUM lines of leading context before matching lines. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. -C NUM, -NUM, --context=NUM Print NUM lines of output context. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. --group-separator=SEP When -A, -B, or -C are in use, print SEP instead of -- between groups of lines. --no-group-separator When -A, -B, or -C are in use, do not print a separator between groups of lines. File and Directory Selection -a, --text Process a binary file as if it were text; this is equivalent to the --binary-files=text option. --binary-files=TYPE If a file's data or metadata indicate that the file contains binary data, assume that the file is of type TYPE. Non-text bytes indicate binary data; these are either output bytes that are improperly encoded for the current locale, or null input bytes when the -z option is not given. By default, TYPE is binary, and grep suppresses output after null input binary data is discovered, and suppresses output lines that contain improperly encoded data. When some output is suppressed, grep follows any output with a message to standard error saying that a binary file matches. If TYPE is without-match, when grep discovers null input binary data it assumes that the rest of the file does not match; this is equivalent to the -I option. If TYPE is text, grep processes a binary file as if it were text; this is equivalent to the -a option. When type is binary, grep may treat non-text bytes as line terminators even without the -z option. This means choosing binary versus text can affect whether a pattern matches a file. For example, when type is binary the pattern q$ might match q immediately followed by a null byte, even though this is not matched when type is text. Conversely, when type is binary the pattern . (period) might not match a null byte. Warning: The -a option might output binary garbage, which can have nasty side effects if the output is a terminal and if the terminal driver interprets some of it as commands. On the other hand, when reading files whose text encodings are unknown, it can be helpful to use -a or to set LC_ALL='C' in the environment, in order to find more matches even if the matches are unsafe for direct display. -D ACTION, --devices=ACTION If an input file is a device, FIFO or socket, use ACTION to process it. By default, ACTION is read, which means that devices are read just as if they were ordinary files. If ACTION is skip, devices are silently skipped. -d ACTION, --directories=ACTION If an input file is a directory, use ACTION to process it. By default, ACTION is read, i.e., read directories just as if they were ordinary files. If ACTION is skip, silently skip directories. If ACTION is recurse, read all files under each directory, recursively, following symbolic links only if they are on the command line. This is equivalent to the -r option. --exclude=GLOB Skip any command-line file with a name suffix that matches the pattern GLOB, using wildcard matching; a name suffix is either the whole name, or a trailing part that starts with a non-slash character immediately after a slash (/) in the name. When searching recursively, skip any subfile whose base name matches GLOB; the base name is the part after the last slash. A pattern can use *, ?, and [...] as wildcards, and \ to quote a wildcard or backslash character literally. --exclude-from=FILE Skip files whose base name matches any of the file-name globs read from FILE (using wildcard matching as described under --exclude). --exclude-dir=GLOB Skip any command-line directory with a name suffix that matches the pattern GLOB. When searching recursively, skip any subdirectory whose base name matches GLOB. Ignore any redundant trailing slashes in GLOB. -I Process a binary file as if it did not contain matching data; this is equivalent to the --binary-files=without-match option. --include=GLOB Search only files whose base name matches GLOB (using wildcard matching as described under --exclude). If contradictory --include and --exclude options are given, the last matching one wins. If no --include or --exclude options match, a file is included unless the first such option is --include. -r, --recursive Read all files under each directory, recursively, following symbolic links only if they are on the command line. Note that if no file operand is given, grep searches the working directory. This is equivalent to the -d recurse option. -R, --dereference-recursive Read all files under each directory, recursively. Follow all symbolic links, unlike -r. Other Options --line-buffered Use line buffering on output. This can cause a performance penalty. -U, --binary Treat the file(s) as binary. By default, under MS-DOS and MS-Windows, grep guesses whether a file is text or binary as described for the --binary-files option. If grep decides the file is a text file, it strips the CR characters from the original file contents (to make regular expressions with ^ and $ work correctly). Specifying -U overrules this guesswork, causing all files to be read and passed to the matching mechanism verbatim; if the file is a text file with CR/LF pairs at the end of each line, this will cause some regular expressions to fail. This option has no effect on platforms other than MS-DOS and MS-Windows. -z, --null-data Treat input and output data as sequences of lines, each terminated by a zero byte (the ASCII NUL character) instead of a newline. Like the -Z or --null option, this option can be used with commands like sort -z to process arbitrary file names. REGULAR EXPRESSIONS top A regular expression is a pattern that describes a set of strings. Regular expressions are constructed analogously to arithmetic expressions, by using various operators to combine smaller expressions. grep understands three different versions of regular expression syntax: basic (BRE), extended (ERE) and perl (PCRE). In GNU grep, basic and extended regular expressions are merely different notations for the same pattern-matching functionality. In other implementations, basic regular expressions are ordinarily less powerful than extended, though occasionally it is the other way around. The following description applies to extended regular expressions; differences for basic regular expressions are summarized afterwards. Perl-compatible regular expressions have different functionality, and are documented in pcre2syntax(3) and pcre2pattern(3), but work only if PCRE support is enabled. The fundamental building blocks are the regular expressions that match a single character. Most characters, including all letters and digits, are regular expressions that match themselves. Any meta-character with special meaning may be quoted by preceding it with a backslash. The period . matches any single character. It is unspecified whether it matches an encoding error. Character Classes and Bracket Expressions A bracket expression is a list of characters enclosed by [ and ]. It matches any single character in that list. If the first character of the list is the caret ^ then it matches any character not in the list; it is unspecified whether it matches an encoding error. For example, the regular expression [0123456789] matches any single digit. Within a bracket expression, a range expression consists of two characters separated by a hyphen. It matches any single character that sorts between the two characters, inclusive, using the locale's collating sequence and character set. For example, in the default C locale, [a-d] is equivalent to [abcd]. Many locales sort characters in dictionary order, and in these locales [a-d] is typically not equivalent to [abcd]; it might be equivalent to [aBbCcDd], for example. To obtain the traditional interpretation of bracket expressions, you can use the C locale by setting the LC_ALL environment variable to the value C. Finally, certain named classes of characters are predefined within bracket expressions, as follows. Their names are self explanatory, and they are [:alnum:], [:alpha:], [:blank:], [:cntrl:], [:digit:], [:graph:], [:lower:], [:print:], [:punct:], [:space:], [:upper:], and [:xdigit:]. For example, [[:alnum:]] means the character class of numbers and letters in the current locale. In the C locale and ASCII character set encoding, this is the same as [0-9A-Za-z]. (Note that the brackets in these class names are part of the symbolic names, and must be included in addition to the brackets delimiting the bracket expression.) Most meta-characters lose their special meaning inside bracket expressions. To include a literal ] place it first in the list. Similarly, to include a literal ^ place it anywhere but first. Finally, to include a literal - place it last. Anchoring The caret ^ and the dollar sign $ are meta-characters that respectively match the empty string at the beginning and end of a line. The Backslash Character and Special Expressions The symbols \< and \> respectively match the empty string at the beginning and end of a word. The symbol \b matches the empty string at the edge of a word, and \B matches the empty string provided it's not at the edge of a word. The symbol \w is a synonym for [_[:alnum:]] and \W is a synonym for [^_[:alnum:]]. Repetition A regular expression may be followed by one of several repetition operators: ? The preceding item is optional and matched at most once. * The preceding item will be matched zero or more times. + The preceding item will be matched one or more times. {n} The preceding item is matched exactly n times. {n,} The preceding item is matched n or more times. {,m} The preceding item is matched at most m times. This is a GNU extension. {n,m} The preceding item is matched at least n times, but not more than m times. Concatenation Two regular expressions may be concatenated; the resulting regular expression matches any string formed by concatenating two substrings that respectively match the concatenated expressions. Alternation Two regular expressions may be joined by the infix operator |; the resulting regular expression matches any string matching either alternate expression. Precedence Repetition takes precedence over concatenation, which in turn takes precedence over alternation. A whole expression may be enclosed in parentheses to override these precedence rules and form a subexpression. Back-references and Subexpressions The back-reference \n, where n is a single digit, matches the substring previously matched by the nth parenthesized subexpression of the regular expression. Basic vs Extended Regular Expressions In basic regular expressions the meta-characters ?, +, {, |, (, and ) lose their special meaning; instead use the backslashed versions \?, \+, \{, \|, \(, and \). EXIT STATUS top Normally the exit status is 0 if a line is selected, 1 if no lines were selected, and 2 if an error occurred. However, if the -q or --quiet or --silent is used and a line is selected, the exit status is 0 even if an error occurred. ENVIRONMENT top The behavior of grep is affected by the following environment variables. The locale for category LC_foo is specified by examining the three environment variables LC_ALL, LC_foo, LANG, in that order. The first of these variables that is set specifies the locale. For example, if LC_ALL is not set, but LC_MESSAGES is set to pt_BR, then the Brazilian Portuguese locale is used for the LC_MESSAGES category. The C locale is used if none of these environment variables are set, if the locale catalog is not installed, or if grep was not compiled with national language support (NLS). The shell command locale -a lists locales that are currently available. GREP_COLORS Controls how the --color option highlights output. Its value is a colon-separated list of capabilities that defaults to ms=01;31:mc=01;31:sl=:cx=:fn=35:ln=32:bn=32:se=36 with the rv and ne boolean capabilities omitted (i.e., false). Supported capabilities are as follows. sl= SGR substring for whole selected lines (i.e., matching lines when the -v command-line option is omitted, or non-matching lines when -v is specified). If however the boolean rv capability and the -v command-line option are both specified, it applies to context matching lines instead. The default is empty (i.e., the terminal's default color pair). cx= SGR substring for whole context lines (i.e., non- matching lines when the -v command-line option is omitted, or matching lines when -v is specified). If however the boolean rv capability and the -v command-line option are both specified, it applies to selected non-matching lines instead. The default is empty (i.e., the terminal's default color pair). rv Boolean value that reverses (swaps) the meanings of the sl= and cx= capabilities when the -v command- line option is specified. The default is false (i.e., the capability is omitted). mt=01;31 SGR substring for matching non-empty text in any matching line (i.e., a selected line when the -v command-line option is omitted, or a context line when -v is specified). Setting this is equivalent to setting both ms= and mc= at once to the same value. The default is a bold red text foreground over the current line background. ms=01;31 SGR substring for matching non-empty text in a selected line. (This is only used when the -v command-line option is omitted.) The effect of the sl= (or cx= if rv) capability remains active when this kicks in. The default is a bold red text foreground over the current line background. mc=01;31 SGR substring for matching non-empty text in a context line. (This is only used when the -v command-line option is specified.) The effect of the cx= (or sl= if rv) capability remains active when this kicks in. The default is a bold red text foreground over the current line background. fn=35 SGR substring for file names prefixing any content line. The default is a magenta text foreground over the terminal's default background. ln=32 SGR substring for line numbers prefixing any content line. The default is a green text foreground over the terminal's default background. bn=32 SGR substring for byte offsets prefixing any content line. The default is a green text foreground over the terminal's default background. se=36 SGR substring for separators that are inserted between selected line fields (:), between context line fields, (-), and between groups of adjacent lines when nonzero context is specified (--). The default is a cyan text foreground over the terminal's default background. ne Boolean value that prevents clearing to the end of line using Erase in Line (EL) to Right (\33[K) each time a colorized item ends. This is needed on terminals on which EL is not supported. It is otherwise useful on terminals for which the back_color_erase (bce) boolean terminfo capability does not apply, when the chosen highlight colors do not affect the background, or when EL is too slow or causes too much flicker. The default is false (i.e., the capability is omitted). Note that boolean capabilities have no =... part. They are omitted (i.e., false) by default and become true when specified. See the Select Graphic Rendition (SGR) section in the documentation of the text terminal that is used for permitted values and their meaning as character attributes. These substring values are integers in decimal representation and can be concatenated with semicolons. grep takes care of assembling the result into a complete SGR sequence (\33[...m). Common values to concatenate include 1 for bold, 4 for underline, 5 for blink, 7 for inverse, 39 for default foreground color, 30 to 37 for foreground colors, 90 to 97 for 16-color mode foreground colors, 38;5;0 to 38;5;255 for 88-color and 256-color modes foreground colors, 49 for default background color, 40 to 47 for background colors, 100 to 107 for 16-color mode background colors, and 48;5;0 to 48;5;255 for 88-color and 256-color modes background colors. LC_ALL, LC_COLLATE, LANG These variables specify the locale for the LC_COLLATE category, which determines the collating sequence used to interpret range expressions like [a-z]. LC_ALL, LC_CTYPE, LANG These variables specify the locale for the LC_CTYPE category, which determines the type of characters, e.g., which characters are whitespace. This category also determines the character encoding, that is, whether text is encoded in UTF-8, ASCII, or some other encoding. In the C or POSIX locale, all characters are encoded as a single byte and every byte is a valid character. LC_ALL, LC_MESSAGES, LANG These variables specify the locale for the LC_MESSAGES category, which determines the language that grep uses for messages. The default C locale uses American English messages. POSIXLY_CORRECT If set, grep behaves as POSIX requires; otherwise, grep behaves more like other GNU programs. POSIX requires that options that follow file names must be treated as file names; by default, such options are permuted to the front of the operand list and are treated as options. Also, POSIX requires that unrecognized options be diagnosed as illegal, but since they are not really against the law the default is to diagnose them as invalid. NOTES top This man page is maintained only fitfully; the full documentation is often more up-to-date. COPYRIGHT top Copyright 1998-2000, 2002, 2005-2023 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. BUGS top Reporting Bugs Email bug reports to the bug-reporting address bug- grep@gnu.org. An email archive https://lists.gnu.org/mailman/listinfo/bug-grep and a bug tracker https://debbugs.gnu.org/cgi/pkgreport.cgi?package=grep are available. Known Bugs Large repetition counts in the {n,m} construct may cause grep to use lots of memory. In addition, certain other obscure regular expressions require exponential time and space, and may cause grep to run out of memory. Back-references are very slow, and may require exponential time. EXAMPLE top The following example outputs the location and contents of any line containing f and ending in .c, within all files in the current directory whose names contain g and end in .h. The -n option outputs line numbers, the -- argument treats expansions of *g*.h starting with - as file names not options, and the empty file /dev/null causes file names to be output even if only one file name happens to be of the form *g*.h. $ grep -n -- 'f.*\.c$' *g*.h /dev/null argmatch.h:1:/* definitions and prototypes for argmatch.c The only line that matches is line 1 of argmatch.h. Note that the regular expression syntax used in the pattern differs from the globbing syntax that the shell uses to match file names. SEE ALSO top Regular Manual Pages awk(1), cmp(1), diff(1), find(1), perl(1), sed(1), sort(1), xargs(1), read(2), pcre2(3), pcre2syntax(3), pcre2pattern(3), terminfo(5), glob(7), regex(7) Full Documentation A complete manual https://www.gnu.org/software/grep/manual/ is available. If the info and grep programs are properly installed at your site, the command info grep should give you access to the complete manual. COLOPHON top This page is part of the GNU grep (regular expression file search tool) project. Information about the project can be found at https://www.gnu.org/software/grep/. If you have a bug report for this manual page, send it to bug-grep@gnu.org. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/grep.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-09-14.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU grep 3.11.21-102b-dirty 2019-12-29 GREP(1) Pages that refer to this page: look(1), pmrep(1), sed(1), regex(3), regex(7), bridge(8), ip(8), tc(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. file(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training file(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | ENVIRONMENT | FILES | EXIT STATUS | EXAMPLES | SEE ALSO | STANDARDS CONFORMANCE | SECURITY | MAGIC DIRECTORY | HISTORY | LEGAL NOTICE | BUGS | TODO | AVAILABILITY | COLOPHON FILE(1) General Commands Manual FILE(1) NAME top file determine file type SYNOPSIS top [-bcdEhiklLNnprsSvzZ0] [--apple] [--exclude-quiet] [--extension] [--mime-encoding] [--mime-type] [-e testname] [-F separator] [-f namefile] [-m magicfiles] [-P name=value] file ... -C [-m magicfiles] [--help] DESCRIPTION top This manual page documents version 5.45 of the command. tests each argument in an attempt to classify it. There are three sets of tests, performed in this order: filesystem tests, magic tests, and language tests. The first test that succeeds causes the file type to be printed. The type printed will usually contain one of the words text (the file contains only printing characters and a few common control characters and is probably safe to read on an ASCII terminal), executable (the file contains the result of compiling a program in a form understandable to some UNIX kernel or another), or data meaning anything else (data is usually binary or non- printable). Exceptions are well-known file formats (core files, tar archives) that are known to contain binary data. When modifying magic files or the program itself, make sure to preserve these keywords. Users depend on knowing that all the readable files in a directory have the word text printed. Don't do as Berkeley did and change shell commands text to shell script. The filesystem tests are based on examining the return from a stat(2) system call. The program checks to see if the file is empty, or if it's some sort of special file. Any known file types appropriate to the system you are running on (sockets, symbolic links, or named pipes (FIFOs) on those systems that implement them) are intuited if they are defined in the system header file <sys/stat.h>. The magic tests are used to check for files with data in particular fixed formats. The canonical example of this is a binary executable (compiled program) a.out file, whose format is defined in <elf.h>, <a.out.h> and possibly <exec.h> in the standard include directory. These files have a magic number stored in a particular place near the beginning of the file that tells the UNIX operating system that the file is a binary executable, and which of several types thereof. The concept of a magic number has been applied by extension to data files. Any file with some invariant identifier at a small fixed offset into the file can usually be described in this way. The information identifying these files is read from the compiled magic file /usr/local/share/misc/magic.mgc, or the files in the directory /usr/local/share/misc/magic if the compiled file does not exist. In addition, if $HOME/.magic.mgc or $HOME/.magic exists, it will be used in preference to the system magic files. If a file does not match any of the entries in the magic file, it is examined to see if it seems to be a text file. ASCII, ISO-8859-x, non-ISO 8-bit extended-ASCII character sets (such as those used on Macintosh and IBM PC systems), UTF-8-encoded Unicode, UTF-16-encoded Unicode, and EBCDIC character sets can be distinguished by the different ranges and sequences of bytes that constitute printable text in each set. If a file passes any of these tests, its character set is reported. ASCII, ISO-8859-x, UTF-8, and extended-ASCII files are identified as text because they will be mostly readable on nearly any terminal; UTF-16 and EBCDIC are only character data because, while they contain text, it is text that will require translation before it can be read. In addition, will attempt to determine other characteristics of text-type files. If the lines of a file are terminated by CR, CRLF, or NEL, instead of the Unix-standard LF, this will be reported. Files that contain embedded escape sequences or overstriking will also be identified. Once has determined the character set used in a text-type file, it will attempt to determine in what language the file is written. The language tests look for particular strings (cf. <names.h>) that can appear anywhere in the first few blocks of a file. For example, the keyword .br indicates that the file is most likely a troff(1) input file, just as the keyword struct indicates a C program. These tests are less reliable than the previous two groups, so they are performed last. The language test routines also test for some miscellany (such as tar(1) archives, JSON files). Any file that cannot be identified as having been written in any of the character sets listed above is simply said to be data. OPTIONS top --apple Causes the command to output the file type and creator code as used by older MacOS versions. The code consists of eight letters, the first describing the file type, the latter the creator. This option works properly only for file formats that have the apple-style output defined. -b, --brief Do not prepend filenames to output lines (brief mode). -C, --compile Write a magic.mgc output file that contains a pre-parsed version of the magic file or directory. -c, --checking-printout Cause a checking printout of the parsed form of the magic file. This is usually used in conjunction with the -m option to debug a new magic file before installing it. -d Prints internal debugging information to stderr. -E On filesystem errors (file not found etc), instead of handling the error as regular output as POSIX mandates and keep going, issue an error message and exit. -e, --exclude testname Exclude the test named in testname from the list of tests made to determine the file type. Valid test names are: apptype EMX application type (only on EMX). ascii Various types of text files (this test will try to guess the text encoding, irrespective of the setting of the encoding option). encoding Different text encodings for soft magic tests. tokens Ignored for backwards compatibility. cdf Prints details of Compound Document Files. compress Checks for, and looks inside, compressed files. csv Checks Comma Separated Value files. elf Prints ELF file details, provided soft magic tests are enabled and the elf magic is found. json Examines JSON (RFC-7159) files by parsing them for compliance. soft Consults magic files. simh Examines SIMH tape files. tar Examines tar files by verifying the checksum of the 512 byte tar header. Excluding this test can provide more detailed content description by using the soft magic method. text A synonym for ascii. --exclude-quiet Like --exclude but ignore tests that does not know about. This is intended for compatibility with older versions of . --extension Print a slash-separated list of valid extensions for the file type found. -F, --separator separator Use the specified string as the separator between the filename and the file result returned. Defaults to :. -f, --files-from namefile Read the names of the files to be examined from namefile (one per line) before the argument list. Either namefile or at least one filename argument must be present; to test the standard input, use - as a filename argument. Please note that namefile is unwrapped and the enclosed filenames are processed when this option is encountered and before any further options processing is done. This allows one to process multiple lists of files with different command line arguments on the same invocation. Thus if you want to set the delimiter, you need to do it before you specify the list of files, like: -F @ -f namefile, instead of: -f namefile -F @. -h, --no-dereference This option causes symlinks not to be followed (on systems that support symbolic links). This is the default if the environment variable POSIXLY_CORRECT is not defined. -i, --mime Causes the command to output mime type strings rather than the more traditional human readable ones. Thus it may say text/plain; charset=us-ascii rather than ASCII text. --mime-type, --mime-encoding Like -i, but print only the specified element(s). -k, --keep-going Don't stop at the first match, keep going. Subsequent matches will be have the string \012- prepended. (If you want a newline, see the -r option.) The magic pattern with the highest strength (see the -l option) comes first. -l, --list Shows a list of patterns and their strength sorted descending by magic(4) strength which is used for the matching (see also the -k option). -L, --dereference This option causes symlinks to be followed, as the like- named option in ls(1) (on systems that support symbolic links). This is the default if the environment variable POSIXLY_CORRECT is defined. -m, --magic-file magicfiles Specify an alternate list of files and directories containing magic. This can be a single item, or a colon- separated list. If a compiled magic file is found alongside a file or directory, it will be used instead. -N, --no-pad Don't pad filenames so that they align in the output. -n, --no-buffer Force stdout to be flushed after checking each file. This is only useful if checking a list of files. It is intended to be used by programs that want filetype output from a pipe. -p, --preserve-date On systems that support utime(3) or utimes(2), attempt to preserve the access time of files analyzed, to pretend that never read them. -P, --parameter name=value Set various parameter limits. Name Default Explanation bytes 1M max number of bytes to read from file elf_notes 256 max ELF notes processed elf_phnum 2K max ELF program sections processed elf_shnum 32K max ELF sections processed elf_shsize 128MB max ELF section size processed encoding 65K max number of bytes to determine encoding indir 50 recursion limit for indirect magic name 50 use count limit for name/use magic regex 8K length limit for regex searches -r, --raw Don't translate unprintable characters to \ooo. Normally translates unprintable characters to their octal representation. -s, --special-files Normally, only attempts to read and determine the type of argument files which stat(2) reports are ordinary files. This prevents problems, because reading special files may have peculiar consequences. Specifying the -s option causes to also read argument files which are block or character special files. This is useful for determining the filesystem types of the data in raw disk partitions, which are block special files. This option also causes to disregard the file size as reported by stat(2) since on some systems it reports a zero size for raw disk partitions. -S, --no-sandbox On systems where libseccomp (https://github.com/seccomp/libseccomp ) is available, the -S option disables sandboxing which is enabled by default. This option is needed for to execute external decompressing programs, i.e. when the -z option is specified and the built-in decompressors are not available. On systems where sandboxing is not available, this option has no effect. -v, --version Print the version of the program and exit. -z, --uncompress Try to look inside compressed files. -Z, --uncompress-noreport Try to look inside compressed files, but report information about the contents only not the compression. -0, --print0 Output a null character \0 after the end of the filename. Nice to cut(1) the output. This does not affect the separator, which is still printed. If this option is repeated more than once, then prints just the filename followed by a NUL followed by the description (or ERROR: text) followed by a second NUL for each entry. --help Print a help message and exit. ENVIRONMENT top The environment variable MAGIC can be used to set the default magic file name. If that variable is set, then will not attempt to open $HOME/.magic. adds .mgc to the value of this variable as appropriate. The environment variable POSIXLY_CORRECT controls (on systems that support symbolic links), whether will attempt to follow symlinks or not. If set, then follows symlink, otherwise it does not. This is also controlled by the -L and -h options. FILES top /usr/local/share/misc/magic.mgc Default compiled list of magic. /usr/local/share/misc/magic Directory containing default magic files. EXIT STATUS top will exit with 0 if the operation was successful or >0 if an error was encountered. The following errors cause diagnostic messages, but don't affect the program exit code (as POSIX requires), unless -E is specified: A file cannot be found There is no permission to read a file The file type cannot be determined EXAMPLES top $ file file.c file /dev/{wd0a,hda} file.c: C program text file: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked (uses shared libs), stripped /dev/wd0a: block special (0/0) /dev/hda: block special (3/0) $ file -s /dev/wd0{b,d} /dev/wd0b: data /dev/wd0d: x86 boot sector $ file -s /dev/hda{,1,2,3,4,5,6,7,8,9,10} /dev/hda: x86 boot sector /dev/hda1: Linux/i386 ext2 filesystem /dev/hda2: x86 boot sector /dev/hda3: x86 boot sector, extended partition table /dev/hda4: Linux/i386 ext2 filesystem /dev/hda5: Linux/i386 swap file /dev/hda6: Linux/i386 swap file /dev/hda7: Linux/i386 swap file /dev/hda8: Linux/i386 swap file /dev/hda9: empty /dev/hda10: empty $ file -i file.c file /dev/{wd0a,hda} file.c: text/x-c file: application/x-executable /dev/hda: application/x-not-regular-file /dev/wd0a: application/x-not-regular-file SEE ALSO top hexdump(1), od(1), strings(1), magic(4) STANDARDS CONFORMANCE top This program is believed to exceed the System V Interface Definition of FILE(CMD), as near as one can determine from the vague language contained therein. Its behavior is mostly compatible with the System V program of the same name. This version knows more magic, however, so it will produce different (albeit more accurate) output in many cases. The one significant difference between this version and System V is that this version treats any white space as a delimiter, so that spaces in pattern strings must be escaped. For example, >10 string language impress (imPRESS data) in an existing magic file would have to be changed to >10 string language\ impress (imPRESS data) In addition, in this version, if a pattern string contains a backslash, it must be escaped. For example 0 string \begindata Andrew Toolkit document in an existing magic file would have to be changed to 0 string \\begindata Andrew Toolkit document SunOS releases 3.2 and later from Sun Microsystems include a command derived from the System V one, but with some extensions. This version differs from Sun's only in minor ways. It includes the extension of the & operator, used as, for example, >16 long&0x7fffffff >0 not stripped SECURITY top On systems where libseccomp (https://github.com/seccomp/libseccomp ) is available, is enforces limiting system calls to only the ones necessary for the operation of the program. This enforcement does not provide any security benefit when is asked to decompress input files running external programs with the -z option. To enable execution of external decompressors, one needs to disable sandboxing using the -S option. MAGIC DIRECTORY top The magic file entries have been collected from various sources, mainly USENET, and contributed by various authors. Christos Zoulas (address below) will collect additional or corrected magic file entries. A consolidation of magic file entries will be distributed periodically. The order of entries in the magic file is significant. Depending on what system you are using, the order that they are put together may be incorrect. If your old command uses a magic file, keep the old magic file around for comparison purposes (rename it to /usr/local/share/misc/magic.orig). HISTORY top There has been a command in every UNIX since at least Research Version 4 (man page dated November, 1973). The System V version introduced one significant major change: the external list of magic types. This slowed the program down slightly but made it a lot more flexible. This program, based on the System V version, was written by Ian Darwin ian@darwinsys.com without looking at anybody else's source code. John Gilmore revised the code extensively, making it better than the first version. Geoff Collyer found several inadequacies and provided some magic file entries. Contributions of the & operator by Rob McMahon, cudcv@warwick.ac.uk, 1989. Guy Harris, guy@netapp.com, made many changes from 1993 to the present. Primary development and maintenance from 1990 to the present by Christos Zoulas christos@astron.com. Altered by Chris Lowth chris@lowth.com, 2000: handle the -i option to output mime type strings, using an alternative magic file and internal logic. Altered by Eric Fischer enf@pobox.com, July, 2000, to identify character codes and attempt to identify the languages of non- ASCII files. Altered by Reuben Thomas rrt@sc3d.org, 2007-2011, to improve MIME support, merge MIME and non-MIME magic, support directories as well as files of magic, apply many bug fixes, update and fix a lot of magic, improve the build system, improve the documentation, and rewrite the Python bindings in pure Python. The list of contributors to the magic directory (magic files) is too long to include here. You know who you are; thank you. Many contributors are listed in the source files. LEGAL NOTICE top Copyright (c) Ian F. Darwin, Toronto, Canada, 1986-1999. Covered by the standard Berkeley Software Distribution copyright; see the file COPYING in the source distribution. The files tar.h and is_tar.c were written by John Gilmore from his public-domain tar(1) program, and are not covered by the above license. BUGS top Please report bugs and send patches to the bug tracker at https://bugs.astron.com/ or the mailing list at file@astron.com (visit https://mailman.astron.com/mailman/listinfo/file first to subscribe). TODO top Fix output so that tests for MIME and APPLE flags are not needed all over the place, and actual output is only done in one place. This needs a design. Suggestion: push possible outputs on to a list, then pick the last-pushed (most specific, one hopes) value at the end, or use a default if the list is empty. This should not slow down evaluation. The handling of MAGIC_CONTINUE and printing \012- between entries is clumsy and complicated; refactor and centralize. Some of the encoding logic is hard-coded in encoding.c and can be moved to the magic files if we had a !:charset annotation. Continue to squash all magic bugs. See Debian BTS for a good source. Store arbitrarily long strings, for example for %s patterns, so that they can be printed out. Fixes Debian bug #271672. This can be done by allocating strings in a string pool, storing the string pool at the end of the magic file and converting all the string pointers to relative offsets from the string pool. Add syntax for relative offsets after current level (Debian bug #466037). Make file -ki work, i.e. give multiple MIME types. Add a zip library so we can peek inside Office2007 documents to print more details about their contents. Add an option to print URLs for the sources of the file descriptions. Combine script searches and add a way to map executable names to MIME types (e.g. have a magic value for !:mime which causes the resulting string to be looked up in a table). This would avoid adding the same magic repeatedly for each new hash-bang interpreter. When a file descriptor is available, we can skip and adjust the buffer instead of the hacky buffer management we do now. Fix name and use to check for consistency at compile time (duplicate name, use pointing to undefined name ). Make name / use more efficient by keeping a sorted list of names. Special-case ^ to flip endianness in the parser so that it does not have to be escaped, and document it. If the offsets specified internally in the file exceed the buffer size ( HOWMANY variable in file.h), then we don't seek to that offset, but we give up. It would be better if buffer managements was done when the file descriptor is available so we can seek around the file. One must be careful though because this has performance and thus security considerations, because one can slow down things by repeatedly seeking. There is support now for keeping separate buffers and having offsets from the end of the file, but the internal buffer management still needs an overhaul. AVAILABILITY top You can obtain the original author's latest version by anonymous FTP on ftp.astron.com in the directory /pub/file/file-X.YZ.tar.gz. COLOPHON top This page is part of the file (a file type guesser) project. Information about the project can be found at http://www.darwinsys.com/file/. If you have a bug report for this manual page, see http://bugs.gw.com/my_view_page.php. This page was obtained from the project's upstream Git read-only mirror of the CVS repository https://github.com/glensc/file on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-12-21.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU May 21, 2023 FILE(1) Pages that refer to this page: dh_installmanpages(1), dh_strip(1), ippeveprinter(1), pmcd(1), scr_dump(5), term(5), suffixes(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Decompress "path/to/test/file.gz" to standard output and save all lines matching "my regex" to files with a 1000000 line limit Bash Command:<START>gzip -dc path/to/test/file.gz | grep -P --regexp='my regex' | split -dl1000000 - file<END>

Decompress "path/to/test/file.gz" to standard output and save all lines matching "my regex" to files with a 1000000 line limit

gzip -dc path/to/test/file.gz | grep -P --regexp='my regex' | split -l1000000

['split', 'grep']

Output a Bash command to accomplish the following task. Task: Decompress "path/to/test/file.gz" to standard output and save all lines matching "my regex" to files with a 1000000 line limit Bash Command:<START>gzip -dc path/to/test/file.gz | grep -P --regexp='my regex' | split -l1000000<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # split\n\n> Split a file into pieces.\n> More information: <https://www.gnu.org/software/coreutils/split>.\n\n- Split a file, each split having 10 lines (except the last split):\n\n`split -l {{10}} {{path/to/file}}`\n\n- Split a file into 5 files. File is split such that each split has same size (except the last split):\n\n`split -n {{5}} {{path/to/file}}`\n\n- Split a file with 512 bytes in each split (except the last split; use 512k for kilobytes and 512m for megabytes):\n\n`split -b {{512}} {{path/to/file}}`\n\n- Split a file with at most 512 bytes in each split without breaking lines:\n\n`split -C {{512}} {{path/to/file}}`\n # grep\n\n> Find patterns in files using regular expressions.\n> More information: <https://www.gnu.org/software/grep/manual/grep.html>.\n\n- Search for a pattern within a file:\n\n`grep "{{search_pattern}}" {{path/to/file}}`\n\n- Search for an exact string (disables regular expressions):\n\n`grep --fixed-strings "{{exact_string}}" {{path/to/file}}`\n\n- Search for a pattern in all files recursively in a directory, showing line numbers of matches, ignoring binary files:\n\n`grep --recursive --line-number --binary-files={{without-match}} "{{search_pattern}}" {{path/to/directory}}`\n\n- Use extended regular expressions (supports `?`, `+`, `{}`, `()` and `|`), in case-insensitive mode:\n\n`grep --extended-regexp --ignore-case "{{search_pattern}}" {{path/to/file}}`\n\n- Print 3 lines of context around, before, or after each match:\n\n`grep --{{context|before-context|after-context}}={{3}} "{{search_pattern}}" {{path/to/file}}`\n\n- Print file name and line number for each match with color output:\n\n`grep --with-filename --line-number --color=always "{{search_pattern}}" {{path/to/file}}`\n\n- Search for lines matching a pattern, printing only the matched text:\n\n`grep --only-matching "{{search_pattern}}" {{path/to/file}}`\n\n- Search `stdin` for lines that do not match a pattern:\n\n`cat {{path/to/file}} | grep --invert-match "{{search_pattern}}"`\n Task: Decompress "path/to/test/file.gz" to standard output and save all lines matching "my regex" to files with a 1000000 line limit Bash Command:<START>gzip -dc path/to/test/file.gz | grep -P --regexp='my regex' | split -l1000000<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: split(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training split(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON SPLIT(1) User Commands SPLIT(1) NAME top split - split a file into pieces SYNOPSIS top split [OPTION]... [FILE [PREFIX]] DESCRIPTION top Output pieces of FILE to PREFIXaa, PREFIXab, ...; default size is 1000 lines, and default PREFIX is 'x'. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -a, --suffix-length=N generate suffixes of length N (default 2) --additional-suffix=SUFFIX append an additional SUFFIX to file names -b, --bytes=SIZE put SIZE bytes per output file -C, --line-bytes=SIZE put at most SIZE bytes of records per output file -d use numeric suffixes starting at 0, not alphabetic --numeric-suffixes[=FROM] same as -d, but allow setting the start value -x use hex suffixes starting at 0, not alphabetic --hex-suffixes[=FROM] same as -x, but allow setting the start value -e, --elide-empty-files do not generate empty output files with '-n' --filter=COMMAND write to shell COMMAND; file name is $FILE -l, --lines=NUMBER put NUMBER lines/records per output file -n, --number=CHUNKS generate CHUNKS output files; see explanation below -t, --separator=SEP use SEP instead of newline as the record separator; '\0' (zero) specifies the NUL character -u, --unbuffered immediately copy input to output with '-n r/...' --verbose print a diagnostic just before each output file is opened --help display this help and exit --version output version information and exit The SIZE argument is an integer and optional unit (example: 10K is 10*1024). Units are K,M,G,T,P,E,Z,Y,R,Q (powers of 1024) or KB,MB,... (powers of 1000). Binary prefixes can be used, too: KiB=K, MiB=M, and so on. CHUNKS may be: N split into N files based on size of input K/N output Kth of N to stdout l/N split into N files without splitting lines/records l/K/N output Kth of N to stdout without splitting lines/records r/N like 'l' but use round robin distribution r/K/N likewise but only output Kth of N to stdout AUTHOR top Written by Torbjorn Granlund and Richard M. Stallman. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top Full documentation <https://www.gnu.org/software/coreutils/split> or available locally via: info '(coreutils) split invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 SPLIT(1) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. grep(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training grep(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | REGULAR EXPRESSIONS | EXIT STATUS | ENVIRONMENT | NOTES | COPYRIGHT | BUGS | EXAMPLE | SEE ALSO | COLOPHON GREP(1) User Commands GREP(1) NAME top grep - print lines that match patterns SYNOPSIS top grep [OPTION...] PATTERNS [FILE...] grep [OPTION...] -e PATTERNS ... [FILE...] grep [OPTION...] -f PATTERN_FILE ... [FILE...] DESCRIPTION top grep searches for PATTERNS in each FILE. PATTERNS is one or more patterns separated by newline characters, and grep prints each line that matches a pattern. Typically PATTERNS should be quoted when grep is used in a shell command. A FILE of - stands for standard input. If no FILE is given, recursive searches examine the working directory, and nonrecursive searches read standard input. OPTIONS top Generic Program Information --help Output a usage message and exit. -V, --version Output the version number of grep and exit. Pattern Syntax -E, --extended-regexp Interpret PATTERNS as extended regular expressions (EREs, see below). -F, --fixed-strings Interpret PATTERNS as fixed strings, not regular expressions. -G, --basic-regexp Interpret PATTERNS as basic regular expressions (BREs, see below). This is the default. -P, --perl-regexp Interpret PATTERNS as Perl-compatible regular expressions (PCREs). This option is experimental when combined with the -z (--null-data) option, and grep -P may warn of unimplemented features. Matching Control -e PATTERNS, --regexp=PATTERNS Use PATTERNS as the patterns. If this option is used multiple times or is combined with the -f (--file) option, search for all patterns given. This option can be used to protect a pattern beginning with -. -f FILE, --file=FILE Obtain patterns from FILE, one per line. If this option is used multiple times or is combined with the -e (--regexp) option, search for all patterns given. The empty file contains zero patterns, and therefore matches nothing. If FILE is - , read patterns from standard input. -i, --ignore-case Ignore case distinctions in patterns and input data, so that characters that differ only in case match each other. --no-ignore-case Do not ignore case distinctions in patterns and input data. This is the default. This option is useful for passing to shell scripts that already use -i, to cancel its effects because the two options override each other. -v, --invert-match Invert the sense of matching, to select non-matching lines. -w, --word-regexp Select only those lines containing matches that form whole words. The test is that the matching substring must either be at the beginning of the line, or preceded by a non-word constituent character. Similarly, it must be either at the end of the line or followed by a non-word constituent character. Word-constituent characters are letters, digits, and the underscore. This option has no effect if -x is also specified. -x, --line-regexp Select only those matches that exactly match the whole line. For a regular expression pattern, this is like parenthesizing the pattern and then surrounding it with ^ and $. General Output Control -c, --count Suppress normal output; instead print a count of matching lines for each input file. With the -v, --invert-match option (see above), count non-matching lines. --color[=WHEN], --colour[=WHEN] Surround the matched (non-empty) strings, matching lines, context lines, file names, line numbers, byte offsets, and separators (for fields and groups of context lines) with escape sequences to display them in color on the terminal. The colors are defined by the environment variable GREP_COLORS. WHEN is never, always, or auto. -L, --files-without-match Suppress normal output; instead print the name of each input file from which no output would normally have been printed. -l, --files-with-matches Suppress normal output; instead print the name of each input file from which output would normally have been printed. Scanning each input file stops upon first match. -m NUM, --max-count=NUM Stop reading a file after NUM matching lines. If NUM is zero, grep stops right away without reading input. A NUM of -1 is treated as infinity and grep does not stop; this is the default. If the input is standard input from a regular file, and NUM matching lines are output, grep ensures that the standard input is positioned to just after the last matching line before exiting, regardless of the presence of trailing context lines. This enables a calling process to resume a search. When grep stops after NUM matching lines, it outputs any trailing context lines. When the -c or --count option is also used, grep does not output a count greater than NUM. When the -v or --invert-match option is also used, grep stops after outputting NUM non-matching lines. -o, --only-matching Print only the matched (non-empty) parts of a matching line, with each such part on a separate output line. -q, --quiet, --silent Quiet; do not write anything to standard output. Exit immediately with zero status if any match is found, even if an error was detected. Also see the -s or --no-messages option. -s, --no-messages Suppress error messages about nonexistent or unreadable files. Output Line Prefix Control -b, --byte-offset Print the 0-based byte offset within the input file before each line of output. If -o (--only-matching) is specified, print the offset of the matching part itself. -H, --with-filename Print the file name for each match. This is the default when there is more than one file to search. This is a GNU extension. -h, --no-filename Suppress the prefixing of file names on output. This is the default when there is only one file (or only standard input) to search. --label=LABEL Display input actually coming from standard input as input coming from file LABEL. This can be useful for commands that transform a file's contents before searching, e.g., gzip -cd foo.gz | grep --label=foo -H 'some pattern'. See also the -H option. -n, --line-number Prefix each line of output with the 1-based line number within its input file. -T, --initial-tab Make sure that the first character of actual line content lies on a tab stop, so that the alignment of tabs looks normal. This is useful with options that prefix their output to the actual content: -H,-n, and -b. In order to improve the probability that lines from a single file will all start at the same column, this also causes the line number and byte offset (if present) to be printed in a minimum size field width. -Z, --null Output a zero byte (the ASCII NUL character) instead of the character that normally follows a file name. For example, grep -lZ outputs a zero byte after each file name instead of the usual newline. This option makes the output unambiguous, even in the presence of file names containing unusual characters like newlines. This option can be used with commands like find -print0, perl -0, sort -z, and xargs -0 to process arbitrary file names, even those that contain newline characters. Context Line Control -A NUM, --after-context=NUM Print NUM lines of trailing context after matching lines. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. -B NUM, --before-context=NUM Print NUM lines of leading context before matching lines. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. -C NUM, -NUM, --context=NUM Print NUM lines of output context. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. --group-separator=SEP When -A, -B, or -C are in use, print SEP instead of -- between groups of lines. --no-group-separator When -A, -B, or -C are in use, do not print a separator between groups of lines. File and Directory Selection -a, --text Process a binary file as if it were text; this is equivalent to the --binary-files=text option. --binary-files=TYPE If a file's data or metadata indicate that the file contains binary data, assume that the file is of type TYPE. Non-text bytes indicate binary data; these are either output bytes that are improperly encoded for the current locale, or null input bytes when the -z option is not given. By default, TYPE is binary, and grep suppresses output after null input binary data is discovered, and suppresses output lines that contain improperly encoded data. When some output is suppressed, grep follows any output with a message to standard error saying that a binary file matches. If TYPE is without-match, when grep discovers null input binary data it assumes that the rest of the file does not match; this is equivalent to the -I option. If TYPE is text, grep processes a binary file as if it were text; this is equivalent to the -a option. When type is binary, grep may treat non-text bytes as line terminators even without the -z option. This means choosing binary versus text can affect whether a pattern matches a file. For example, when type is binary the pattern q$ might match q immediately followed by a null byte, even though this is not matched when type is text. Conversely, when type is binary the pattern . (period) might not match a null byte. Warning: The -a option might output binary garbage, which can have nasty side effects if the output is a terminal and if the terminal driver interprets some of it as commands. On the other hand, when reading files whose text encodings are unknown, it can be helpful to use -a or to set LC_ALL='C' in the environment, in order to find more matches even if the matches are unsafe for direct display. -D ACTION, --devices=ACTION If an input file is a device, FIFO or socket, use ACTION to process it. By default, ACTION is read, which means that devices are read just as if they were ordinary files. If ACTION is skip, devices are silently skipped. -d ACTION, --directories=ACTION If an input file is a directory, use ACTION to process it. By default, ACTION is read, i.e., read directories just as if they were ordinary files. If ACTION is skip, silently skip directories. If ACTION is recurse, read all files under each directory, recursively, following symbolic links only if they are on the command line. This is equivalent to the -r option. --exclude=GLOB Skip any command-line file with a name suffix that matches the pattern GLOB, using wildcard matching; a name suffix is either the whole name, or a trailing part that starts with a non-slash character immediately after a slash (/) in the name. When searching recursively, skip any subfile whose base name matches GLOB; the base name is the part after the last slash. A pattern can use *, ?, and [...] as wildcards, and \ to quote a wildcard or backslash character literally. --exclude-from=FILE Skip files whose base name matches any of the file-name globs read from FILE (using wildcard matching as described under --exclude). --exclude-dir=GLOB Skip any command-line directory with a name suffix that matches the pattern GLOB. When searching recursively, skip any subdirectory whose base name matches GLOB. Ignore any redundant trailing slashes in GLOB. -I Process a binary file as if it did not contain matching data; this is equivalent to the --binary-files=without-match option. --include=GLOB Search only files whose base name matches GLOB (using wildcard matching as described under --exclude). If contradictory --include and --exclude options are given, the last matching one wins. If no --include or --exclude options match, a file is included unless the first such option is --include. -r, --recursive Read all files under each directory, recursively, following symbolic links only if they are on the command line. Note that if no file operand is given, grep searches the working directory. This is equivalent to the -d recurse option. -R, --dereference-recursive Read all files under each directory, recursively. Follow all symbolic links, unlike -r. Other Options --line-buffered Use line buffering on output. This can cause a performance penalty. -U, --binary Treat the file(s) as binary. By default, under MS-DOS and MS-Windows, grep guesses whether a file is text or binary as described for the --binary-files option. If grep decides the file is a text file, it strips the CR characters from the original file contents (to make regular expressions with ^ and $ work correctly). Specifying -U overrules this guesswork, causing all files to be read and passed to the matching mechanism verbatim; if the file is a text file with CR/LF pairs at the end of each line, this will cause some regular expressions to fail. This option has no effect on platforms other than MS-DOS and MS-Windows. -z, --null-data Treat input and output data as sequences of lines, each terminated by a zero byte (the ASCII NUL character) instead of a newline. Like the -Z or --null option, this option can be used with commands like sort -z to process arbitrary file names. REGULAR EXPRESSIONS top A regular expression is a pattern that describes a set of strings. Regular expressions are constructed analogously to arithmetic expressions, by using various operators to combine smaller expressions. grep understands three different versions of regular expression syntax: basic (BRE), extended (ERE) and perl (PCRE). In GNU grep, basic and extended regular expressions are merely different notations for the same pattern-matching functionality. In other implementations, basic regular expressions are ordinarily less powerful than extended, though occasionally it is the other way around. The following description applies to extended regular expressions; differences for basic regular expressions are summarized afterwards. Perl-compatible regular expressions have different functionality, and are documented in pcre2syntax(3) and pcre2pattern(3), but work only if PCRE support is enabled. The fundamental building blocks are the regular expressions that match a single character. Most characters, including all letters and digits, are regular expressions that match themselves. Any meta-character with special meaning may be quoted by preceding it with a backslash. The period . matches any single character. It is unspecified whether it matches an encoding error. Character Classes and Bracket Expressions A bracket expression is a list of characters enclosed by [ and ]. It matches any single character in that list. If the first character of the list is the caret ^ then it matches any character not in the list; it is unspecified whether it matches an encoding error. For example, the regular expression [0123456789] matches any single digit. Within a bracket expression, a range expression consists of two characters separated by a hyphen. It matches any single character that sorts between the two characters, inclusive, using the locale's collating sequence and character set. For example, in the default C locale, [a-d] is equivalent to [abcd]. Many locales sort characters in dictionary order, and in these locales [a-d] is typically not equivalent to [abcd]; it might be equivalent to [aBbCcDd], for example. To obtain the traditional interpretation of bracket expressions, you can use the C locale by setting the LC_ALL environment variable to the value C. Finally, certain named classes of characters are predefined within bracket expressions, as follows. Their names are self explanatory, and they are [:alnum:], [:alpha:], [:blank:], [:cntrl:], [:digit:], [:graph:], [:lower:], [:print:], [:punct:], [:space:], [:upper:], and [:xdigit:]. For example, [[:alnum:]] means the character class of numbers and letters in the current locale. In the C locale and ASCII character set encoding, this is the same as [0-9A-Za-z]. (Note that the brackets in these class names are part of the symbolic names, and must be included in addition to the brackets delimiting the bracket expression.) Most meta-characters lose their special meaning inside bracket expressions. To include a literal ] place it first in the list. Similarly, to include a literal ^ place it anywhere but first. Finally, to include a literal - place it last. Anchoring The caret ^ and the dollar sign $ are meta-characters that respectively match the empty string at the beginning and end of a line. The Backslash Character and Special Expressions The symbols \< and \> respectively match the empty string at the beginning and end of a word. The symbol \b matches the empty string at the edge of a word, and \B matches the empty string provided it's not at the edge of a word. The symbol \w is a synonym for [_[:alnum:]] and \W is a synonym for [^_[:alnum:]]. Repetition A regular expression may be followed by one of several repetition operators: ? The preceding item is optional and matched at most once. * The preceding item will be matched zero or more times. + The preceding item will be matched one or more times. {n} The preceding item is matched exactly n times. {n,} The preceding item is matched n or more times. {,m} The preceding item is matched at most m times. This is a GNU extension. {n,m} The preceding item is matched at least n times, but not more than m times. Concatenation Two regular expressions may be concatenated; the resulting regular expression matches any string formed by concatenating two substrings that respectively match the concatenated expressions. Alternation Two regular expressions may be joined by the infix operator |; the resulting regular expression matches any string matching either alternate expression. Precedence Repetition takes precedence over concatenation, which in turn takes precedence over alternation. A whole expression may be enclosed in parentheses to override these precedence rules and form a subexpression. Back-references and Subexpressions The back-reference \n, where n is a single digit, matches the substring previously matched by the nth parenthesized subexpression of the regular expression. Basic vs Extended Regular Expressions In basic regular expressions the meta-characters ?, +, {, |, (, and ) lose their special meaning; instead use the backslashed versions \?, \+, \{, \|, \(, and \). EXIT STATUS top Normally the exit status is 0 if a line is selected, 1 if no lines were selected, and 2 if an error occurred. However, if the -q or --quiet or --silent is used and a line is selected, the exit status is 0 even if an error occurred. ENVIRONMENT top The behavior of grep is affected by the following environment variables. The locale for category LC_foo is specified by examining the three environment variables LC_ALL, LC_foo, LANG, in that order. The first of these variables that is set specifies the locale. For example, if LC_ALL is not set, but LC_MESSAGES is set to pt_BR, then the Brazilian Portuguese locale is used for the LC_MESSAGES category. The C locale is used if none of these environment variables are set, if the locale catalog is not installed, or if grep was not compiled with national language support (NLS). The shell command locale -a lists locales that are currently available. GREP_COLORS Controls how the --color option highlights output. Its value is a colon-separated list of capabilities that defaults to ms=01;31:mc=01;31:sl=:cx=:fn=35:ln=32:bn=32:se=36 with the rv and ne boolean capabilities omitted (i.e., false). Supported capabilities are as follows. sl= SGR substring for whole selected lines (i.e., matching lines when the -v command-line option is omitted, or non-matching lines when -v is specified). If however the boolean rv capability and the -v command-line option are both specified, it applies to context matching lines instead. The default is empty (i.e., the terminal's default color pair). cx= SGR substring for whole context lines (i.e., non- matching lines when the -v command-line option is omitted, or matching lines when -v is specified). If however the boolean rv capability and the -v command-line option are both specified, it applies to selected non-matching lines instead. The default is empty (i.e., the terminal's default color pair). rv Boolean value that reverses (swaps) the meanings of the sl= and cx= capabilities when the -v command- line option is specified. The default is false (i.e., the capability is omitted). mt=01;31 SGR substring for matching non-empty text in any matching line (i.e., a selected line when the -v command-line option is omitted, or a context line when -v is specified). Setting this is equivalent to setting both ms= and mc= at once to the same value. The default is a bold red text foreground over the current line background. ms=01;31 SGR substring for matching non-empty text in a selected line. (This is only used when the -v command-line option is omitted.) The effect of the sl= (or cx= if rv) capability remains active when this kicks in. The default is a bold red text foreground over the current line background. mc=01;31 SGR substring for matching non-empty text in a context line. (This is only used when the -v command-line option is specified.) The effect of the cx= (or sl= if rv) capability remains active when this kicks in. The default is a bold red text foreground over the current line background. fn=35 SGR substring for file names prefixing any content line. The default is a magenta text foreground over the terminal's default background. ln=32 SGR substring for line numbers prefixing any content line. The default is a green text foreground over the terminal's default background. bn=32 SGR substring for byte offsets prefixing any content line. The default is a green text foreground over the terminal's default background. se=36 SGR substring for separators that are inserted between selected line fields (:), between context line fields, (-), and between groups of adjacent lines when nonzero context is specified (--). The default is a cyan text foreground over the terminal's default background. ne Boolean value that prevents clearing to the end of line using Erase in Line (EL) to Right (\33[K) each time a colorized item ends. This is needed on terminals on which EL is not supported. It is otherwise useful on terminals for which the back_color_erase (bce) boolean terminfo capability does not apply, when the chosen highlight colors do not affect the background, or when EL is too slow or causes too much flicker. The default is false (i.e., the capability is omitted). Note that boolean capabilities have no =... part. They are omitted (i.e., false) by default and become true when specified. See the Select Graphic Rendition (SGR) section in the documentation of the text terminal that is used for permitted values and their meaning as character attributes. These substring values are integers in decimal representation and can be concatenated with semicolons. grep takes care of assembling the result into a complete SGR sequence (\33[...m). Common values to concatenate include 1 for bold, 4 for underline, 5 for blink, 7 for inverse, 39 for default foreground color, 30 to 37 for foreground colors, 90 to 97 for 16-color mode foreground colors, 38;5;0 to 38;5;255 for 88-color and 256-color modes foreground colors, 49 for default background color, 40 to 47 for background colors, 100 to 107 for 16-color mode background colors, and 48;5;0 to 48;5;255 for 88-color and 256-color modes background colors. LC_ALL, LC_COLLATE, LANG These variables specify the locale for the LC_COLLATE category, which determines the collating sequence used to interpret range expressions like [a-z]. LC_ALL, LC_CTYPE, LANG These variables specify the locale for the LC_CTYPE category, which determines the type of characters, e.g., which characters are whitespace. This category also determines the character encoding, that is, whether text is encoded in UTF-8, ASCII, or some other encoding. In the C or POSIX locale, all characters are encoded as a single byte and every byte is a valid character. LC_ALL, LC_MESSAGES, LANG These variables specify the locale for the LC_MESSAGES category, which determines the language that grep uses for messages. The default C locale uses American English messages. POSIXLY_CORRECT If set, grep behaves as POSIX requires; otherwise, grep behaves more like other GNU programs. POSIX requires that options that follow file names must be treated as file names; by default, such options are permuted to the front of the operand list and are treated as options. Also, POSIX requires that unrecognized options be diagnosed as illegal, but since they are not really against the law the default is to diagnose them as invalid. NOTES top This man page is maintained only fitfully; the full documentation is often more up-to-date. COPYRIGHT top Copyright 1998-2000, 2002, 2005-2023 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. BUGS top Reporting Bugs Email bug reports to the bug-reporting address bug- grep@gnu.org. An email archive https://lists.gnu.org/mailman/listinfo/bug-grep and a bug tracker https://debbugs.gnu.org/cgi/pkgreport.cgi?package=grep are available. Known Bugs Large repetition counts in the {n,m} construct may cause grep to use lots of memory. In addition, certain other obscure regular expressions require exponential time and space, and may cause grep to run out of memory. Back-references are very slow, and may require exponential time. EXAMPLE top The following example outputs the location and contents of any line containing f and ending in .c, within all files in the current directory whose names contain g and end in .h. The -n option outputs line numbers, the -- argument treats expansions of *g*.h starting with - as file names not options, and the empty file /dev/null causes file names to be output even if only one file name happens to be of the form *g*.h. $ grep -n -- 'f.*\.c$' *g*.h /dev/null argmatch.h:1:/* definitions and prototypes for argmatch.c The only line that matches is line 1 of argmatch.h. Note that the regular expression syntax used in the pattern differs from the globbing syntax that the shell uses to match file names. SEE ALSO top Regular Manual Pages awk(1), cmp(1), diff(1), find(1), perl(1), sed(1), sort(1), xargs(1), read(2), pcre2(3), pcre2syntax(3), pcre2pattern(3), terminfo(5), glob(7), regex(7) Full Documentation A complete manual https://www.gnu.org/software/grep/manual/ is available. If the info and grep programs are properly installed at your site, the command info grep should give you access to the complete manual. COLOPHON top This page is part of the GNU grep (regular expression file search tool) project. Information about the project can be found at https://www.gnu.org/software/grep/. If you have a bug report for this manual page, send it to bug-grep@gnu.org. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/grep.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-09-14.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU grep 3.11.21-102b-dirty 2019-12-29 GREP(1) Pages that refer to this page: look(1), pmrep(1), sed(1), regex(3), regex(7), bridge(8), ip(8), tc(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Decompress "path/to/test/file.gz" to standard output and save all lines matching "my regex" to files with a 1000000 line limit Bash Command:<START>gzip -dc path/to/test/file.gz | grep -P --regexp='my regex' | split -l1000000<END>

Decompress 'file.gz' to standard output and execute the output in bash

gzip -d --stdout file.gz | bash

['bash']

Output a Bash command to accomplish the following task. Task: Decompress 'file.gz' to standard output and execute the output in bash Bash Command:<START>gzip -d --stdout file.gz | bash<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # bash\n\n> Bourne-Again SHell, an `sh`-compatible command-line interpreter.\n> See also: `zsh`, `histexpand` (history expansion).\n> More information: <https://www.gnu.org/software/bash/>.\n\n- Start an interactive shell session:\n\n`bash`\n\n- Start an interactive shell session without loading startup configs:\n\n`bash --norc`\n\n- Execute specific [c]ommands:\n\n`bash -c "{{echo 'bash is executed'}}"`\n\n- Execute a specific script:\n\n`bash {{path/to/script.sh}}`\n\n- E[x]ecute a specific script, printing each command before executing it:\n\n`bash -x {{path/to/script.sh}}`\n\n- Execute a specific script and stop at the first [e]rror:\n\n`bash -e {{path/to/script.sh}}`\n\n- Execute specific commands from `stdin`:\n\n`{{echo "echo 'bash is executed'"}} | bash`\n\n- Start a [r]estricted shell session:\n\n`bash -r`\n Task: Decompress 'file.gz' to standard output and execute the output in bash Bash Command:<START>gzip -d --stdout file.gz | bash<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: bash(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training bash(1) Linux manual page NAME | SYNOPSIS | COPYRIGHT | DESCRIPTION | OPTIONS | ARGUMENTS | INVOCATION | DEFINITIONS | RESERVED WORDS | SHELL GRAMMAR | COMMENTS | QUOTING | PARAMETERS | EXPANSION | REDIRECTION | ALIASES | FUNCTIONS | ARITHMETIC EVALUATION | CONDITIONAL EXPRESSIONS | SIMPLE COMMAND EXPANSION | COMMAND EXECUTION | COMMAND EXECUTION ENVIRONMENT | ENVIRONMENT | EXIT STATUS | SIGNALS | JOB CONTROL | PROMPTING | READLINE | HISTORY | HISTORY EXPANSION | SHELL BUILTIN COMMANDS | SHELL COMPATIBILITY MODE | RESTRICTED SHELL | SEE ALSO | FILES | AUTHORS | BUG REPORTS | BUGS | COLOPHON BASH(1) General Commands Manual BASH(1) NAME top bash - GNU Bourne-Again SHell SYNOPSIS top bash [options] [command_string | file] COPYRIGHT top Bash is Copyright (C) 1989-2022 by the Free Software Foundation, Inc. DESCRIPTION top Bash is an sh-compatible command language interpreter that executes commands read from the standard input or from a file. Bash also incorporates useful features from the Korn and C shells (ksh and csh). Bash is intended to be a conformant implementation of the Shell and Utilities portion of the IEEE POSIX specification (IEEE Standard 1003.1). Bash can be configured to be POSIX-conformant by default. OPTIONS top All of the single-character shell options documented in the description of the set builtin command, including -o, can be used as options when the shell is invoked. In addition, bash interprets the following options when it is invoked: -c If the -c option is present, then commands are read from the first non-option argument command_string. If there are arguments after the command_string, the first argument is assigned to $0 and any remaining arguments are assigned to the positional parameters. The assignment to $0 sets the name of the shell, which is used in warning and error messages. -i If the -i option is present, the shell is interactive. -l Make bash act as if it had been invoked as a login shell (see INVOCATION below). -r If the -r option is present, the shell becomes restricted (see RESTRICTED SHELL below). -s If the -s option is present, or if no arguments remain after option processing, then commands are read from the standard input. This option allows the positional parameters to be set when invoking an interactive shell or when reading input through a pipe. -D A list of all double-quoted strings preceded by $ is printed on the standard output. These are the strings that are subject to language translation when the current locale is not C or POSIX. This implies the -n option; no commands will be executed. [-+]O [shopt_option] shopt_option is one of the shell options accepted by the shopt builtin (see SHELL BUILTIN COMMANDS below). If shopt_option is present, -O sets the value of that option; +O unsets it. If shopt_option is not supplied, the names and values of the shell options accepted by shopt are printed on the standard output. If the invocation option is +O, the output is displayed in a format that may be reused as input. -- A -- signals the end of options and disables further option processing. Any arguments after the -- are treated as filenames and arguments. An argument of - is equivalent to --. Bash also interprets a number of multi-character options. These options must appear on the command line before the single- character options to be recognized. --debugger Arrange for the debugger profile to be executed before the shell starts. Turns on extended debugging mode (see the description of the extdebug option to the shopt builtin below). --dump-po-strings Equivalent to -D, but the output is in the GNU gettext po (portable object) file format. --dump-strings Equivalent to -D. --help Display a usage message on standard output and exit successfully. --init-file file --rcfile file Execute commands from file instead of the standard personal initialization file ~/.bashrc if the shell is interactive (see INVOCATION below). --login Equivalent to -l. --noediting Do not use the GNU readline library to read command lines when the shell is interactive. --noprofile Do not read either the system-wide startup file /etc/profile or any of the personal initialization files ~/.bash_profile, ~/.bash_login, or ~/.profile. By default, bash reads these files when it is invoked as a login shell (see INVOCATION below). --norc Do not read and execute the personal initialization file ~/.bashrc if the shell is interactive. This option is on by default if the shell is invoked as sh. --posix Change the behavior of bash where the default operation differs from the POSIX standard to match the standard (posix mode). See SEE ALSO below for a reference to a document that details how posix mode affects bash's behavior. --restricted The shell becomes restricted (see RESTRICTED SHELL below). --verbose Equivalent to -v. --version Show version information for this instance of bash on the standard output and exit successfully. ARGUMENTS top If arguments remain after option processing, and neither the -c nor the -s option has been supplied, the first argument is assumed to be the name of a file containing shell commands. If bash is invoked in this fashion, $0 is set to the name of the file, and the positional parameters are set to the remaining arguments. Bash reads and executes commands from this file, then exits. Bash's exit status is the exit status of the last command executed in the script. If no commands are executed, the exit status is 0. An attempt is first made to open the file in the current directory, and, if no file is found, then the shell searches the directories in PATH for the script. INVOCATION top A login shell is one whose first character of argument zero is a -, or one started with the --login option. An interactive shell is one started without non-option arguments (unless -s is specified) and without the -c option, whose standard input and error are both connected to terminals (as determined by isatty(3)), or one started with the -i option. PS1 is set and $- includes i if bash is interactive, allowing a shell script or a startup file to test this state. The following paragraphs describe how bash executes its startup files. If any of the files exist but cannot be read, bash reports an error. Tildes are expanded in filenames as described below under Tilde Expansion in the EXPANSION section. When bash is invoked as an interactive login shell, or as a non- interactive shell with the --login option, it first reads and executes commands from the file /etc/profile, if that file exists. After reading that file, it looks for ~/.bash_profile, ~/.bash_login, and ~/.profile, in that order, and reads and executes commands from the first one that exists and is readable. The --noprofile option may be used when the shell is started to inhibit this behavior. When an interactive login shell exits, or a non-interactive login shell executes the exit builtin command, bash reads and executes commands from the file ~/.bash_logout, if it exists. When an interactive shell that is not a login shell is started, bash reads and executes commands from ~/.bashrc, if that file exists. This may be inhibited by using the --norc option. The --rcfile file option will force bash to read and execute commands from file instead of ~/.bashrc. When bash is started non-interactively, to run a shell script, for example, it looks for the variable BASH_ENV in the environment, expands its value if it appears there, and uses the expanded value as the name of a file to read and execute. Bash behaves as if the following command were executed: if [ -n "$BASH_ENV" ]; then . "$BASH_ENV"; fi but the value of the PATH variable is not used to search for the filename. If bash is invoked with the name sh, it tries to mimic the startup behavior of historical versions of sh as closely as possible, while conforming to the POSIX standard as well. When invoked as an interactive login shell, or a non-interactive shell with the --login option, it first attempts to read and execute commands from /etc/profile and ~/.profile, in that order. The --noprofile option may be used to inhibit this behavior. When invoked as an interactive shell with the name sh, bash looks for the variable ENV, expands its value if it is defined, and uses the expanded value as the name of a file to read and execute. Since a shell invoked as sh does not attempt to read and execute commands from any other startup files, the --rcfile option has no effect. A non-interactive shell invoked with the name sh does not attempt to read any other startup files. When invoked as sh, bash enters posix mode after the startup files are read. When bash is started in posix mode, as with the --posix command line option, it follows the POSIX standard for startup files. In this mode, interactive shells expand the ENV variable and commands are read and executed from the file whose name is the expanded value. No other startup files are read. Bash attempts to determine when it is being run with its standard input connected to a network connection, as when executed by the historical remote shell daemon, usually rshd, or the secure shell daemon sshd. If bash determines it is being run non- interactively in this fashion, it reads and executes commands from ~/.bashrc, if that file exists and is readable. It will not do this if invoked as sh. The --norc option may be used to inhibit this behavior, and the --rcfile option may be used to force another file to be read, but neither rshd nor sshd generally invoke the shell with those options or allow them to be specified. If the shell is started with the effective user (group) id not equal to the real user (group) id, and the -p option is not supplied, no startup files are read, shell functions are not inherited from the environment, the SHELLOPTS, BASHOPTS, CDPATH, and GLOBIGNORE variables, if they appear in the environment, are ignored, and the effective user id is set to the real user id. If the -p option is supplied at invocation, the startup behavior is the same, but the effective user id is not reset. DEFINITIONS top The following definitions are used throughout the rest of this document. blank A space or tab. word A sequence of characters considered as a single unit by the shell. Also known as a token. name A word consisting only of alphanumeric characters and underscores, and beginning with an alphabetic character or an underscore. Also referred to as an identifier. metacharacter A character that, when unquoted, separates words. One of the following: | & ; ( ) < > space tab newline control operator A token that performs a control function. It is one of the following symbols: || & && ; ;; ;& ;;& ( ) | |& <newline> RESERVED WORDS top Reserved words are words that have a special meaning to the shell. The following words are recognized as reserved when unquoted and either the first word of a command (see SHELL GRAMMAR below), the third word of a case or select command (only in is valid), or the third word of a for command (only in and do are valid): ! case coproc do done elif else esac fi for function if in select then until while { } time [[ ]] SHELL GRAMMAR top This section describes the syntax of the various forms of shell commands. Simple Commands A simple command is a sequence of optional variable assignments followed by blank-separated words and redirections, and terminated by a control operator. The first word specifies the command to be executed, and is passed as argument zero. The remaining words are passed as arguments to the invoked command. The return value of a simple command is its exit status, or 128+n if the command is terminated by signal n. Pipelines A pipeline is a sequence of one or more commands separated by one of the control operators | or |&. The format for a pipeline is: [time [-p]] [ ! ] command1 [ [||&] command2 ... ] The standard output of command1 is connected via a pipe to the standard input of command2. This connection is performed before any redirections specified by the command1(see REDIRECTION below). If |& is used, command1's standard error, in addition to its standard output, is connected to command2's standard input through the pipe; it is shorthand for 2>&1 |. This implicit redirection of the standard error to the standard output is performed after any redirections specified by command1. The return status of a pipeline is the exit status of the last command, unless the pipefail option is enabled. If pipefail is enabled, the pipeline's return status is the value of the last (rightmost) command to exit with a non-zero status, or zero if all commands exit successfully. If the reserved word ! precedes a pipeline, the exit status of that pipeline is the logical negation of the exit status as described above. The shell waits for all commands in the pipeline to terminate before returning a value. If the time reserved word precedes a pipeline, the elapsed as well as user and system time consumed by its execution are reported when the pipeline terminates. The -p option changes the output format to that specified by POSIX. When the shell is in posix mode, it does not recognize time as a reserved word if the next token begins with a `-'. The TIMEFORMAT variable may be set to a format string that specifies how the timing information should be displayed; see the description of TIMEFORMAT under Shell Variables below. When the shell is in posix mode, time may be followed by a newline. In this case, the shell displays the total user and system time consumed by the shell and its children. The TIMEFORMAT variable may be used to specify the format of the time information. Each command in a multi-command pipeline, where pipes are created, is executed in a subshell, which is a separate process. See COMMAND EXECUTION ENVIRONMENT for a description of subshells and a subshell environment. If the lastpipe option is enabled using the shopt builtin (see the description of shopt below), the last element of a pipeline may be run by the shell process when job control is not active. Lists A list is a sequence of one or more pipelines separated by one of the operators ;, &, &&, or ||, and optionally terminated by one of ;, &, or <newline>. Of these list operators, && and || have equal precedence, followed by ; and &, which have equal precedence. A sequence of one or more newlines may appear in a list instead of a semicolon to delimit commands. If a command is terminated by the control operator &, the shell executes the command in the background in a subshell. The shell does not wait for the command to finish, and the return status is 0. These are referred to as asynchronous commands. Commands separated by a ; are executed sequentially; the shell waits for each command to terminate in turn. The return status is the exit status of the last command executed. AND and OR lists are sequences of one or more pipelines separated by the && and || control operators, respectively. AND and OR lists are executed with left associativity. An AND list has the form command1 && command2 command2 is executed if, and only if, command1 returns an exit status of zero (success). An OR list has the form command1 || command2 command2 is executed if, and only if, command1 returns a non-zero exit status. The return status of AND and OR lists is the exit status of the last command executed in the list. Compound Commands A compound command is one of the following. In most cases a list in a command's description may be separated from the rest of the command by one or more newlines, and may be followed by a newline in place of a semicolon. (list) list is executed in a subshell (see COMMAND EXECUTION ENVIRONMENT below for a description of a subshell environment). Variable assignments and builtin commands that affect the shell's environment do not remain in effect after the command completes. The return status is the exit status of list. { list; } list is simply executed in the current shell environment. list must be terminated with a newline or semicolon. This is known as a group command. The return status is the exit status of list. Note that unlike the metacharacters ( and ), { and } are reserved words and must occur where a reserved word is permitted to be recognized. Since they do not cause a word break, they must be separated from list by whitespace or another shell metacharacter. ((expression)) The expression is evaluated according to the rules described below under ARITHMETIC EVALUATION. If the value of the expression is non-zero, the return status is 0; otherwise the return status is 1. The expression undergoes the same expansions as if it were within double quotes, but double quote characters in expression are not treated specially and are removed. [[ expression ]] Return a status of 0 or 1 depending on the evaluation of the conditional expression expression. Expressions are composed of the primaries described below under CONDITIONAL EXPRESSIONS. The words between the [[ and ]] do not undergo word splitting and pathname expansion. The shell performs tilde expansion, parameter and variable expansion, arithmetic expansion, command substitution, process substitution, and quote removal on those words (the expansions that would occur if the words were enclosed in double quotes). Conditional operators such as -f must be unquoted to be recognized as primaries. When used with [[, the < and > operators sort lexicographically using the current locale. When the == and != operators are used, the string to the right of the operator is considered a pattern and matched according to the rules described below under Pattern Matching, as if the extglob shell option were enabled. The = operator is equivalent to ==. If the nocasematch shell option is enabled, the match is performed without regard to the case of alphabetic characters. The return value is 0 if the string matches (==) or does not match (!=) the pattern, and 1 otherwise. Any part of the pattern may be quoted to force the quoted portion to be matched as a string. An additional binary operator, =~, is available, with the same precedence as == and !=. When it is used, the string to the right of the operator is considered a POSIX extended regular expression and matched accordingly (using the POSIX regcomp and regexec interfaces usually described in regex(3)). The return value is 0 if the string matches the pattern, and 1 otherwise. If the regular expression is syntactically incorrect, the conditional expression's return value is 2. If the nocasematch shell option is enabled, the match is performed without regard to the case of alphabetic characters. If any part of the pattern is quoted, the quoted portion is matched literally. This means every character in the quoted portion matches itself, instead of having any special pattern matching meaning. If the pattern is stored in a shell variable, quoting the variable expansion forces the entire pattern to be matched literally. Treat bracket expressions in regular expressions carefully, since normal quoting and pattern characters lose their meanings between brackets. The pattern will match if it matches any part of the string. Anchor the pattern using the ^ and $ regular expression operators to force it to match the entire string. The array variable BASH_REMATCH records which parts of the string matched the pattern. The element of BASH_REMATCH with index 0 contains the portion of the string matching the entire regular expression. Substrings matched by parenthesized subexpressions within the regular expression are saved in the remaining BASH_REMATCH indices. The element of BASH_REMATCH with index n is the portion of the string matching the nth parenthesized subexpression. Bash sets BASH_REMATCH in the global scope; declaring it as a local variable will lead to unexpected results. Expressions may be combined using the following operators, listed in decreasing order of precedence: ( expression ) Returns the value of expression. This may be used to override the normal precedence of operators. ! expression True if expression is false. expression1 && expression2 True if both expression1 and expression2 are true. expression1 || expression2 True if either expression1 or expression2 is true. The && and || operators do not evaluate expression2 if the value of expression1 is sufficient to determine the return value of the entire conditional expression. for name [ [ in [ word ... ] ] ; ] do list ; done The list of words following in is expanded, generating a list of items. The variable name is set to each element of this list in turn, and list is executed each time. If the in word is omitted, the for command executes list once for each positional parameter that is set (see PARAMETERS below). The return status is the exit status of the last command that executes. If the expansion of the items following in results in an empty list, no commands are executed, and the return status is 0. for (( expr1 ; expr2 ; expr3 )) ; do list ; done First, the arithmetic expression expr1 is evaluated according to the rules described below under ARITHMETIC EVALUATION. The arithmetic expression expr2 is then evaluated repeatedly until it evaluates to zero. Each time expr2 evaluates to a non-zero value, list is executed and the arithmetic expression expr3 is evaluated. If any expression is omitted, it behaves as if it evaluates to 1. The return value is the exit status of the last command in list that is executed, or false if any of the expressions is invalid. select name [ in word ] ; do list ; done The list of words following in is expanded, generating a list of items, and the set of expanded words is printed on the standard error, each preceded by a number. If the in word is omitted, the positional parameters are printed (see PARAMETERS below). select then displays the PS3 prompt and reads a line from the standard input. If the line consists of a number corresponding to one of the displayed words, then the value of name is set to that word. If the line is empty, the words and prompt are displayed again. If EOF is read, the select command completes and returns 1. Any other value read causes name to be set to null. The line read is saved in the variable REPLY. The list is executed after each selection until a break command is executed. The exit status of select is the exit status of the last command executed in list, or zero if no commands were executed. case word in [ [(] pattern [ | pattern ] ... ) list ;; ] ... esac A case command first expands word, and tries to match it against each pattern in turn, using the matching rules described under Pattern Matching below. The word is expanded using tilde expansion, parameter and variable expansion, arithmetic expansion, command substitution, process substitution and quote removal. Each pattern examined is expanded using tilde expansion, parameter and variable expansion, arithmetic expansion, command substitution, process substitution, and quote removal. If the nocasematch shell option is enabled, the match is performed without regard to the case of alphabetic characters. When a match is found, the corresponding list is executed. If the ;; operator is used, no subsequent matches are attempted after the first pattern match. Using ;& in place of ;; causes execution to continue with the list associated with the next set of patterns. Using ;;& in place of ;; causes the shell to test the next pattern list in the statement, if any, and execute any associated list on a successful match, continuing the case statement execution as if the pattern list had not matched. The exit status is zero if no pattern matches. Otherwise, it is the exit status of the last command executed in list. if list; then list; [ elif list; then list; ] ... [ else list; ] fi The if list is executed. If its exit status is zero, the then list is executed. Otherwise, each elif list is executed in turn, and if its exit status is zero, the corresponding then list is executed and the command completes. Otherwise, the else list is executed, if present. The exit status is the exit status of the last command executed, or zero if no condition tested true. while list-1; do list-2; done until list-1; do list-2; done The while command continuously executes the list list-2 as long as the last command in the list list-1 returns an exit status of zero. The until command is identical to the while command, except that the test is negated: list-2 is executed as long as the last command in list-1 returns a non-zero exit status. The exit status of the while and until commands is the exit status of the last command executed in list-2, or zero if none was executed. Coprocesses A coprocess is a shell command preceded by the coproc reserved word. A coprocess is executed asynchronously in a subshell, as if the command had been terminated with the & control operator, with a two-way pipe established between the executing shell and the coprocess. The syntax for a coprocess is: coproc [NAME] command [redirections] This creates a coprocess named NAME. command may be either a simple command or a compound command (see above). NAME is a shell variable name. If NAME is not supplied, the default name is COPROC. The recommended form to use for a coprocess is coproc NAME { command [redirections]; } This form is recommended because simple commands result in the coprocess always being named COPROC, and it is simpler to use and more complete than the other compound commands. If command is a compound command, NAME is optional. The word following coproc determines whether that word is interpreted as a variable name: it is interpreted as NAME if it is not a reserved word that introduces a compound command. If command is a simple command, NAME is not allowed; this is to avoid confusion between NAME and the first word of the simple command. When the coprocess is executed, the shell creates an array variable (see Arrays below) named NAME in the context of the executing shell. The standard output of command is connected via a pipe to a file descriptor in the executing shell, and that file descriptor is assigned to NAME[0]. The standard input of command is connected via a pipe to a file descriptor in the executing shell, and that file descriptor is assigned to NAME[1]. This pipe is established before any redirections specified by the command (see REDIRECTION below). The file descriptors can be utilized as arguments to shell commands and redirections using standard word expansions. Other than those created to execute command and process substitutions, the file descriptors are not available in subshells. The process ID of the shell spawned to execute the coprocess is available as the value of the variable NAME_PID. The wait builtin command may be used to wait for the coprocess to terminate. Since the coprocess is created as an asynchronous command, the coproc command always returns success. The return status of a coprocess is the exit status of command. Shell Function Definitions A shell function is an object that is called like a simple command and executes a compound command with a new set of positional parameters. Shell functions are declared as follows: fname () compound-command [redirection] function fname [()] compound-command [redirection] This defines a function named fname. The reserved word function is optional. If the function reserved word is supplied, the parentheses are optional. The body of the function is the compound command compound-command (see Compound Commands above). That command is usually a list of commands between { and }, but may be any command listed under Compound Commands above. If the function reserved word is used, but the parentheses are not supplied, the braces are recommended. compound-command is executed whenever fname is specified as the name of a simple command. When in posix mode, fname must be a valid shell name and may not be the name of one of the POSIX special builtins. In default mode, a function name can be any unquoted shell word that does not contain $. Any redirections (see REDIRECTION below) specified when a function is defined are performed when the function is executed. The exit status of a function definition is zero unless a syntax error occurs or a readonly function with the same name already exists. When executed, the exit status of a function is the exit status of the last command executed in the body. (See FUNCTIONS below.) COMMENTS top In a non-interactive shell, or an interactive shell in which the interactive_comments option to the shopt builtin is enabled (see SHELL BUILTIN COMMANDS below), a word beginning with # causes that word and all remaining characters on that line to be ignored. An interactive shell without the interactive_comments option enabled does not allow comments. The interactive_comments option is on by default in interactive shells. QUOTING top Quoting is used to remove the special meaning of certain characters or words to the shell. Quoting can be used to disable special treatment for special characters, to prevent reserved words from being recognized as such, and to prevent parameter expansion. Each of the metacharacters listed above under DEFINITIONS has special meaning to the shell and must be quoted if it is to represent itself. When the command history expansion facilities are being used (see HISTORY EXPANSION below), the history expansion character, usually !, must be quoted to prevent history expansion. There are three quoting mechanisms: the escape character, single quotes, and double quotes. A non-quoted backslash (\) is the escape character. It preserves the literal value of the next character that follows, with the exception of <newline>. If a \<newline> pair appears, and the backslash is not itself quoted, the \<newline> is treated as a line continuation (that is, it is removed from the input stream and effectively ignored). Enclosing characters in single quotes preserves the literal value of each character within the quotes. A single quote may not occur between single quotes, even when preceded by a backslash. Enclosing characters in double quotes preserves the literal value of all characters within the quotes, with the exception of $, `, \, and, when history expansion is enabled, !. When the shell is in posix mode, the ! has no special meaning within double quotes, even when history expansion is enabled. The characters $ and ` retain their special meaning within double quotes. The backslash retains its special meaning only when followed by one of the following characters: $, `, ", \, or <newline>. A double quote may be quoted within double quotes by preceding it with a backslash. If enabled, history expansion will be performed unless an ! appearing in double quotes is escaped using a backslash. The backslash preceding the ! is not removed. The special parameters * and @ have special meaning when in double quotes (see PARAMETERS below). Character sequences of the form $'string' are treated as a special variant of single quotes. The sequence expands to string, with backslash-escaped characters in string replaced as specified by the ANSI C standard. Backslash escape sequences, if present, are decoded as follows: \a alert (bell) \b backspace \e \E an escape character \f form feed \n new line \r carriage return \t horizontal tab \v vertical tab \\ backslash \' single quote \" double quote \? question mark \nnn the eight-bit character whose value is the octal value nnn (one to three octal digits) \xHH the eight-bit character whose value is the hexadecimal value HH (one or two hex digits) \uHHHH the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value HHHH (one to four hex digits) \UHHHHHHHH the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value HHHHHHHH (one to eight hex digits) \cx a control-x character The expanded result is single-quoted, as if the dollar sign had not been present. A double-quoted string preceded by a dollar sign ($"string") will cause the string to be translated according to the current locale. The gettext infrastructure performs the lookup and translation, using the LC_MESSAGES, TEXTDOMAINDIR, and TEXTDOMAIN shell variables. If the current locale is C or POSIX, if there are no translations available, or if the string is not translated, the dollar sign is ignored. This is a form of double quoting, so the string remains double-quoted by default, whether or not it is translated and replaced. If the noexpand_translation option is enabled using the shopt builtin, translated strings are single-quoted instead of double-quoted. See the description of shopt below under SHELLBUILTINCOMMANDS. PARAMETERS top A parameter is an entity that stores values. It can be a name, a number, or one of the special characters listed below under Special Parameters. A variable is a parameter denoted by a name. A variable has a value and zero or more attributes. Attributes are assigned using the declare builtin command (see declare below in SHELL BUILTIN COMMANDS). A parameter is set if it has been assigned a value. The null string is a valid value. Once a variable is set, it may be unset only by using the unset builtin command (see SHELL BUILTIN COMMANDS below). A variable may be assigned to by a statement of the form name=[value] If value is not given, the variable is assigned the null string. All values undergo tilde expansion, parameter and variable expansion, command substitution, arithmetic expansion, and quote removal (see EXPANSION below). If the variable has its integer attribute set, then value is evaluated as an arithmetic expression even if the $((...)) expansion is not used (see Arithmetic Expansion below). Word splitting and pathname expansion are not performed. Assignment statements may also appear as arguments to the alias, declare, typeset, export, readonly, and local builtin commands (declaration commands). When in posix mode, these builtins may appear in a command after one or more instances of the command builtin and retain these assignment statement properties. In the context where an assignment statement is assigning a value to a shell variable or array index, the += operator can be used to append to or add to the variable's previous value. This includes arguments to builtin commands such as declare that accept assignment statements (declaration commands). When += is applied to a variable for which the integer attribute has been set, value is evaluated as an arithmetic expression and added to the variable's current value, which is also evaluated. When += is applied to an array variable using compound assignment (see Arrays below), the variable's value is not unset (as it is when using =), and new values are appended to the array beginning at one greater than the array's maximum index (for indexed arrays) or added as additional key-value pairs in an associative array. When applied to a string-valued variable, value is expanded and appended to the variable's value. A variable can be assigned the nameref attribute using the -n option to the declare or local builtin commands (see the descriptions of declare and local below) to create a nameref, or a reference to another variable. This allows variables to be manipulated indirectly. Whenever the nameref variable is referenced, assigned to, unset, or has its attributes modified (other than using or changing the nameref attribute itself), the operation is actually performed on the variable specified by the nameref variable's value. A nameref is commonly used within shell functions to refer to a variable whose name is passed as an argument to the function. For instance, if a variable name is passed to a shell function as its first argument, running declare -n ref=$1 inside the function creates a nameref variable ref whose value is the variable name passed as the first argument. References and assignments to ref, and changes to its attributes, are treated as references, assignments, and attribute modifications to the variable whose name was passed as $1. If the control variable in a for loop has the nameref attribute, the list of words can be a list of shell variables, and a name reference will be established for each word in the list, in turn, when the loop is executed. Array variables cannot be given the nameref attribute. However, nameref variables can reference array variables and subscripted array variables. Namerefs can be unset using the -n option to the unset builtin. Otherwise, if unset is executed with the name of a nameref variable as an argument, the variable referenced by the nameref variable will be unset. Positional Parameters A positional parameter is a parameter denoted by one or more digits, other than the single digit 0. Positional parameters are assigned from the shell's arguments when it is invoked, and may be reassigned using the set builtin command. Positional parameters may not be assigned to with assignment statements. The positional parameters are temporarily replaced when a shell function is executed (see FUNCTIONS below). When a positional parameter consisting of more than a single digit is expanded, it must be enclosed in braces (see EXPANSION below). Special Parameters The shell treats several parameters specially. These parameters may only be referenced; assignment to them is not allowed. * Expands to the positional parameters, starting from one. When the expansion is not within double quotes, each positional parameter expands to a separate word. In contexts where it is performed, those words are subject to further word splitting and pathname expansion. When the expansion occurs within double quotes, it expands to a single word with the value of each parameter separated by the first character of the IFS special variable. That is, "$*" is equivalent to "$1c$2c...", where c is the first character of the value of the IFS variable. If IFS is unset, the parameters are separated by spaces. If IFS is null, the parameters are joined without intervening separators. @ Expands to the positional parameters, starting from one. In contexts where word splitting is performed, this expands each positional parameter to a separate word; if not within double quotes, these words are subject to word splitting. In contexts where word splitting is not performed, this expands to a single word with each positional parameter separated by a space. When the expansion occurs within double quotes, each parameter expands to a separate word. That is, "$@" is equivalent to "$1" "$2" ... If the double-quoted expansion occurs within a word, the expansion of the first parameter is joined with the beginning part of the original word, and the expansion of the last parameter is joined with the last part of the original word. When there are no positional parameters, "$@" and $@ expand to nothing (i.e., they are removed). # Expands to the number of positional parameters in decimal. ? Expands to the exit status of the most recently executed foreground pipeline. - Expands to the current option flags as specified upon invocation, by the set builtin command, or those set by the shell itself (such as the -i option). $ Expands to the process ID of the shell. In a subshell, it expands to the process ID of the current shell, not the subshell. ! Expands to the process ID of the job most recently placed into the background, whether executed as an asynchronous command or using the bg builtin (see JOB CONTROL below). 0 Expands to the name of the shell or shell script. This is set at shell initialization. If bash is invoked with a file of commands, $0 is set to the name of that file. If bash is started with the -c option, then $0 is set to the first argument after the string to be executed, if one is present. Otherwise, it is set to the filename used to invoke bash, as given by argument zero. Shell Variables The following variables are set by the shell: _ At shell startup, set to the pathname used to invoke the shell or shell script being executed as passed in the environment or argument list. Subsequently, expands to the last argument to the previous simple command executed in the foreground, after expansion. Also set to the full pathname used to invoke each command executed and placed in the environment exported to that command. When checking mail, this parameter holds the name of the mail file currently being checked. BASH Expands to the full filename used to invoke this instance of bash. BASHOPTS A colon-separated list of enabled shell options. Each word in the list is a valid argument for the -s option to the shopt builtin command (see SHELL BUILTIN COMMANDS below). The options appearing in BASHOPTS are those reported as on by shopt. If this variable is in the environment when bash starts up, each shell option in the list will be enabled before reading any startup files. This variable is read-only. BASHPID Expands to the process ID of the current bash process. This differs from $$ under certain circumstances, such as subshells that do not require bash to be re-initialized. Assignments to BASHPID have no effect. If BASHPID is unset, it loses its special properties, even if it is subsequently reset. BASH_ALIASES An associative array variable whose members correspond to the internal list of aliases as maintained by the alias builtin. Elements added to this array appear in the alias list; however, unsetting array elements currently does not cause aliases to be removed from the alias list. If BASH_ALIASES is unset, it loses its special properties, even if it is subsequently reset. BASH_ARGC An array variable whose values are the number of parameters in each frame of the current bash execution call stack. The number of parameters to the current subroutine (shell function or script executed with . or source) is at the top of the stack. When a subroutine is executed, the number of parameters passed is pushed onto BASH_ARGC. The shell sets BASH_ARGC only when in extended debugging mode (see the description of the extdebug option to the shopt builtin below). Setting extdebug after the shell has started to execute a script, or referencing this variable when extdebug is not set, may result in inconsistent values. BASH_ARGV An array variable containing all of the parameters in the current bash execution call stack. The final parameter of the last subroutine call is at the top of the stack; the first parameter of the initial call is at the bottom. When a subroutine is executed, the parameters supplied are pushed onto BASH_ARGV. The shell sets BASH_ARGV only when in extended debugging mode (see the description of the extdebug option to the shopt builtin below). Setting extdebug after the shell has started to execute a script, or referencing this variable when extdebug is not set, may result in inconsistent values. BASH_ARGV0 When referenced, this variable expands to the name of the shell or shell script (identical to $0; see the description of special parameter 0 above). Assignment to BASH_ARGV0 causes the value assigned to also be assigned to $0. If BASH_ARGV0 is unset, it loses its special properties, even if it is subsequently reset. BASH_CMDS An associative array variable whose members correspond to the internal hash table of commands as maintained by the hash builtin. Elements added to this array appear in the hash table; however, unsetting array elements currently does not cause command names to be removed from the hash table. If BASH_CMDS is unset, it loses its special properties, even if it is subsequently reset. BASH_COMMAND The command currently being executed or about to be executed, unless the shell is executing a command as the result of a trap, in which case it is the command executing at the time of the trap. If BASH_COMMAND is unset, it loses its special properties, even if it is subsequently reset. BASH_EXECUTION_STRING The command argument to the -c invocation option. BASH_LINENO An array variable whose members are the line numbers in source files where each corresponding member of FUNCNAME was invoked. ${BASH_LINENO[$i]} is the line number in the source file (${BASH_SOURCE[$i+1]}) where ${FUNCNAME[$i]} was called (or ${BASH_LINENO[$i-1]} if referenced within another shell function). Use LINENO to obtain the current line number. BASH_LOADABLES_PATH A colon-separated list of directories in which the shell looks for dynamically loadable builtins specified by the enable command. BASH_REMATCH An array variable whose members are assigned by the =~ binary operator to the [[ conditional command. The element with index 0 is the portion of the string matching the entire regular expression. The element with index n is the portion of the string matching the nth parenthesized subexpression. BASH_SOURCE An array variable whose members are the source filenames where the corresponding shell function names in the FUNCNAME array variable are defined. The shell function ${FUNCNAME[$i]} is defined in the file ${BASH_SOURCE[$i]} and called from ${BASH_SOURCE[$i+1]}. BASH_SUBSHELL Incremented by one within each subshell or subshell environment when the shell begins executing in that environment. The initial value is 0. If BASH_SUBSHELL is unset, it loses its special properties, even if it is subsequently reset. BASH_VERSINFO A readonly array variable whose members hold version information for this instance of bash. The values assigned to the array members are as follows: BASH_VERSINFO[0] The major version number (the release). BASH_VERSINFO[1] The minor version number (the version). BASH_VERSINFO[2] The patch level. BASH_VERSINFO[3] The build version. BASH_VERSINFO[4] The release status (e.g., beta1). BASH_VERSINFO[5] The value of MACHTYPE. BASH_VERSION Expands to a string describing the version of this instance of bash. COMP_CWORD An index into ${COMP_WORDS} of the word containing the current cursor position. This variable is available only in shell functions invoked by the programmable completion facilities (see Programmable Completion below). COMP_KEY The key (or final key of a key sequence) used to invoke the current completion function. COMP_LINE The current command line. This variable is available only in shell functions and external commands invoked by the programmable completion facilities (see Programmable Completion below). COMP_POINT The index of the current cursor position relative to the beginning of the current command. If the current cursor position is at the end of the current command, the value of this variable is equal to ${#COMP_LINE}. This variable is available only in shell functions and external commands invoked by the programmable completion facilities (see Programmable Completion below). COMP_TYPE Set to an integer value corresponding to the type of completion attempted that caused a completion function to be called: TAB, for normal completion, ?, for listing completions after successive tabs, !, for listing alternatives on partial word completion, @, to list completions if the word is not unmodified, or %, for menu completion. This variable is available only in shell functions and external commands invoked by the programmable completion facilities (see Programmable Completion below). COMP_WORDBREAKS The set of characters that the readline library treats as word separators when performing word completion. If COMP_WORDBREAKS is unset, it loses its special properties, even if it is subsequently reset. COMP_WORDS An array variable (see Arrays below) consisting of the individual words in the current command line. The line is split into words as readline would split it, using COMP_WORDBREAKS as described above. This variable is available only in shell functions invoked by the programmable completion facilities (see Programmable Completion below). COPROC An array variable (see Arrays below) created to hold the file descriptors for output from and input to an unnamed coprocess (see Coprocesses above). DIRSTACK An array variable (see Arrays below) containing the current contents of the directory stack. Directories appear in the stack in the order they are displayed by the dirs builtin. Assigning to members of this array variable may be used to modify directories already in the stack, but the pushd and popd builtins must be used to add and remove directories. Assignment to this variable will not change the current directory. If DIRSTACK is unset, it loses its special properties, even if it is subsequently reset. EPOCHREALTIME Each time this parameter is referenced, it expands to the number of seconds since the Unix Epoch (see time(3)) as a floating point value with micro-second granularity. Assignments to EPOCHREALTIME are ignored. If EPOCHREALTIME is unset, it loses its special properties, even if it is subsequently reset. EPOCHSECONDS Each time this parameter is referenced, it expands to the number of seconds since the Unix Epoch (see time(3)). Assignments to EPOCHSECONDS are ignored. If EPOCHSECONDS is unset, it loses its special properties, even if it is subsequently reset. EUID Expands to the effective user ID of the current user, initialized at shell startup. This variable is readonly. FUNCNAME An array variable containing the names of all shell functions currently in the execution call stack. The element with index 0 is the name of any currently- executing shell function. The bottom-most element (the one with the highest index) is "main". This variable exists only when a shell function is executing. Assignments to FUNCNAME have no effect. If FUNCNAME is unset, it loses its special properties, even if it is subsequently reset. This variable can be used with BASH_LINENO and BASH_SOURCE. Each element of FUNCNAME has corresponding elements in BASH_LINENO and BASH_SOURCE to describe the call stack. For instance, ${FUNCNAME[$i]} was called from the file ${BASH_SOURCE[$i+1]} at line number ${BASH_LINENO[$i]}. The caller builtin displays the current call stack using this information. GROUPS An array variable containing the list of groups of which the current user is a member. Assignments to GROUPS have no effect. If GROUPS is unset, it loses its special properties, even if it is subsequently reset. HISTCMD The history number, or index in the history list, of the current command. Assignments to HISTCMD are ignored. If HISTCMD is unset, it loses its special properties, even if it is subsequently reset. HOSTNAME Automatically set to the name of the current host. HOSTTYPE Automatically set to a string that uniquely describes the type of machine on which bash is executing. The default is system-dependent. LINENO Each time this parameter is referenced, the shell substitutes a decimal number representing the current sequential line number (starting with 1) within a script or function. When not in a script or function, the value substituted is not guaranteed to be meaningful. If LINENO is unset, it loses its special properties, even if it is subsequently reset. MACHTYPE Automatically set to a string that fully describes the system type on which bash is executing, in the standard GNU cpu-company-system format. The default is system- dependent. MAPFILE An array variable (see Arrays below) created to hold the text read by the mapfile builtin when no variable name is supplied. OLDPWD The previous working directory as set by the cd command. OPTARG The value of the last option argument processed by the getopts builtin command (see SHELL BUILTIN COMMANDS below). OPTIND The index of the next argument to be processed by the getopts builtin command (see SHELL BUILTIN COMMANDS below). OSTYPE Automatically set to a string that describes the operating system on which bash is executing. The default is system- dependent. PIPESTATUS An array variable (see Arrays below) containing a list of exit status values from the processes in the most- recently-executed foreground pipeline (which may contain only a single command). PPID The process ID of the shell's parent. This variable is readonly. PWD The current working directory as set by the cd command. RANDOM Each time this parameter is referenced, it expands to a random integer between 0 and 32767. Assigning a value to RANDOM initializes (seeds) the sequence of random numbers. If RANDOM is unset, it loses its special properties, even if it is subsequently reset. READLINE_ARGUMENT Any numeric argument given to a readline command that was defined using "bind -x" (see SHELL BUILTIN COMMANDS below) when it was invoked. READLINE_LINE The contents of the readline line buffer, for use with "bind -x" (see SHELL BUILTIN COMMANDS below). READLINE_MARK The position of the mark (saved insertion point) in the readline line buffer, for use with "bind -x" (see SHELL BUILTIN COMMANDS below). The characters between the insertion point and the mark are often called the region. READLINE_POINT The position of the insertion point in the readline line buffer, for use with "bind -x" (see SHELL BUILTIN COMMANDS below). REPLY Set to the line of input read by the read builtin command when no arguments are supplied. SECONDS Each time this parameter is referenced, it expands to the number of seconds since shell invocation. If a value is assigned to SECONDS, the value returned upon subsequent references is the number of seconds since the assignment plus the value assigned. The number of seconds at shell invocation and the current time are always determined by querying the system clock. If SECONDS is unset, it loses its special properties, even if it is subsequently reset. SHELLOPTS A colon-separated list of enabled shell options. Each word in the list is a valid argument for the -o option to the set builtin command (see SHELL BUILTIN COMMANDS below). The options appearing in SHELLOPTS are those reported as on by set -o. If this variable is in the environment when bash starts up, each shell option in the list will be enabled before reading any startup files. This variable is read-only. SHLVL Incremented by one each time an instance of bash is started. SRANDOM This variable expands to a 32-bit pseudo-random number each time it is referenced. The random number generator is not linear on systems that support /dev/urandom or arc4random, so each returned number has no relationship to the numbers preceding it. The random number generator cannot be seeded, so assignments to this variable have no effect. If SRANDOM is unset, it loses its special properties, even if it is subsequently reset. UID Expands to the user ID of the current user, initialized at shell startup. This variable is readonly. The following variables are used by the shell. In some cases, bash assigns a default value to a variable; these cases are noted below. BASH_COMPAT The value is used to set the shell's compatibility level. See SHELL COMPATIBILITY MODE below for a description of the various compatibility levels and their effects. The value may be a decimal number (e.g., 4.2) or an integer (e.g., 42) corresponding to the desired compatibility level. If BASH_COMPAT is unset or set to the empty string, the compatibility level is set to the default for the current version. If BASH_COMPAT is set to a value that is not one of the valid compatibility levels, the shell prints an error message and sets the compatibility level to the default for the current version. The valid values correspond to the compatibility levels described below under SHELL COMPATIBILITY MODE. For example, 4.2 and 42 are valid values that correspond to the compat42 shopt option and set the compatibility level to 42. The current version is also a valid value. BASH_ENV If this parameter is set when bash is executing a shell script, its value is interpreted as a filename containing commands to initialize the shell, as in ~/.bashrc. The value of BASH_ENV is subjected to parameter expansion, command substitution, and arithmetic expansion before being interpreted as a filename. PATH is not used to search for the resultant filename. BASH_XTRACEFD If set to an integer corresponding to a valid file descriptor, bash will write the trace output generated when set -x is enabled to that file descriptor. The file descriptor is closed when BASH_XTRACEFD is unset or assigned a new value. Unsetting BASH_XTRACEFD or assigning it the empty string causes the trace output to be sent to the standard error. Note that setting BASH_XTRACEFD to 2 (the standard error file descriptor) and then unsetting it will result in the standard error being closed. CDPATH The search path for the cd command. This is a colon- separated list of directories in which the shell looks for destination directories specified by the cd command. A sample value is ".:~:/usr". CHILD_MAX Set the number of exited child status values for the shell to remember. Bash will not allow this value to be decreased below a POSIX-mandated minimum, and there is a maximum value (currently 8192) that this may not exceed. The minimum value is system-dependent. COLUMNS Used by the select compound command to determine the terminal width when printing selection lists. Automatically set if the checkwinsize option is enabled or in an interactive shell upon receipt of a SIGWINCH. COMPREPLY An array variable from which bash reads the possible completions generated by a shell function invoked by the programmable completion facility (see Programmable Completion below). Each array element contains one possible completion. EMACS If bash finds this variable in the environment when the shell starts with value "t", it assumes that the shell is running in an Emacs shell buffer and disables line editing. ENV Expanded and executed similarly to BASH_ENV (see INVOCATION above) when an interactive shell is invoked in posix mode. EXECIGNORE A colon-separated list of shell patterns (see Pattern Matching) defining the list of filenames to be ignored by command search using PATH. Files whose full pathnames match one of these patterns are not considered executable files for the purposes of completion and command execution via PATH lookup. This does not affect the behavior of the [, test, and [[ commands. Full pathnames in the command hash table are not subject to EXECIGNORE. Use this variable to ignore shared library files that have the executable bit set, but are not executable files. The pattern matching honors the setting of the extglob shell option. FCEDIT The default editor for the fc builtin command. FIGNORE A colon-separated list of suffixes to ignore when performing filename completion (see READLINE below). A filename whose suffix matches one of the entries in FIGNORE is excluded from the list of matched filenames. A sample value is ".o:~". FUNCNEST If set to a numeric value greater than 0, defines a maximum function nesting level. Function invocations that exceed this nesting level will cause the current command to abort. GLOBIGNORE A colon-separated list of patterns defining the set of file names to be ignored by pathname expansion. If a file name matched by a pathname expansion pattern also matches one of the patterns in GLOBIGNORE, it is removed from the list of matches. HISTCONTROL A colon-separated list of values controlling how commands are saved on the history list. If the list of values includes ignorespace, lines which begin with a space character are not saved in the history list. A value of ignoredups causes lines matching the previous history entry to not be saved. A value of ignoreboth is shorthand for ignorespace and ignoredups. A value of erasedups causes all previous lines matching the current line to be removed from the history list before that line is saved. Any value not in the above list is ignored. If HISTCONTROL is unset, or does not include a valid value, all lines read by the shell parser are saved on the history list, subject to the value of HISTIGNORE. The second and subsequent lines of a multi-line compound command are not tested, and are added to the history regardless of the value of HISTCONTROL. HISTFILE The name of the file in which command history is saved (see HISTORY below). The default value is ~/.bash_history. If unset, the command history is not saved when a shell exits. HISTFILESIZE The maximum number of lines contained in the history file. When this variable is assigned a value, the history file is truncated, if necessary, to contain no more than that number of lines by removing the oldest entries. The history file is also truncated to this size after writing it when a shell exits. If the value is 0, the history file is truncated to zero size. Non-numeric values and numeric values less than zero inhibit truncation. The shell sets the default value to the value of HISTSIZE after reading any startup files. HISTIGNORE A colon-separated list of patterns used to decide which command lines should be saved on the history list. Each pattern is anchored at the beginning of the line and must match the complete line (no implicit `*' is appended). Each pattern is tested against the line after the checks specified by HISTCONTROL are applied. In addition to the normal shell pattern matching characters, `&' matches the previous history line. `&' may be escaped using a backslash; the backslash is removed before attempting a match. The second and subsequent lines of a multi-line compound command are not tested, and are added to the history regardless of the value of HISTIGNORE. The pattern matching honors the setting of the extglob shell option. HISTSIZE The number of commands to remember in the command history (see HISTORY below). If the value is 0, commands are not saved in the history list. Numeric values less than zero result in every command being saved on the history list (there is no limit). The shell sets the default value to 500 after reading any startup files. HISTTIMEFORMAT If this variable is set and not null, its value is used as a format string for strftime(3) to print the time stamp associated with each history entry displayed by the history builtin. If this variable is set, time stamps are written to the history file so they may be preserved across shell sessions. This uses the history comment character to distinguish timestamps from other history lines. HOME The home directory of the current user; the default argument for the cd builtin command. The value of this variable is also used when performing tilde expansion. HOSTFILE Contains the name of a file in the same format as /etc/hosts that should be read when the shell needs to complete a hostname. The list of possible hostname completions may be changed while the shell is running; the next time hostname completion is attempted after the value is changed, bash adds the contents of the new file to the existing list. If HOSTFILE is set, but has no value, or does not name a readable file, bash attempts to read /etc/hosts to obtain the list of possible hostname completions. When HOSTFILE is unset, the hostname list is cleared. IFS The Internal Field Separator that is used for word splitting after expansion and to split lines into words with the read builtin command. The default value is ``<space><tab><newline>''. IGNOREEOF Controls the action of an interactive shell on receipt of an EOF character as the sole input. If set, the value is the number of consecutive EOF characters which must be typed as the first characters on an input line before bash exits. If the variable exists but does not have a numeric value, or has no value, the default value is 10. If it does not exist, EOF signifies the end of input to the shell. INPUTRC The filename for the readline startup file, overriding the default of ~/.inputrc (see READLINE below). INSIDE_EMACS If this variable appears in the environment when the shell starts, bash assumes that it is running inside an Emacs shell buffer and may disable line editing, depending on the value of TERM. LANG Used to determine the locale category for any category not specifically selected with a variable starting with LC_. LC_ALL This variable overrides the value of LANG and any other LC_ variable specifying a locale category. LC_COLLATE This variable determines the collation order used when sorting the results of pathname expansion, and determines the behavior of range expressions, equivalence classes, and collating sequences within pathname expansion and pattern matching. LC_CTYPE This variable determines the interpretation of characters and the behavior of character classes within pathname expansion and pattern matching. LC_MESSAGES This variable determines the locale used to translate double-quoted strings preceded by a $. LC_NUMERIC This variable determines the locale category used for number formatting. LC_TIME This variable determines the locale category used for data and time formatting. LINES Used by the select compound command to determine the column length for printing selection lists. Automatically set if the checkwinsize option is enabled or in an interactive shell upon receipt of a SIGWINCH. MAIL If this parameter is set to a file or directory name and the MAILPATH variable is not set, bash informs the user of the arrival of mail in the specified file or Maildir- format directory. MAILCHECK Specifies how often (in seconds) bash checks for mail. The default is 60 seconds. When it is time to check for mail, the shell does so before displaying the primary prompt. If this variable is unset, or set to a value that is not a number greater than or equal to zero, the shell disables mail checking. MAILPATH A colon-separated list of filenames to be checked for mail. The message to be printed when mail arrives in a particular file may be specified by separating the filename from the message with a `?'. When used in the text of the message, $_ expands to the name of the current mailfile. Example: MAILPATH='/var/mail/bfox?"You have mail":~/shell-mail?"$_ has mail!"' Bash can be configured to supply a default value for this variable (there is no value by default), but the location of the user mail files that it uses is system dependent (e.g., /var/mail/$USER). OPTERR If set to the value 1, bash displays error messages generated by the getopts builtin command (see SHELL BUILTIN COMMANDS below). OPTERR is initialized to 1 each time the shell is invoked or a shell script is executed. PATH The search path for commands. It is a colon-separated list of directories in which the shell looks for commands (see COMMAND EXECUTION below). A zero-length (null) directory name in the value of PATH indicates the current directory. A null directory name may appear as two adjacent colons, or as an initial or trailing colon. The default path is system-dependent, and is set by the administrator who installs bash. A common value is ``/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin''. POSIXLY_CORRECT If this variable is in the environment when bash starts, the shell enters posix mode before reading the startup files, as if the --posix invocation option had been supplied. If it is set while the shell is running, bash enables posix mode, as if the command set -o posix had been executed. When the shell enters posix mode, it sets this variable if it was not already set. PROMPT_COMMAND If this variable is set, and is an array, the value of each set element is executed as a command prior to issuing each primary prompt. If this is set but not an array variable, its value is used as a command to execute instead. PROMPT_DIRTRIM If set to a number greater than zero, the value is used as the number of trailing directory components to retain when expanding the \w and \W prompt string escapes (see PROMPTING below). Characters removed are replaced with an ellipsis. PS0 The value of this parameter is expanded (see PROMPTING below) and displayed by interactive shells after reading a command and before the command is executed. PS1 The value of this parameter is expanded (see PROMPTING below) and used as the primary prompt string. The default value is ``\s-\v\$ ''. PS2 The value of this parameter is expanded as with PS1 and used as the secondary prompt string. The default is ``> ''. PS3 The value of this parameter is used as the prompt for the select command (see SHELL GRAMMAR above). PS4 The value of this parameter is expanded as with PS1 and the value is printed before each command bash displays during an execution trace. The first character of the expanded value of PS4 is replicated multiple times, as necessary, to indicate multiple levels of indirection. The default is ``+ ''. SHELL This variable expands to the full pathname to the shell. If it is not set when the shell starts, bash assigns to it the full pathname of the current user's login shell. TIMEFORMAT The value of this parameter is used as a format string specifying how the timing information for pipelines prefixed with the time reserved word should be displayed. The % character introduces an escape sequence that is expanded to a time value or other information. The escape sequences and their meanings are as follows; the braces denote optional portions. %% A literal %. %[p][l]R The elapsed time in seconds. %[p][l]U The number of CPU seconds spent in user mode. %[p][l]S The number of CPU seconds spent in system mode. %P The CPU percentage, computed as (%U + %S) / %R. The optional p is a digit specifying the precision, the number of fractional digits after a decimal point. A value of 0 causes no decimal point or fraction to be output. At most three places after the decimal point may be specified; values of p greater than 3 are changed to 3. If p is not specified, the value 3 is used. The optional l specifies a longer format, including minutes, of the form MMmSS.FFs. The value of p determines whether or not the fraction is included. If this variable is not set, bash acts as if it had the value $'\nreal\t%3lR\nuser\t%3lU\nsys\t%3lS'. If the value is null, no timing information is displayed. A trailing newline is added when the format string is displayed. TMOUT If set to a value greater than zero, TMOUT is treated as the default timeout for the read builtin. The select command terminates if input does not arrive after TMOUT seconds when input is coming from a terminal. In an interactive shell, the value is interpreted as the number of seconds to wait for a line of input after issuing the primary prompt. Bash terminates after waiting for that number of seconds if a complete line of input does not arrive. TMPDIR If set, bash uses its value as the name of a directory in which bash creates temporary files for the shell's use. auto_resume This variable controls how the shell interacts with the user and job control. If this variable is set, single word simple commands without redirections are treated as candidates for resumption of an existing stopped job. There is no ambiguity allowed; if there is more than one job beginning with the string typed, the job most recently accessed is selected. The name of a stopped job, in this context, is the command line used to start it. If set to the value exact, the string supplied must match the name of a stopped job exactly; if set to substring, the string supplied needs to match a substring of the name of a stopped job. The substring value provides functionality analogous to the %? job identifier (see JOB CONTROL below). If set to any other value, the supplied string must be a prefix of a stopped job's name; this provides functionality analogous to the %string job identifier. histchars The two or three characters which control history expansion and tokenization (see HISTORY EXPANSION below). The first character is the history expansion character, the character which signals the start of a history expansion, normally `!'. The second character is the quick substitution character, which is used as shorthand for re-running the previous command entered, substituting one string for another in the command. The default is `^'. The optional third character is the character which indicates that the remainder of the line is a comment when found as the first character of a word, normally `#'. The history comment character causes history substitution to be skipped for the remaining words on the line. It does not necessarily cause the shell parser to treat the rest of the line as a comment. Arrays Bash provides one-dimensional indexed and associative array variables. Any variable may be used as an indexed array; the declare builtin will explicitly declare an array. There is no maximum limit on the size of an array, nor any requirement that members be indexed or assigned contiguously. Indexed arrays are referenced using integers (including arithmetic expressions) and are zero-based; associative arrays are referenced using arbitrary strings. Unless otherwise noted, indexed array indices must be non-negative integers. An indexed array is created automatically if any variable is assigned to using the syntax name[subscript]=value. The subscript is treated as an arithmetic expression that must evaluate to a number. To explicitly declare an indexed array, use declare -a name (see SHELL BUILTIN COMMANDS below). declare -a name[subscript] is also accepted; the subscript is ignored. Associative arrays are created using declare -A name. Attributes may be specified for an array variable using the declare and readonly builtins. Each attribute applies to all members of an array. Arrays are assigned to using compound assignments of the form name=(value1 ... valuen), where each value may be of the form [subscript]=string. Indexed array assignments do not require anything but string. Each value in the list is expanded using all the shell expansions described below under EXPANSION. When assigning to indexed arrays, if the optional brackets and subscript are supplied, that index is assigned to; otherwise the index of the element assigned is the last index assigned to by the statement plus one. Indexing starts at zero. When assigning to an associative array, the words in a compound assignment may be either assignment statements, for which the subscript is required, or a list of words that is interpreted as a sequence of alternating keys and values: name=( key1 value1 key2 value2 ...). These are treated identically to name=( [key1]=value1 [key2]=value2 ...). The first word in the list determines how the remaining words are interpreted; all assignments in a list must be of the same type. When using key/value pairs, the keys may not be missing or empty; a final missing value is treated like the empty string. This syntax is also accepted by the declare builtin. Individual array elements may be assigned to using the name[subscript]=value syntax introduced above. When assigning to an indexed array, if name is subscripted by a negative number, that number is interpreted as relative to one greater than the maximum index of name, so negative indices count back from the end of the array, and an index of -1 references the last element. The += operator will append to an array variable when assigning using the compound assignment syntax; see PARAMETERS above. Any element of an array may be referenced using ${name[subscript]}. The braces are required to avoid conflicts with pathname expansion. If subscript is @ or *, the word expands to all members of name. These subscripts differ only when the word appears within double quotes. If the word is double-quoted, ${name[*]} expands to a single word with the value of each array member separated by the first character of the IFS special variable, and ${name[@]} expands each element of name to a separate word. When there are no array members, ${name[@]} expands to nothing. If the double-quoted expansion occurs within a word, the expansion of the first parameter is joined with the beginning part of the original word, and the expansion of the last parameter is joined with the last part of the original word. This is analogous to the expansion of the special parameters * and @ (see Special Parameters above). ${#name[subscript]} expands to the length of ${name[subscript]}. If subscript is * or @, the expansion is the number of elements in the array. If the subscript used to reference an element of an indexed array evaluates to a number less than zero, it is interpreted as relative to one greater than the maximum index of the array, so negative indices count back from the end of the array, and an index of -1 references the last element. Referencing an array variable without a subscript is equivalent to referencing the array with a subscript of 0. Any reference to a variable using a valid subscript is legal, and bash will create an array if necessary. An array variable is considered set if a subscript has been assigned a value. The null string is a valid value. It is possible to obtain the keys (indices) of an array as well as the values. ${!name[@]} and ${!name[*]} expand to the indices assigned in array variable name. The treatment when in double quotes is similar to the expansion of the special parameters @ and * within double quotes. The unset builtin is used to destroy arrays. unset name[subscript] destroys the array element at index subscript, for both indexed and associative arrays. Negative subscripts to indexed arrays are interpreted as described above. Unsetting the last element of an array variable does not unset the variable. unset name, where name is an array, removes the entire array. unset name[subscript], where subscript is * or @, behaves differently depending on whether name is an indexed or associative array. If name is an associative array, this unsets the element with subscript * or @. If name is an indexed array, unset removes all of the elements but does not remove the array itself. When using a variable name with a subscript as an argument to a command, such as with unset, without using the word expansion syntax described above, the argument is subject to pathname expansion. If pathname expansion is not desired, the argument should be quoted. The declare, local, and readonly builtins each accept a -a option to specify an indexed array and a -A option to specify an associative array. If both options are supplied, -A takes precedence. The read builtin accepts a -a option to assign a list of words read from the standard input to an array. The set and declare builtins display array values in a way that allows them to be reused as assignments. EXPANSION top Expansion is performed on the command line after it has been split into words. There are seven kinds of expansion performed: brace expansion, tilde expansion, parameter and variable expansion, command substitution, arithmetic expansion, word splitting, and pathname expansion. The order of expansions is: brace expansion; tilde expansion, parameter and variable expansion, arithmetic expansion, and command substitution (done in a left-to-right fashion); word splitting; and pathname expansion. On systems that can support it, there is an additional expansion available: process substitution. This is performed at the same time as tilde, parameter, variable, and arithmetic expansion and command substitution. After these expansions are performed, quote characters present in the original word are removed unless they have been quoted themselves (quote removal). Only brace expansion, word splitting, and pathname expansion can increase the number of words of the expansion; other expansions expand a single word to a single word. The only exceptions to this are the expansions of "$@" and "${name[@]}", and, in most cases, $* and ${name[*]} as explained above (see PARAMETERS). Brace Expansion Brace expansion is a mechanism by which arbitrary strings may be generated. This mechanism is similar to pathname expansion, but the filenames generated need not exist. Patterns to be brace expanded take the form of an optional preamble, followed by either a series of comma-separated strings or a sequence expression between a pair of braces, followed by an optional postscript. The preamble is prefixed to each string contained within the braces, and the postscript is then appended to each resulting string, expanding left to right. Brace expansions may be nested. The results of each expanded string are not sorted; left to right order is preserved. For example, a{d,c,b}e expands into `ade ace abe'. A sequence expression takes the form {x..y[..incr]}, where x and y are either integers or single letters, and incr, an optional increment, is an integer. When integers are supplied, the expression expands to each number between x and y, inclusive. Supplied integers may be prefixed with 0 to force each term to have the same width. When either x or y begins with a zero, the shell attempts to force all generated terms to contain the same number of digits, zero-padding where necessary. When letters are supplied, the expression expands to each character lexicographically between x and y, inclusive, using the default C locale. Note that both x and y must be of the same type (integer or letter). When the increment is supplied, it is used as the difference between each term. The default increment is 1 or -1 as appropriate. Brace expansion is performed before any other expansions, and any characters special to other expansions are preserved in the result. It is strictly textual. Bash does not apply any syntactic interpretation to the context of the expansion or the text between the braces. A correctly-formed brace expansion must contain unquoted opening and closing braces, and at least one unquoted comma or a valid sequence expression. Any incorrectly formed brace expansion is left unchanged. A { or , may be quoted with a backslash to prevent its being considered part of a brace expression. To avoid conflicts with parameter expansion, the string ${ is not considered eligible for brace expansion, and inhibits brace expansion until the closing }. This construct is typically used as shorthand when the common prefix of the strings to be generated is longer than in the above example: mkdir /usr/local/src/bash/{old,new,dist,bugs} or chown root /usr/{ucb/{ex,edit},lib/{ex?.?*,how_ex}} Brace expansion introduces a slight incompatibility with historical versions of sh. sh does not treat opening or closing braces specially when they appear as part of a word, and preserves them in the output. Bash removes braces from words as a consequence of brace expansion. For example, a word entered to sh as file{1,2} appears identically in the output. The same word is output as file1 file2 after expansion by bash. If strict compatibility with sh is desired, start bash with the +B option or disable brace expansion with the +B option to the set command (see SHELL BUILTIN COMMANDS below). Tilde Expansion If a word begins with an unquoted tilde character (`~'), all of the characters preceding the first unquoted slash (or all characters, if there is no unquoted slash) are considered a tilde-prefix. If none of the characters in the tilde-prefix are quoted, the characters in the tilde-prefix following the tilde are treated as a possible login name. If this login name is the null string, the tilde is replaced with the value of the shell parameter HOME. If HOME is unset, the home directory of the user executing the shell is substituted instead. Otherwise, the tilde-prefix is replaced with the home directory associated with the specified login name. If the tilde-prefix is a `~+', the value of the shell variable PWD replaces the tilde-prefix. If the tilde-prefix is a `~-', the value of the shell variable OLDPWD, if it is set, is substituted. If the characters following the tilde in the tilde- prefix consist of a number N, optionally prefixed by a `+' or a `-', the tilde-prefix is replaced with the corresponding element from the directory stack, as it would be displayed by the dirs builtin invoked with the tilde-prefix as an argument. If the characters following the tilde in the tilde-prefix consist of a number without a leading `+' or `-', `+' is assumed. If the login name is invalid, or the tilde expansion fails, the word is unchanged. Each variable assignment is checked for unquoted tilde-prefixes immediately following a : or the first =. In these cases, tilde expansion is also performed. Consequently, one may use filenames with tildes in assignments to PATH, MAILPATH, and CDPATH, and the shell assigns the expanded value. Bash also performs tilde expansion on words satisfying the conditions of variable assignments (as described above under PARAMETERS) when they appear as arguments to simple commands. Bash does not do this, except for the declaration commands listed above, when in posix mode. Parameter Expansion The `$' character introduces parameter expansion, command substitution, or arithmetic expansion. The parameter name or symbol to be expanded may be enclosed in braces, which are optional but serve to protect the variable to be expanded from characters immediately following it which could be interpreted as part of the name. When braces are used, the matching ending brace is the first `}' not escaped by a backslash or within a quoted string, and not within an embedded arithmetic expansion, command substitution, or parameter expansion. ${parameter} The value of parameter is substituted. The braces are required when parameter is a positional parameter with more than one digit, or when parameter is followed by a character which is not to be interpreted as part of its name. The parameter is a shell parameter as described above PARAMETERS) or an array reference (Arrays). If the first character of parameter is an exclamation point (!), and parameter is not a nameref, it introduces a level of indirection. Bash uses the value formed by expanding the rest of parameter as the new parameter; this is then expanded and that value is used in the rest of the expansion, rather than the expansion of the original parameter. This is known as indirect expansion. The value is subject to tilde expansion, parameter expansion, command substitution, and arithmetic expansion. If parameter is a nameref, this expands to the name of the parameter referenced by parameter instead of performing the complete indirect expansion. The exceptions to this are the expansions of ${!prefix*} and ${!name[@]} described below. The exclamation point must immediately follow the left brace in order to introduce indirection. In each of the cases below, word is subject to tilde expansion, parameter expansion, command substitution, and arithmetic expansion. When not performing substring expansion, using the forms documented below (e.g., :-), bash tests for a parameter that is unset or null. Omitting the colon results in a test only for a parameter that is unset. ${parameter:-word} Use Default Values. If parameter is unset or null, the expansion of word is substituted. Otherwise, the value of parameter is substituted. ${parameter:=word} Assign Default Values. If parameter is unset or null, the expansion of word is assigned to parameter. The value of parameter is then substituted. Positional parameters and special parameters may not be assigned to in this way. ${parameter:?word} Display Error if Null or Unset. If parameter is null or unset, the expansion of word (or a message to that effect if word is not present) is written to the standard error and the shell, if it is not interactive, exits. Otherwise, the value of parameter is substituted. ${parameter:+word} Use Alternate Value. If parameter is null or unset, nothing is substituted, otherwise the expansion of word is substituted. ${parameter:offset} ${parameter:offset:length} Substring Expansion. Expands to up to length characters of the value of parameter starting at the character specified by offset. If parameter is @ or *, an indexed array subscripted by @ or *, or an associative array name, the results differ as described below. If length is omitted, expands to the substring of the value of parameter starting at the character specified by offset and extending to the end of the value. length and offset are arithmetic expressions (see ARITHMETIC EVALUATION below). If offset evaluates to a number less than zero, the value is used as an offset in characters from the end of the value of parameter. If length evaluates to a number less than zero, it is interpreted as an offset in characters from the end of the value of parameter rather than a number of characters, and the expansion is the characters between offset and that result. Note that a negative offset must be separated from the colon by at least one space to avoid being confused with the :- expansion. If parameter is @ or *, the result is length positional parameters beginning at offset. A negative offset is taken relative to one greater than the greatest positional parameter, so an offset of -1 evaluates to the last positional parameter. It is an expansion error if length evaluates to a number less than zero. If parameter is an indexed array name subscripted by @ or *, the result is the length members of the array beginning with ${parameter[offset]}. A negative offset is taken relative to one greater than the maximum index of the specified array. It is an expansion error if length evaluates to a number less than zero. Substring expansion applied to an associative array produces undefined results. Substring indexing is zero-based unless the positional parameters are used, in which case the indexing starts at 1 by default. If offset is 0, and the positional parameters are used, $0 is prefixed to the list. ${!prefix*} ${!prefix@} Names matching prefix. Expands to the names of variables whose names begin with prefix, separated by the first character of the IFS special variable. When @ is used and the expansion appears within double quotes, each variable name expands to a separate word. ${!name[@]} ${!name[*]} List of array keys. If name is an array variable, expands to the list of array indices (keys) assigned in name. If name is not an array, expands to 0 if name is set and null otherwise. When @ is used and the expansion appears within double quotes, each key expands to a separate word. ${#parameter} Parameter length. The length in characters of the value of parameter is substituted. If parameter is * or @, the value substituted is the number of positional parameters. If parameter is an array name subscripted by * or @, the value substituted is the number of elements in the array. If parameter is an indexed array name subscripted by a negative number, that number is interpreted as relative to one greater than the maximum index of parameter, so negative indices count back from the end of the array, and an index of -1 references the last element. ${parameter#word} ${parameter##word} Remove matching prefix pattern. The word is expanded to produce a pattern just as in pathname expansion, and matched against the expanded value of parameter using the rules described under Pattern Matching below. If the pattern matches the beginning of the value of parameter, then the result of the expansion is the expanded value of parameter with the shortest matching pattern (the ``#'' case) or the longest matching pattern (the ``##'' case) deleted. If parameter is @ or *, the pattern removal operation is applied to each positional parameter in turn, and the expansion is the resultant list. If parameter is an array variable subscripted with @ or *, the pattern removal operation is applied to each member of the array in turn, and the expansion is the resultant list. ${parameter%word} ${parameter%%word} Remove matching suffix pattern. The word is expanded to produce a pattern just as in pathname expansion, and matched against the expanded value of parameter using the rules described under Pattern Matching below. If the pattern matches a trailing portion of the expanded value of parameter, then the result of the expansion is the expanded value of parameter with the shortest matching pattern (the ``%'' case) or the longest matching pattern (the ``%%'' case) deleted. If parameter is @ or *, the pattern removal operation is applied to each positional parameter in turn, and the expansion is the resultant list. If parameter is an array variable subscripted with @ or *, the pattern removal operation is applied to each member of the array in turn, and the expansion is the resultant list. ${parameter/pattern/string} ${parameter//pattern/string} ${parameter/#pattern/string} ${parameter/%pattern/string} Pattern substitution. The pattern is expanded to produce a pattern just as in pathname expansion. Parameter is expanded and the longest match of pattern against its value is replaced with string. string undergoes tilde expansion, parameter and variable expansion, arithmetic expansion, command and process substitution, and quote removal. The match is performed using the rules described under Pattern Matching below. In the first form above, only the first match is replaced. If there are two slashes separating parameter and pattern (the second form above), all matches of pattern are replaced with string. If pattern is preceded by # (the third form above), it must match at the beginning of the expanded value of parameter. If pattern is preceded by % (the fourth form above), it must match at the end of the expanded value of parameter. If the expansion of string is null, matches of pattern are deleted. If string is null, matches of pattern are deleted and the / following pattern may be omitted. If the patsub_replacement shell option is enabled using shopt, any unquoted instances of & in string are replaced with the matching portion of pattern. Quoting any part of string inhibits replacement in the expansion of the quoted portion, including replacement strings stored in shell variables. Backslash will escape & in string; the backslash is removed in order to permit a literal & in the replacement string. Backslash can also be used to escape a backslash; \\ results in a literal backslash in the replacement. Users should take care if string is double-quoted to avoid unwanted interactions between the backslash and double-quoting, since backslash has special meaning within double quotes. Pattern substitution performs the check for unquoted & after expanding string; shell programmers should quote any occurrences of & they want to be taken literally in the replacement and ensure any instances of & they want to be replaced are unquoted. If the nocasematch shell option is enabled, the match is performed without regard to the case of alphabetic characters. If parameter is @ or *, the substitution operation is applied to each positional parameter in turn, and the expansion is the resultant list. If parameter is an array variable subscripted with @ or *, the substitution operation is applied to each member of the array in turn, and the expansion is the resultant list. ${parameter^pattern} ${parameter^^pattern} ${parameter,pattern} ${parameter,,pattern} Case modification. This expansion modifies the case of alphabetic characters in parameter. The pattern is expanded to produce a pattern just as in pathname expansion. Each character in the expanded value of parameter is tested against pattern, and, if it matches the pattern, its case is converted. The pattern should not attempt to match more than one character. The ^ operator converts lowercase letters matching pattern to uppercase; the , operator converts matching uppercase letters to lowercase. The ^^ and ,, expansions convert each matched character in the expanded value; the ^ and , expansions match and convert only the first character in the expanded value. If pattern is omitted, it is treated like a ?, which matches every character. If parameter is @ or *, the case modification operation is applied to each positional parameter in turn, and the expansion is the resultant list. If parameter is an array variable subscripted with @ or *, the case modification operation is applied to each member of the array in turn, and the expansion is the resultant list. ${parameter@operator} Parameter transformation. The expansion is either a transformation of the value of parameter or information about parameter itself, depending on the value of operator. Each operator is a single letter: U The expansion is a string that is the value of parameter with lowercase alphabetic characters converted to uppercase. u The expansion is a string that is the value of parameter with the first character converted to uppercase, if it is alphabetic. L The expansion is a string that is the value of parameter with uppercase alphabetic characters converted to lowercase. Q The expansion is a string that is the value of parameter quoted in a format that can be reused as input. E The expansion is a string that is the value of parameter with backslash escape sequences expanded as with the $'...' quoting mechanism. P The expansion is a string that is the result of expanding the value of parameter as if it were a prompt string (see PROMPTING below). A The expansion is a string in the form of an assignment statement or declare command that, if evaluated, will recreate parameter with its attributes and value. K Produces a possibly-quoted version of the value of parameter, except that it prints the values of indexed and associative arrays as a sequence of quoted key-value pairs (see Arrays above). a The expansion is a string consisting of flag values representing parameter's attributes. k Like the K transformation, but expands the keys and values of indexed and associative arrays to separate words after word splitting. If parameter is @ or *, the operation is applied to each positional parameter in turn, and the expansion is the resultant list. If parameter is an array variable subscripted with @ or *, the operation is applied to each member of the array in turn, and the expansion is the resultant list. The result of the expansion is subject to word splitting and pathname expansion as described below. Command Substitution Command substitution allows the output of a command to replace the command name. There are two forms: $(command) or `command` Bash performs the expansion by executing command in a subshell environment and replacing the command substitution with the standard output of the command, with any trailing newlines deleted. Embedded newlines are not deleted, but they may be removed during word splitting. The command substitution $(cat file) can be replaced by the equivalent but faster $(< file). When the old-style backquote form of substitution is used, backslash retains its literal meaning except when followed by $, `, or \. The first backquote not preceded by a backslash terminates the command substitution. When using the $(command) form, all characters between the parentheses make up the command; none are treated specially. Command substitutions may be nested. To nest when using the backquoted form, escape the inner backquotes with backslashes. If the substitution appears within double quotes, word splitting and pathname expansion are not performed on the results. Arithmetic Expansion Arithmetic expansion allows the evaluation of an arithmetic expression and the substitution of the result. The format for arithmetic expansion is: $((expression)) The expression undergoes the same expansions as if it were within double quotes, but double quote characters in expression are not treated specially and are removed. All tokens in the expression undergo parameter and variable expansion, command substitution, and quote removal. The result is treated as the arithmetic expression to be evaluated. Arithmetic expansions may be nested. The evaluation is performed according to the rules listed below under ARITHMETIC EVALUATION. If expression is invalid, bash prints a message indicating failure and no substitution occurs. Process Substitution Process substitution allows a process's input or output to be referred to using a filename. It takes the form of <(list) or >(list). The process list is run asynchronously, and its input or output appears as a filename. This filename is passed as an argument to the current command as the result of the expansion. If the >(list) form is used, writing to the file will provide input for list. If the <(list) form is used, the file passed as an argument should be read to obtain the output of list. Process substitution is supported on systems that support named pipes (FIFOs) or the /dev/fd method of naming open files. When available, process substitution is performed simultaneously with parameter and variable expansion, command substitution, and arithmetic expansion. Word Splitting The shell scans the results of parameter expansion, command substitution, and arithmetic expansion that did not occur within double quotes for word splitting. The shell treats each character of IFS as a delimiter, and splits the results of the other expansions into words using these characters as field terminators. If IFS is unset, or its value is exactly <space><tab><newline>, the default, then sequences of <space>, <tab>, and <newline> at the beginning and end of the results of the previous expansions are ignored, and any sequence of IFS characters not at the beginning or end serves to delimit words. If IFS has a value other than the default, then sequences of the whitespace characters space, tab, and newline are ignored at the beginning and end of the word, as long as the whitespace character is in the value of IFS (an IFS whitespace character). Any character in IFS that is not IFS whitespace, along with any adjacent IFS whitespace characters, delimits a field. A sequence of IFS whitespace characters is also treated as a delimiter. If the value of IFS is null, no word splitting occurs. Explicit null arguments ("" or '') are retained and passed to commands as empty strings. Unquoted implicit null arguments, resulting from the expansion of parameters that have no values, are removed. If a parameter with no value is expanded within double quotes, a null argument results and is retained and passed to a command as an empty string. When a quoted null argument appears as part of a word whose expansion is non-null, the null argument is removed. That is, the word -d'' becomes -d after word splitting and null argument removal. Note that if no expansion occurs, no splitting is performed. Pathname Expansion After word splitting, unless the -f option has been set, bash scans each word for the characters *, ?, and [. If one of these characters appears, and is not quoted, then the word is regarded as a pattern, and replaced with an alphabetically sorted list of filenames matching the pattern (see Pattern Matching below). If no matching filenames are found, and the shell option nullglob is not enabled, the word is left unchanged. If the nullglob option is set, and no matches are found, the word is removed. If the failglob shell option is set, and no matches are found, an error message is printed and the command is not executed. If the shell option nocaseglob is enabled, the match is performed without regard to the case of alphabetic characters. When a pattern is used for pathname expansion, the character ``.'' at the start of a name or immediately following a slash must be matched explicitly, unless the shell option dotglob is set. In order to match the filenames ``.'' and ``..'', the pattern must begin with ``.'' (for example, ``.?''), even if dotglob is set. If the globskipdots shell option is enabled, the filenames ``.'' and ``..'' are never matched, even if the pattern begins with a ``.''. When not matching pathnames, the ``.'' character is not treated specially. When matching a pathname, the slash character must always be matched explicitly by a slash in the pattern, but in other matching contexts it can be matched by a special pattern character as described below under Pattern Matching. See the description of shopt below under SHELL BUILTIN COMMANDS for a description of the nocaseglob, nullglob, globskipdots, failglob, and dotglob shell options. The GLOBIGNORE shell variable may be used to restrict the set of file names matching a pattern. If GLOBIGNORE is set, each matching file name that also matches one of the patterns in GLOBIGNORE is removed from the list of matches. If the nocaseglob option is set, the matching against the patterns in GLOBIGNORE is performed without regard to case. The filenames ``.'' and ``..'' are always ignored when GLOBIGNORE is set and not null. However, setting GLOBIGNORE to a non-null value has the effect of enabling the dotglob shell option, so all other filenames beginning with a ``.'' will match. To get the old behavior of ignoring filenames beginning with a ``.'', make ``.*'' one of the patterns in GLOBIGNORE. The dotglob option is disabled when GLOBIGNORE is unset. The pattern matching honors the setting of the extglob shell option. Pattern Matching Any character that appears in a pattern, other than the special pattern characters described below, matches itself. The NUL character may not occur in a pattern. A backslash escapes the following character; the escaping backslash is discarded when matching. The special pattern characters must be quoted if they are to be matched literally. The special pattern characters have the following meanings: * Matches any string, including the null string. When the globstar shell option is enabled, and * is used in a pathname expansion context, two adjacent *s used as a single pattern will match all files and zero or more directories and subdirectories. If followed by a /, two adjacent *s will match only directories and subdirectories. ? Matches any single character. [...] Matches any one of the enclosed characters. A pair of characters separated by a hyphen denotes a range expression; any character that falls between those two characters, inclusive, using the current locale's collating sequence and character set, is matched. If the first character following the [ is a ! or a ^ then any character not enclosed is matched. The sorting order of characters in range expressions, and the characters included in the range, are determined by the current locale and the values of the LC_COLLATE or LC_ALL shell variables, if set. To obtain the traditional interpretation of range expressions, where [a-d] is equivalent to [abcd], set value of the LC_ALL shell variable to C, or enable the globasciiranges shell option. A - may be matched by including it as the first or last character in the set. A ] may be matched by including it as the first character in the set. Within [ and ], character classes can be specified using the syntax [:class:], where class is one of the following classes defined in the POSIX standard: alnum alpha ascii blank cntrl digit graph lower print punct space upper word xdigit A character class matches any character belonging to that class. The word character class matches letters, digits, and the character _. Within [ and ], an equivalence class can be specified using the syntax [=c=], which matches all characters with the same collation weight (as defined by the current locale) as the character c. Within [ and ], the syntax [.symbol.] matches the collating symbol symbol. If the extglob shell option is enabled using the shopt builtin, the shell recognizes several extended pattern matching operators. In the following description, a pattern-list is a list of one or more patterns separated by a |. Composite patterns may be formed using one or more of the following sub-patterns: ?(pattern-list) Matches zero or one occurrence of the given patterns *(pattern-list) Matches zero or more occurrences of the given patterns +(pattern-list) Matches one or more occurrences of the given patterns @(pattern-list) Matches one of the given patterns !(pattern-list) Matches anything except one of the given patterns Theextglob option changes the behavior of the parser, since the parentheses are normally treated as operators with syntactic meaning. To ensure that extended matching patterns are parsed correctly, make sure that extglob is enabled before parsing constructs containing the patterns, including shell functions and command substitutions. When matching filenames, the dotglob shell option determines the set of filenames that are tested: when dotglob is enabled, the set of filenames includes all files beginning with ``.'', but ``.'' and ``..'' must be matched by a pattern or sub-pattern that begins with a dot; when it is disabled, the set does not include any filenames beginning with ``.'' unless the pattern or sub- pattern begins with a ``.''. As above, ``.'' only has a special meaning when matching filenames. Complicated extended pattern matching against long strings is slow, especially when the patterns contain alternations and the strings contain multiple matches. Using separate matches against shorter strings, or using arrays of strings instead of a single long string, may be faster. Quote Removal After the preceding expansions, all unquoted occurrences of the characters \, ', and " that did not result from one of the above expansions are removed. REDIRECTION top Before a command is executed, its input and output may be redirected using a special notation interpreted by the shell. Redirection allows commands' file handles to be duplicated, opened, closed, made to refer to different files, and can change the files the command reads from and writes to. Redirection may also be used to modify file handles in the current shell execution environment. The following redirection operators may precede or appear anywhere within a simple command or may follow a command. Redirections are processed in the order they appear, from left to right. Each redirection that may be preceded by a file descriptor number may instead be preceded by a word of the form {varname}. In this case, for each redirection operator except >&- and <&-, the shell will allocate a file descriptor greater than or equal to 10 and assign it to varname. If >&- or <&- is preceded by {varname}, the value of varname defines the file descriptor to close. If {varname} is supplied, the redirection persists beyond the scope of the command, allowing the shell programmer to manage the file descriptor's lifetime manually. The varredir_close shell option manages this behavior. In the following descriptions, if the file descriptor number is omitted, and the first character of the redirection operator is <, the redirection refers to the standard input (file descriptor 0). If the first character of the redirection operator is >, the redirection refers to the standard output (file descriptor 1). The word following the redirection operator in the following descriptions, unless otherwise noted, is subjected to brace expansion, tilde expansion, parameter and variable expansion, command substitution, arithmetic expansion, quote removal, pathname expansion, and word splitting. If it expands to more than one word, bash reports an error. Note that the order of redirections is significant. For example, the command ls > dirlist 2>&1 directs both standard output and standard error to the file dirlist, while the command ls 2>&1 > dirlist directs only the standard output to file dirlist, because the standard error was duplicated from the standard output before the standard output was redirected to dirlist. Bash handles several filenames specially when they are used in redirections, as described in the following table. If the operating system on which bash is running provides these special files, bash will use them; otherwise it will emulate them internally with the behavior described below. /dev/fd/fd If fd is a valid integer, file descriptor fd is duplicated. /dev/stdin File descriptor 0 is duplicated. /dev/stdout File descriptor 1 is duplicated. /dev/stderr File descriptor 2 is duplicated. /dev/tcp/host/port If host is a valid hostname or Internet address, and port is an integer port number or service name, bash attempts to open the corresponding TCP socket. /dev/udp/host/port If host is a valid hostname or Internet address, and port is an integer port number or service name, bash attempts to open the corresponding UDP socket. A failure to open or create a file causes the redirection to fail. Redirections using file descriptors greater than 9 should be used with care, as they may conflict with file descriptors the shell uses internally. Redirecting Input Redirection of input causes the file whose name results from the expansion of word to be opened for reading on file descriptor n, or the standard input (file descriptor 0) if n is not specified. The general format for redirecting input is: [n]<word Redirecting Output Redirection of output causes the file whose name results from the expansion of word to be opened for writing on file descriptor n, or the standard output (file descriptor 1) if n is not specified. If the file does not exist it is created; if it does exist it is truncated to zero size. The general format for redirecting output is: [n]>word If the redirection operator is >, and the noclobber option to the set builtin has been enabled, the redirection will fail if the file whose name results from the expansion of word exists and is a regular file. If the redirection operator is >|, or the redirection operator is > and the noclobber option to the set builtin command is not enabled, the redirection is attempted even if the file named by word exists. Appending Redirected Output Redirection of output in this fashion causes the file whose name results from the expansion of word to be opened for appending on file descriptor n, or the standard output (file descriptor 1) if n is not specified. If the file does not exist it is created. The general format for appending output is: [n]>>word Redirecting Standard Output and Standard Error This construct allows both the standard output (file descriptor 1) and the standard error output (file descriptor 2) to be redirected to the file whose name is the expansion of word. There are two formats for redirecting standard output and standard error: &>word and >&word Of the two forms, the first is preferred. This is semantically equivalent to >word 2>&1 When using the second form, word may not expand to a number or -. If it does, other redirection operators apply (see Duplicating File Descriptors below) for compatibility reasons. Appending Standard Output and Standard Error This construct allows both the standard output (file descriptor 1) and the standard error output (file descriptor 2) to be appended to the file whose name is the expansion of word. The format for appending standard output and standard error is: &>>word This is semantically equivalent to >>word 2>&1 (see Duplicating File Descriptors below). Here Documents This type of redirection instructs the shell to read input from the current source until a line containing only delimiter (with no trailing blanks) is seen. All of the lines read up to that point are then used as the standard input (or file descriptor n if n is specified) for a command. The format of here-documents is: [n]<<[-]word here-document delimiter No parameter and variable expansion, command substitution, arithmetic expansion, or pathname expansion is performed on word. If any part of word is quoted, the delimiter is the result of quote removal on word, and the lines in the here-document are not expanded. If word is unquoted, all lines of the here-document are subjected to parameter expansion, command substitution, and arithmetic expansion, the character sequence \<newline> is ignored, and \ must be used to quote the characters \, $, and `. If the redirection operator is <<-, then all leading tab characters are stripped from input lines and the line containing delimiter. This allows here-documents within shell scripts to be indented in a natural fashion. Here Strings A variant of here documents, the format is: [n]<<<word The word undergoes tilde expansion, parameter and variable expansion, command substitution, arithmetic expansion, and quote removal. Pathname expansion and word splitting are not performed. The result is supplied as a single string, with a newline appended, to the command on its standard input (or file descriptor n if n is specified). Duplicating File Descriptors The redirection operator [n]<&word is used to duplicate input file descriptors. If word expands to one or more digits, the file descriptor denoted by n is made to be a copy of that file descriptor. If the digits in word do not specify a file descriptor open for input, a redirection error occurs. If word evaluates to -, file descriptor n is closed. If n is not specified, the standard input (file descriptor 0) is used. The operator [n]>&word is used similarly to duplicate output file descriptors. If n is not specified, the standard output (file descriptor 1) is used. If the digits in word do not specify a file descriptor open for output, a redirection error occurs. If word evaluates to -, file descriptor n is closed. As a special case, if n is omitted, and word does not expand to one or more digits or -, the standard output and standard error are redirected as described previously. Moving File Descriptors The redirection operator [n]<&digit- moves the file descriptor digit to file descriptor n, or the standard input (file descriptor 0) if n is not specified. digit is closed after being duplicated to n. Similarly, the redirection operator [n]>&digit- moves the file descriptor digit to file descriptor n, or the standard output (file descriptor 1) if n is not specified. Opening File Descriptors for Reading and Writing The redirection operator [n]<>word causes the file whose name is the expansion of word to be opened for both reading and writing on file descriptor n, or on file descriptor 0 if n is not specified. If the file does not exist, it is created. ALIASES top Aliases allow a string to be substituted for a word when it is used as the first word of a simple command. The shell maintains a list of aliases that may be set and unset with the alias and unalias builtin commands (see SHELL BUILTIN COMMANDS below). The first word of each simple command, if unquoted, is checked to see if it has an alias. If so, that word is replaced by the text of the alias. The characters /, $, `, and = and any of the shell metacharacters or quoting characters listed above may not appear in an alias name. The replacement text may contain any valid shell input, including shell metacharacters. The first word of the replacement text is tested for aliases, but a word that is identical to an alias being expanded is not expanded a second time. This means that one may alias ls to ls -F, for instance, and bash does not try to recursively expand the replacement text. If the last character of the alias value is a blank, then the next command word following the alias is also checked for alias expansion. Aliases are created and listed with the alias command, and removed with the unalias command. There is no mechanism for using arguments in the replacement text. If arguments are needed, use a shell function (see FUNCTIONS below). Aliases are not expanded when the shell is not interactive, unless the expand_aliases shell option is set using shopt (see the description of shopt under SHELL BUILTIN COMMANDS below). The rules concerning the definition and use of aliases are somewhat confusing. Bash always reads at least one complete line of input, and all lines that make up a compound command, before executing any of the commands on that line or the compound command. Aliases are expanded when a command is read, not when it is executed. Therefore, an alias definition appearing on the same line as another command does not take effect until the next line of input is read. The commands following the alias definition on that line are not affected by the new alias. This behavior is also an issue when functions are executed. Aliases are expanded when a function definition is read, not when the function is executed, because a function definition is itself a command. As a consequence, aliases defined in a function are not available until after that function is executed. To be safe, always put alias definitions on a separate line, and do not use alias in compound commands. For almost every purpose, aliases are superseded by shell functions. FUNCTIONS top A shell function, defined as described above under SHELL GRAMMAR, stores a series of commands for later execution. When the name of a shell function is used as a simple command name, the list of commands associated with that function name is executed. Functions are executed in the context of the current shell; no new process is created to interpret them (contrast this with the execution of a shell script). When a function is executed, the arguments to the function become the positional parameters during its execution. The special parameter # is updated to reflect the change. Special parameter 0 is unchanged. The first element of the FUNCNAME variable is set to the name of the function while the function is executing. All other aspects of the shell execution environment are identical between a function and its caller with these exceptions: the DEBUG and RETURN traps (see the description of the trap builtin under SHELL BUILTIN COMMANDS below) are not inherited unless the function has been given the trace attribute (see the description of the declare builtin below) or the -o functrace shell option has been enabled with the set builtin (in which case all functions inherit the DEBUG and RETURN traps), and the ERR trap is not inherited unless the -o errtrace shell option has been enabled. Variables local to the function may be declared with the local builtin command (local variables). Ordinarily, variables and their values are shared between the function and its caller. If a variable is declared local, the variable's visible scope is restricted to that function and its children (including the functions it calls). In the following description, the current scope is a currently- executing function. Previous scopes consist of that function's caller and so on, back to the "global" scope, where the shell is not executing any shell function. Consequently, a local variable at the current scope is a variable declared using the local or declare builtins in the function that is currently executing. Local variables "shadow" variables with the same name declared at previous scopes. For instance, a local variable declared in a function hides a global variable of the same name: references and assignments refer to the local variable, leaving the global variable unmodified. When the function returns, the global variable is once again visible. The shell uses dynamic scoping to control a variable's visibility within functions. With dynamic scoping, visible variables and their values are a result of the sequence of function calls that caused execution to reach the current function. The value of a variable that a function sees depends on its value within its caller, if any, whether that caller is the "global" scope or another shell function. This is also the value that a local variable declaration "shadows", and the value that is restored when the function returns. For example, if a variable var is declared as local in function func1, and func1 calls another function func2, references to var made from within func2 will resolve to the local variable var from func1, shadowing any global variable named var. The unset builtin also acts using the same dynamic scope: if a variable is local to the current scope, unset will unset it; otherwise the unset will refer to the variable found in any calling scope as described above. If a variable at the current local scope is unset, it will remain so (appearing as unset) until it is reset in that scope or until the function returns. Once the function returns, any instance of the variable at a previous scope will become visible. If the unset acts on a variable at a previous scope, any instance of a variable with that name that had been shadowed will become visible (see below how the localvar_unset shell option changes this behavior). The FUNCNEST variable, if set to a numeric value greater than 0, defines a maximum function nesting level. Function invocations that exceed the limit cause the entire command to abort. If the builtin command return is executed in a function, the function completes and execution resumes with the next command after the function call. Any command associated with the RETURN trap is executed before execution resumes. When a function completes, the values of the positional parameters and the special parameter # are restored to the values they had prior to the function's execution. Function names and definitions may be listed with the -f option to the declare or typeset builtin commands. The -F option to declare or typeset will list the function names only (and optionally the source file and line number, if the extdebug shell option is enabled). Functions may be exported so that child shell processes (those created when executing a separate shell invocation) automatically have them defined with the -f option to the export builtin. A function definition may be deleted using the -f option to the unset builtin. Functions may be recursive. The FUNCNEST variable may be used to limit the depth of the function call stack and restrict the number of function invocations. By default, no limit is imposed on the number of recursive calls. ARITHMETIC EVALUATION top The shell allows arithmetic expressions to be evaluated, under certain circumstances (see the let and declare builtin commands, the (( compound command, and Arithmetic Expansion). Evaluation is done in fixed-width integers with no check for overflow, though division by 0 is trapped and flagged as an error. The operators and their precedence, associativity, and values are the same as in the C language. The following list of operators is grouped into levels of equal-precedence operators. The levels are listed in order of decreasing precedence. id++ id-- variable post-increment and post-decrement - + unary minus and plus ++id --id variable pre-increment and pre-decrement ! ~ logical and bitwise negation ** exponentiation * / % multiplication, division, remainder + - addition, subtraction << >> left and right bitwise shifts <= >= < > comparison == != equality and inequality & bitwise AND ^ bitwise exclusive OR | bitwise OR && logical AND || logical OR expr?expr:expr conditional operator = *= /= %= += -= <<= >>= &= ^= |= assignment expr1 , expr2 comma Shell variables are allowed as operands; parameter expansion is performed before the expression is evaluated. Within an expression, shell variables may also be referenced by name without using the parameter expansion syntax. A shell variable that is null or unset evaluates to 0 when referenced by name without using the parameter expansion syntax. The value of a variable is evaluated as an arithmetic expression when it is referenced, or when a variable which has been given the integer attribute using declare -i is assigned a value. A null value evaluates to 0. A shell variable need not have its integer attribute turned on to be used in an expression. Integer constants follow the C language definition, without suffixes or character constants. Constants with a leading 0 are interpreted as octal numbers. A leading 0x or 0X denotes hexadecimal. Otherwise, numbers take the form [base#]n, where the optional base is a decimal number between 2 and 64 representing the arithmetic base, and n is a number in that base. If base# is omitted, then base 10 is used. When specifying n, if a non-digit is required, the digits greater than 9 are represented by the lowercase letters, the uppercase letters, @, and _, in that order. If base is less than or equal to 36, lowercase and uppercase letters may be used interchangeably to represent numbers between 10 and 35. Operators are evaluated in order of precedence. Sub-expressions in parentheses are evaluated first and may override the precedence rules above. CONDITIONAL EXPRESSIONS top Conditional expressions are used by the [[ compound command and the test and [ builtin commands to test file attributes and perform string and arithmetic comparisons. The test and [ commands determine their behavior based on the number of arguments; see the descriptions of those commands for any other command-specific actions. Expressions are formed from the following unary or binary primaries. Bash handles several filenames specially when they are used in expressions. If the operating system on which bash is running provides these special files, bash will use them; otherwise it will emulate them internally with this behavior: If any file argument to one of the primaries is of the form /dev/fd/n, then file descriptor n is checked. If the file argument to one of the primaries is one of /dev/stdin, /dev/stdout, or /dev/stderr, file descriptor 0, 1, or 2, respectively, is checked. Unless otherwise specified, primaries that operate on files follow symbolic links and operate on the target of the link, rather than the link itself. When used with [[, the < and > operators sort lexicographically using the current locale. The test command sorts using ASCII ordering. -a file True if file exists. -b file True if file exists and is a block special file. -c file True if file exists and is a character special file. -d file True if file exists and is a directory. -e file True if file exists. -f file True if file exists and is a regular file. -g file True if file exists and is set-group-id. -h file True if file exists and is a symbolic link. -k file True if file exists and its ``sticky'' bit is set. -p file True if file exists and is a named pipe (FIFO). -r file True if file exists and is readable. -s file True if file exists and has a size greater than zero. -t fd True if file descriptor fd is open and refers to a terminal. -u file True if file exists and its set-user-id bit is set. -w file True if file exists and is writable. -x file True if file exists and is executable. -G file True if file exists and is owned by the effective group id. -L file True if file exists and is a symbolic link. -N file True if file exists and has been modified since it was last read. -O file True if file exists and is owned by the effective user id. -S file True if file exists and is a socket. file1 -ef file2 True if file1 and file2 refer to the same device and inode numbers. file1 -nt file2 True if file1 is newer (according to modification date) than file2, or if file1 exists and file2 does not. file1 -ot file2 True if file1 is older than file2, or if file2 exists and file1 does not. -o optname True if the shell option optname is enabled. See the list of options under the description of the -o option to the set builtin below. -v varname True if the shell variable varname is set (has been assigned a value). -R varname True if the shell variable varname is set and is a name reference. -z string True if the length of string is zero. string -n string True if the length of string is non-zero. string1 == string2 string1 = string2 True if the strings are equal. = should be used with the test command for POSIX conformance. When used with the [[ command, this performs pattern matching as described above (Compound Commands). string1 != string2 True if the strings are not equal. string1 < string2 True if string1 sorts before string2 lexicographically. string1 > string2 True if string1 sorts after string2 lexicographically. arg1 OP arg2 OP is one of -eq, -ne, -lt, -le, -gt, or -ge. These arithmetic binary operators return true if arg1 is equal to, not equal to, less than, less than or equal to, greater than, or greater than or equal to arg2, respectively. Arg1 and arg2 may be positive or negative integers. When used with the [[ command, Arg1 and Arg2 are evaluated as arithmetic expressions (see ARITHMETIC EVALUATION above). SIMPLE COMMAND EXPANSION top When a simple command is executed, the shell performs the following expansions, assignments, and redirections, from left to right, in the following order. 1. The words that the parser has marked as variable assignments (those preceding the command name) and redirections are saved for later processing. 2. The words that are not variable assignments or redirections are expanded. If any words remain after expansion, the first word is taken to be the name of the command and the remaining words are the arguments. 3. Redirections are performed as described above under REDIRECTION. 4. The text after the = in each variable assignment undergoes tilde expansion, parameter expansion, command substitution, arithmetic expansion, and quote removal before being assigned to the variable. If no command name results, the variable assignments affect the current shell environment. In the case of such a command (one that consists only of assignment statements and redirections), assignment statements are performed before redirections. Otherwise, the variables are added to the environment of the executed command and do not affect the current shell environment. If any of the assignments attempts to assign a value to a readonly variable, an error occurs, and the command exits with a non-zero status. If no command name results, redirections are performed, but do not affect the current shell environment. A redirection error causes the command to exit with a non-zero status. If there is a command name left after expansion, execution proceeds as described below. Otherwise, the command exits. If one of the expansions contained a command substitution, the exit status of the command is the exit status of the last command substitution performed. If there were no command substitutions, the command exits with a status of zero. COMMAND EXECUTION top After a command has been split into words, if it results in a simple command and an optional list of arguments, the following actions are taken. If the command name contains no slashes, the shell attempts to locate it. If there exists a shell function by that name, that function is invoked as described above in FUNCTIONS. If the name does not match a function, the shell searches for it in the list of shell builtins. If a match is found, that builtin is invoked. If the name is neither a shell function nor a builtin, and contains no slashes, bash searches each element of the PATH for a directory containing an executable file by that name. Bash uses a hash table to remember the full pathnames of executable files (see hash under SHELL BUILTIN COMMANDS below). A full search of the directories in PATH is performed only if the command is not found in the hash table. If the search is unsuccessful, the shell searches for a defined shell function named command_not_found_handle. If that function exists, it is invoked in a separate execution environment with the original command and the original command's arguments as its arguments, and the function's exit status becomes the exit status of that subshell. If that function is not defined, the shell prints an error message and returns an exit status of 127. If the search is successful, or if the command name contains one or more slashes, the shell executes the named program in a separate execution environment. Argument 0 is set to the name given, and the remaining arguments to the command are set to the arguments given, if any. If this execution fails because the file is not in executable format, and the file is not a directory, it is assumed to be a shell script, a file containing shell commands, and the shell creates a new instance of itself to execute it. This subshell reinitializes itself, so that the effect is as if a new shell had been invoked to handle the script, with the exception that the locations of commands remembered by the parent (see hash below under SHELL BUILTIN COMMANDS) are retained by the child. If the program is a file beginning with #!, the remainder of the first line specifies an interpreter for the program. The shell executes the specified interpreter on operating systems that do not handle this executable format themselves. The arguments to the interpreter consist of a single optional argument following the interpreter name on the first line of the program, followed by the name of the program, followed by the command arguments, if any. COMMAND EXECUTION ENVIRONMENT top The shell has an execution environment, which consists of the following: open files inherited by the shell at invocation, as modified by redirections supplied to the exec builtin the current working directory as set by cd, pushd, or popd, or inherited by the shell at invocation the file creation mode mask as set by umask or inherited from the shell's parent current traps set by trap shell parameters that are set by variable assignment or with set or inherited from the shell's parent in the environment shell functions defined during execution or inherited from the shell's parent in the environment options enabled at invocation (either by default or with command-line arguments) or by set options enabled by shopt shell aliases defined with alias various process IDs, including those of background jobs, the value of $$, and the value of PPID When a simple command other than a builtin or shell function is to be executed, it is invoked in a separate execution environment that consists of the following. Unless otherwise noted, the values are inherited from the shell. the shell's open files, plus any modifications and additions specified by redirections to the command the current working directory the file creation mode mask shell variables and functions marked for export, along with variables exported for the command, passed in the environment traps caught by the shell are reset to the values inherited from the shell's parent, and traps ignored by the shell are ignored A command invoked in this separate environment cannot affect the shell's execution environment. A subshell is a copy of the shell process. Command substitution, commands grouped with parentheses, and asynchronous commands are invoked in a subshell environment that is a duplicate of the shell environment, except that traps caught by the shell are reset to the values that the shell inherited from its parent at invocation. Builtin commands that are invoked as part of a pipeline are also executed in a subshell environment. Changes made to the subshell environment cannot affect the shell's execution environment. Subshells spawned to execute command substitutions inherit the value of the -e option from the parent shell. When not in posix mode, bash clears the -e option in such subshells. If a command is followed by a & and job control is not active, the default standard input for the command is the empty file /dev/null. Otherwise, the invoked command inherits the file descriptors of the calling shell as modified by redirections. ENVIRONMENT top When a program is invoked it is given an array of strings called the environment. This is a list of name-value pairs, of the form name=value. The shell provides several ways to manipulate the environment. On invocation, the shell scans its own environment and creates a parameter for each name found, automatically marking it for export to child processes. Executed commands inherit the environment. The export and declare -x commands allow parameters and functions to be added to and deleted from the environment. If the value of a parameter in the environment is modified, the new value becomes part of the environment, replacing the old. The environment inherited by any executed command consists of the shell's initial environment, whose values may be modified in the shell, less any pairs removed by the unset command, plus any additions via the export and declare -x commands. The environment for any simple command or function may be augmented temporarily by prefixing it with parameter assignments, as described above in PARAMETERS. These assignment statements affect only the environment seen by that command. If the -k option is set (see the set builtin command below), then all parameter assignments are placed in the environment for a command, not just those that precede the command name. When bash invokes an external command, the variable _ is set to the full filename of the command and passed to that command in its environment. EXIT STATUS top The exit status of an executed command is the value returned by the waitpid system call or equivalent function. Exit statuses fall between 0 and 255, though, as explained below, the shell may use values above 125 specially. Exit statuses from shell builtins and compound commands are also limited to this range. Under certain circumstances, the shell will use special values to indicate specific failure modes. For the shell's purposes, a command which exits with a zero exit status has succeeded. An exit status of zero indicates success. A non-zero exit status indicates failure. When a command terminates on a fatal signal N, bash uses the value of 128+N as the exit status. If a command is not found, the child process created to execute it returns a status of 127. If a command is found but is not executable, the return status is 126. If a command fails because of an error during expansion or redirection, the exit status is greater than zero. Shell builtin commands return a status of 0 (true) if successful, and non-zero (false) if an error occurs while they execute. All builtins return an exit status of 2 to indicate incorrect usage, generally invalid options or missing arguments. The exit status of the last command is available in the special parameter $?. Bash itself returns the exit status of the last command executed, unless a syntax error occurs, in which case it exits with a non- zero value. See also the exit builtin command below. SIGNALS top When bash is interactive, in the absence of any traps, it ignores SIGTERM (so that kill 0 does not kill an interactive shell), and SIGINT is caught and handled (so that the wait builtin is interruptible). In all cases, bash ignores SIGQUIT. If job control is in effect, bash ignores SIGTTIN, SIGTTOU, and SIGTSTP. Non-builtin commands run by bash have signal handlers set to the values inherited by the shell from its parent. When job control is not in effect, asynchronous commands ignore SIGINT and SIGQUIT in addition to these inherited handlers. Commands run as a result of command substitution ignore the keyboard-generated job control signals SIGTTIN, SIGTTOU, and SIGTSTP. The shell exits by default upon receipt of a SIGHUP. Before exiting, an interactive shell resends the SIGHUP to all jobs, running or stopped. Stopped jobs are sent SIGCONT to ensure that they receive the SIGHUP. To prevent the shell from sending the signal to a particular job, it should be removed from the jobs table with the disown builtin (see SHELL BUILTIN COMMANDS below) or marked to not receive SIGHUP using disown -h. If the huponexit shell option has been set with shopt, bash sends a SIGHUP to all jobs when an interactive login shell exits. If bash is waiting for a command to complete and receives a signal for which a trap has been set, the trap will not be executed until the command completes. When bash is waiting for an asynchronous command via the wait builtin, the reception of a signal for which a trap has been set will cause the wait builtin to return immediately with an exit status greater than 128, immediately after which the trap is executed. When job control is not enabled, and bash is waiting for a foreground command to complete, the shell receives keyboard- generated signals such as SIGINT (usually generated by ^C) that users commonly intend to send to that command. This happens because the shell and the command are in the same process group as the terminal, and ^C sends SIGINT to all processes in that process group. When bash is running without job control enabled and receives SIGINT while waiting for a foreground command, it waits until that foreground command terminates and then decides what to do about the SIGINT: 1. If the command terminates due to the SIGINT, bash concludes that the user meant to end the entire script, and acts on the SIGINT (e.g., by running a SIGINT trap or exiting itself); 2. If the command does not terminate due to SIGINT, the program handled the SIGINT itself and did not treat it as a fatal signal. In that case, bash does not treat SIGINT as a fatal signal, either, instead assuming that the SIGINT was used as part of the program's normal operation (e.g., emacs uses it to abort editing commands) or deliberately discarded. However, bash will run any trap set on SIGINT, as it does with any other trapped signal it receives while it is waiting for the foreground command to complete, for compatibility. JOB CONTROL top Job control refers to the ability to selectively stop (suspend) the execution of processes and continue (resume) their execution at a later point. A user typically employs this facility via an interactive interface supplied jointly by the operating system kernel's terminal driver and bash. The shell associates a job with each pipeline. It keeps a table of currently executing jobs, which may be listed with the jobs command. When bash starts a job asynchronously (in the background), it prints a line that looks like: [1] 25647 indicating that this job is job number 1 and that the process ID of the last process in the pipeline associated with this job is 25647. All of the processes in a single pipeline are members of the same job. Bash uses the job abstraction as the basis for job control. To facilitate the implementation of the user interface to job control, the operating system maintains the notion of a current terminal process group ID. Members of this process group (processes whose process group ID is equal to the current terminal process group ID) receive keyboard-generated signals such as SIGINT. These processes are said to be in the foreground. Background processes are those whose process group ID differs from the terminal's; such processes are immune to keyboard-generated signals. Only foreground processes are allowed to read from or, if the user so specifies with stty tostop, write to the terminal. Background processes which attempt to read from (write to when stty tostop is in effect) the terminal are sent a SIGTTIN (SIGTTOU) signal by the kernel's terminal driver, which, unless caught, suspends the process. If the operating system on which bash is running supports job control, bash contains facilities to use it. Typing the suspend character (typically ^Z, Control-Z) while a process is running causes that process to be stopped and returns control to bash. Typing the delayed suspend character (typically ^Y, Control-Y) causes the process to be stopped when it attempts to read input from the terminal, and control to be returned to bash. The user may then manipulate the state of this job, using the bg command to continue it in the background, the fg command to continue it in the foreground, or the kill command to kill it. A ^Z takes effect immediately, and has the additional side effect of causing pending output and typeahead to be discarded. There are a number of ways to refer to a job in the shell. The character % introduces a job specification (jobspec). Job number n may be referred to as %n. A job may also be referred to using a prefix of the name used to start it, or using a substring that appears in its command line. For example, %ce refers to a stopped job whose command name begins with ce. If a prefix matches more than one job, bash reports an error. Using %?ce, on the other hand, refers to any job containing the string ce in its command line. If the substring matches more than one job, bash reports an error. The symbols %% and %+ refer to the shell's notion of the current job, which is the last job stopped while it was in the foreground or started in the background. The previous job may be referenced using %-. If there is only a single job, %+ and %- can both be used to refer to that job. In output pertaining to jobs (e.g., the output of the jobs command), the current job is always flagged with a +, and the previous job with a -. A single % (with no accompanying job specification) also refers to the current job. Simply naming a job can be used to bring it into the foreground: %1 is a synonym for ``fg %1'', bringing job 1 from the background into the foreground. Similarly, ``%1 &'' resumes job 1 in the background, equivalent to ``bg %1''. The shell learns immediately whenever a job changes state. Normally, bash waits until it is about to print a prompt before reporting changes in a job's status so as to not interrupt any other output. If the -b option to the set builtin command is enabled, bash reports such changes immediately. Any trap on SIGCHLD is executed for each child that exits. If an attempt to exit bash is made while jobs are stopped (or, if the checkjobs shell option has been enabled using the shopt builtin, running), the shell prints a warning message, and, if the checkjobs option is enabled, lists the jobs and their statuses. The jobs command may then be used to inspect their status. If a second attempt to exit is made without an intervening command, the shell does not print another warning, and any stopped jobs are terminated. When the shell is waiting for a job or process using the wait builtin, and job control is enabled, wait will return when the job changes state. The -f option causes wait to wait until the job or process terminates before returning. PROMPTING top When executing interactively, bash displays the primary prompt PS1 when it is ready to read a command, and the secondary prompt PS2 when it needs more input to complete a command. Bash displays PS0 after it reads a command but before executing it. Bash displays PS4 as described above before tracing each command when the -x option is enabled. Bash allows these prompt strings to be customized by inserting a number of backslash-escaped special characters that are decoded as follows: \a an ASCII bell character (07) \d the date in "Weekday Month Date" format (e.g., "Tue May 26") \D{format} the format is passed to strftime(3) and the result is inserted into the prompt string; an empty format results in a locale-specific time representation. The braces are required \e an ASCII escape character (033) \h the hostname up to the first `.' \H the hostname \j the number of jobs currently managed by the shell \l the basename of the shell's terminal device name \n newline \r carriage return \s the name of the shell, the basename of $0 (the portion following the final slash) \t the current time in 24-hour HH:MM:SS format \T the current time in 12-hour HH:MM:SS format \@ the current time in 12-hour am/pm format \A the current time in 24-hour HH:MM format \u the username of the current user \v the version of bash (e.g., 2.00) \V the release of bash, version + patch level (e.g., 2.00.0) \w the value of the PWD shell variable ($PWD), with $HOME abbreviated with a tilde (uses the value of the PROMPT_DIRTRIM variable) \W the basename of $PWD, with $HOME abbreviated with a tilde \! the history number of this command \# the command number of this command \$ if the effective UID is 0, a #, otherwise a $ \nnn the character corresponding to the octal number nnn \\ a backslash \[ begin a sequence of non-printing characters, which could be used to embed a terminal control sequence into the prompt \] end a sequence of non-printing characters The command number and the history number are usually different: the history number of a command is its position in the history list, which may include commands restored from the history file (see HISTORY below), while the command number is the position in the sequence of commands executed during the current shell session. After the string is decoded, it is expanded via parameter expansion, command substitution, arithmetic expansion, and quote removal, subject to the value of the promptvars shell option (see the description of the shopt command under SHELL BUILTIN COMMANDS below). This can have unwanted side effects if escaped portions of the string appear within command substitution or contain characters special to word expansion. READLINE top This is the library that handles reading input when using an interactive shell, unless the --noediting option is given at shell invocation. Line editing is also used when using the -e option to the read builtin. By default, the line editing commands are similar to those of Emacs. A vi-style line editing interface is also available. Line editing can be enabled at any time using the -o emacs or -o vi options to the set builtin (see SHELL BUILTIN COMMANDS below). To turn off line editing after the shell is running, use the +o emacs or +o vi options to the set builtin. Readline Notation In this section, the Emacs-style notation is used to denote keystrokes. Control keys are denoted by C-key, e.g., C-n means Control-N. Similarly, meta keys are denoted by M-key, so M-x means Meta-X. (On keyboards without a meta key, M-x means ESC x, i.e., press the Escape key then the x key. This makes ESC the meta prefix. The combination M-C-x means ESC-Control-x, or press the Escape key then hold the Control key while pressing the x key.) Readline commands may be given numeric arguments, which normally act as a repeat count. Sometimes, however, it is the sign of the argument that is significant. Passing a negative argument to a command that acts in the forward direction (e.g., kill-line) causes that command to act in a backward direction. Commands whose behavior with arguments deviates from this are noted below. When a command is described as killing text, the text deleted is saved for possible future retrieval (yanking). The killed text is saved in a kill ring. Consecutive kills cause the text to be accumulated into one unit, which can be yanked all at once. Commands which do not kill text separate the chunks of text on the kill ring. Readline Initialization Readline is customized by putting commands in an initialization file (the inputrc file). The name of this file is taken from the value of the INPUTRC variable. If that variable is unset, the default is ~/.inputrc. If that file does not exist or cannot be read, the ultimate default is /etc/inputrc. When a program which uses the readline library starts up, the initialization file is read, and the key bindings and variables are set. There are only a few basic constructs allowed in the readline initialization file. Blank lines are ignored. Lines beginning with a # are comments. Lines beginning with a $ indicate conditional constructs. Other lines denote key bindings and variable settings. The default key-bindings may be changed with an inputrc file. Other programs that use this library may add their own commands and bindings. For example, placing M-Control-u: universal-argument or C-Meta-u: universal-argument into the inputrc would make M-C-u execute the readline command universal-argument. The following symbolic character names are recognized: RUBOUT, DEL, ESC, LFD, NEWLINE, RET, RETURN, SPC, SPACE, and TAB. In addition to command names, readline allows keys to be bound to a string that is inserted when the key is pressed (a macro). Readline Key Bindings The syntax for controlling key bindings in the inputrc file is simple. All that is required is the name of the command or the text of a macro and a key sequence to which it should be bound. The name may be specified in one of two ways: as a symbolic key name, possibly with Meta- or Control- prefixes, or as a key sequence. When using the form keyname:function-name or macro, keyname is the name of a key spelled out in English. For example: Control-u: universal-argument Meta-Rubout: backward-kill-word Control-o: "> output" In the above example, C-u is bound to the function universal-argument, M-DEL is bound to the function backward-kill-word, and C-o is bound to run the macro expressed on the right hand side (that is, to insert the text ``> output'' into the line). In the second form, "keyseq":function-name or macro, keyseq differs from keyname above in that strings denoting an entire key sequence may be specified by placing the sequence within double quotes. Some GNU Emacs style key escapes can be used, as in the following example, but the symbolic character names are not recognized. "\C-u": universal-argument "\C-x\C-r": re-read-init-file "\e[11~": "Function Key 1" In this example, C-u is again bound to the function universal-argument. C-x C-r is bound to the function re-read-init-file, and ESC [ 1 1 ~ is bound to insert the text ``Function Key 1''. The full set of GNU Emacs style escape sequences is \C- control prefix \M- meta prefix \e an escape character \\ backslash \" literal " \' literal ' In addition to the GNU Emacs style escape sequences, a second set of backslash escapes is available: \a alert (bell) \b backspace \d delete \f form feed \n newline \r carriage return \t horizontal tab \v vertical tab \nnn the eight-bit character whose value is the octal value nnn (one to three digits) \xHH the eight-bit character whose value is the hexadecimal value HH (one or two hex digits) When entering the text of a macro, single or double quotes must be used to indicate a macro definition. Unquoted text is assumed to be a function name. In the macro body, the backslash escapes described above are expanded. Backslash will quote any other character in the macro text, including " and '. Bash allows the current readline key bindings to be displayed or modified with the bind builtin command. The editing mode may be switched during interactive use by using the -o option to the set builtin command (see SHELL BUILTIN COMMANDS below). Readline Variables Readline has variables that can be used to further customize its behavior. A variable may be set in the inputrc file with a statement of the form set variable-name value or using the bind builtin command (see SHELL BUILTIN COMMANDS below). Except where noted, readline variables can take the values On or Off (without regard to case). Unrecognized variable names are ignored. When a variable value is read, empty or null values, "on" (case-insensitive), and "1" are equivalent to On. All other values are equivalent to Off. The variables and their default values are: active-region-start-color A string variable that controls the text color and background when displaying the text in the active region (see the description of enable-active-region below). This string must not take up any physical character positions on the display, so it should consist only of terminal escape sequences. It is output to the terminal before displaying the text in the active region. This variable is reset to the default value whenever the terminal type changes. The default value is the string that puts the terminal in standout mode, as obtained from the terminal's terminfo description. A sample value might be "\e[01;33m". active-region-end-color A string variable that "undoes" the effects of active-region-start-color and restores "normal" terminal display appearance after displaying text in the active region. This string must not take up any physical character positions on the display, so it should consist only of terminal escape sequences. It is output to the terminal after displaying the text in the active region. This variable is reset to the default value whenever the terminal type changes. The default value is the string that restores the terminal from standout mode, as obtained from the terminal's terminfo description. A sample value might be "\e[0m". bell-style (audible) Controls what happens when readline wants to ring the terminal bell. If set to none, readline never rings the bell. If set to visible, readline uses a visible bell if one is available. If set to audible, readline attempts to ring the terminal's bell. bind-tty-special-chars (On) If set to On, readline attempts to bind the control characters treated specially by the kernel's terminal driver to their readline equivalents. blink-matching-paren (Off) If set to On, readline attempts to briefly move the cursor to an opening parenthesis when a closing parenthesis is inserted. colored-completion-prefix (Off) If set to On, when listing completions, readline displays the common prefix of the set of possible completions using a different color. The color definitions are taken from the value of the LS_COLORS environment variable. If there is a color definition in $LS_COLORS for the custom suffix "readline-colored-completion-prefix", readline uses this color for the common prefix instead of its default. colored-stats (Off) If set to On, readline displays possible completions using different colors to indicate their file type. The color definitions are taken from the value of the LS_COLORS environment variable. comment-begin (``#'') The string that is inserted when the readline insert-comment command is executed. This command is bound to M-# in emacs mode and to # in vi command mode. completion-display-width (-1) The number of screen columns used to display possible matches when performing completion. The value is ignored if it is less than 0 or greater than the terminal screen width. A value of 0 will cause matches to be displayed one per line. The default value is -1. completion-ignore-case (Off) If set to On, readline performs filename matching and completion in a case-insensitive fashion. completion-map-case (Off) If set to On, and completion-ignore-case is enabled, readline treats hyphens (-) and underscores (_) as equivalent when performing case-insensitive filename matching and completion. completion-prefix-display-length(0) The length in characters of the common prefix of a list of possible completions that is displayed without modification. When set to a value greater than zero, common prefixes longer than this value are replaced with an ellipsis when displaying possible completions. completion-query-items (100) This determines when the user is queried about viewing the number of possible completions generated by the possible-completions command. It may be set to any integer value greater than or equal to zero. If the number of possible completions is greater than or equal to the value of this variable, readline will ask whether or not the user wishes to view them; otherwise they are simply listed on the terminal. A zero value means readline should never ask; negative values are treated as zero. convert-meta (On) If set to On, readline will convert characters with the eighth bit set to an ASCII key sequence by stripping the eighth bit and prefixing an escape character (in effect, using escape as the meta prefix). The default is On, but readline will set it to Off if the locale contains eight- bit characters. This variable is dependent on the LC_CTYPE locale category, and may change if the locale is changed. disable-completion (Off) If set to On, readline will inhibit word completion. Completion characters will be inserted into the line as if they had been mapped to self-insert. echo-control-characters (On) When set to On, on operating systems that indicate they support it, readline echoes a character corresponding to a signal generated from the keyboard. editing-mode (emacs) Controls whether readline begins with a set of key bindings similar to Emacs or vi. editing-mode can be set to either emacs or vi. emacs-mode-string (@) If the show-mode-in-prompt variable is enabled, this string is displayed immediately before the last line of the primary prompt when emacs editing mode is active. The value is expanded like a key binding, so the standard set of meta- and control prefixes and backslash escape sequences is available. Use the \1 and \2 escapes to begin and end sequences of non-printing characters, which can be used to embed a terminal control sequence into the mode string. enable-active-region (On) The point is the current cursor position, and mark refers to a saved cursor position. The text between the point and mark is referred to as the region. When this variable is set to On, readline allows certain commands to designate the region as active. When the region is active, readline highlights the text in the region using the value of the active-region-start-color, which defaults to the string that enables the terminal's standout mode. The active region shows the text inserted by bracketed- paste and any matching text found by incremental and non- incremental history searches. enable-bracketed-paste (On) When set to On, readline configures the terminal to insert each paste into the editing buffer as a single string of characters, instead of treating each character as if it had been read from the keyboard. This prevents readline from executing any editing commands bound to key sequences appearing in the pasted text. enable-keypad (Off) When set to On, readline will try to enable the application keypad when it is called. Some systems need this to enable the arrow keys. enable-meta-key (On) When set to On, readline will try to enable any meta modifier key the terminal claims to support when it is called. On many terminals, the meta key is used to send eight-bit characters. expand-tilde (Off) If set to On, tilde expansion is performed when readline attempts word completion. history-preserve-point (Off) If set to On, the history code attempts to place point at the same location on each history line retrieved with previous-history or next-history. history-size (unset) Set the maximum number of history entries saved in the history list. If set to zero, any existing history entries are deleted and no new entries are saved. If set to a value less than zero, the number of history entries is not limited. By default, the number of history entries is set to the value of the HISTSIZE shell variable. If an attempt is made to set history-size to a non-numeric value, the maximum number of history entries will be set to 500. horizontal-scroll-mode (Off) When set to On, makes readline use a single line for display, scrolling the input horizontally on a single screen line when it becomes longer than the screen width rather than wrapping to a new line. This setting is automatically enabled for terminals of height 1. input-meta (Off) If set to On, readline will enable eight-bit input (that is, it will not strip the eighth bit from the characters it reads), regardless of what the terminal claims it can support. The name meta-flag is a synonym for this variable. The default is Off, but readline will set it to On if the locale contains eight-bit characters. This variable is dependent on the LC_CTYPE locale category, and may change if the locale is changed. isearch-terminators (``C-[C-J'') The string of characters that should terminate an incremental search without subsequently executing the character as a command. If this variable has not been given a value, the characters ESC and C-J will terminate an incremental search. keymap (emacs) Set the current readline keymap. The set of valid keymap names is emacs, emacs-standard, emacs-meta, emacs-ctlx, vi, vi-command, and vi-insert. vi is equivalent to vi-command; emacs is equivalent to emacs-standard. The default value is emacs; the value of editing-mode also affects the default keymap. keyseq-timeout (500) Specifies the duration readline will wait for a character when reading an ambiguous key sequence (one that can form a complete key sequence using the input read so far, or can take additional input to complete a longer key sequence). If no input is received within the timeout, readline will use the shorter but complete key sequence. The value is specified in milliseconds, so a value of 1000 means that readline will wait one second for additional input. If this variable is set to a value less than or equal to zero, or to a non-numeric value, readline will wait until another key is pressed to decide which key sequence to complete. mark-directories (On) If set to On, completed directory names have a slash appended. mark-modified-lines (Off) If set to On, history lines that have been modified are displayed with a preceding asterisk (*). mark-symlinked-directories (Off) If set to On, completed names which are symbolic links to directories have a slash appended (subject to the value of mark-directories). match-hidden-files (On) This variable, when set to On, causes readline to match files whose names begin with a `.' (hidden files) when performing filename completion. If set to Off, the leading `.' must be supplied by the user in the filename to be completed. menu-complete-display-prefix (Off) If set to On, menu completion displays the common prefix of the list of possible completions (which may be empty) before cycling through the list. output-meta (Off) If set to On, readline will display characters with the eighth bit set directly rather than as a meta-prefixed escape sequence. The default is Off, but readline will set it to On if the locale contains eight-bit characters. This variable is dependent on the LC_CTYPE locale category, and may change if the locale is changed. page-completions (On) If set to On, readline uses an internal more-like pager to display a screenful of possible completions at a time. print-completions-horizontally (Off) If set to On, readline will display completions with matches sorted horizontally in alphabetical order, rather than down the screen. revert-all-at-newline (Off) If set to On, readline will undo all changes to history lines before returning when accept-line is executed. By default, history lines may be modified and retain individual undo lists across calls to readline. show-all-if-ambiguous (Off) This alters the default behavior of the completion functions. If set to On, words which have more than one possible completion cause the matches to be listed immediately instead of ringing the bell. show-all-if-unmodified (Off) This alters the default behavior of the completion functions in a fashion similar to show-all-if-ambiguous. If set to On, words which have more than one possible completion without any possible partial completion (the possible completions don't share a common prefix) cause the matches to be listed immediately instead of ringing the bell. show-mode-in-prompt (Off) If set to On, add a string to the beginning of the prompt indicating the editing mode: emacs, vi command, or vi insertion. The mode strings are user-settable (e.g., emacs-mode-string). skip-completed-text (Off) If set to On, this alters the default completion behavior when inserting a single match into the line. It's only active when performing completion in the middle of a word. If enabled, readline does not insert characters from the completion that match characters after point in the word being completed, so portions of the word following the cursor are not duplicated. vi-cmd-mode-string ((cmd)) If the show-mode-in-prompt variable is enabled, this string is displayed immediately before the last line of the primary prompt when vi editing mode is active and in command mode. The value is expanded like a key binding, so the standard set of meta- and control prefixes and backslash escape sequences is available. Use the \1 and \2 escapes to begin and end sequences of non-printing characters, which can be used to embed a terminal control sequence into the mode string. vi-ins-mode-string ((ins)) If the show-mode-in-prompt variable is enabled, this string is displayed immediately before the last line of the primary prompt when vi editing mode is active and in insertion mode. The value is expanded like a key binding, so the standard set of meta- and control prefixes and backslash escape sequences is available. Use the \1 and \2 escapes to begin and end sequences of non-printing characters, which can be used to embed a terminal control sequence into the mode string. visible-stats (Off) If set to On, a character denoting a file's type as reported by stat(2) is appended to the filename when listing possible completions. Readline Conditional Constructs Readline implements a facility similar in spirit to the conditional compilation features of the C preprocessor which allows key bindings and variable settings to be performed as the result of tests. There are four parser directives used. $if The $if construct allows bindings to be made based on the editing mode, the terminal being used, or the application using readline. The text of the test, after any comparison operator, extends to the end of the line; unless otherwise noted, no characters are required to isolate it. mode The mode= form of the $if directive is used to test whether readline is in emacs or vi mode. This may be used in conjunction with the set keymap command, for instance, to set bindings in the emacs-standard and emacs-ctlx keymaps only if readline is starting out in emacs mode. term The term= form may be used to include terminal- specific key bindings, perhaps to bind the key sequences output by the terminal's function keys. The word on the right side of the = is tested against both the full name of the terminal and the portion of the terminal name before the first -. This allows sun to match both sun and sun-cmd, for instance. version The version test may be used to perform comparisons against specific readline versions. The version expands to the current readline version. The set of comparison operators includes =, (and ==), !=, <=, >=, <, and >. The version number supplied on the right side of the operator consists of a major version number, an optional decimal point, and an optional minor version (e.g., 7.1). If the minor version is omitted, it is assumed to be 0. The operator may be separated from the string version and from the version number argument by whitespace. application The application construct is used to include application-specific settings. Each program using the readline library sets the application name, and an initialization file can test for a particular value. This could be used to bind key sequences to functions useful for a specific program. For instance, the following command adds a key sequence that quotes the current or previous word in bash: $if Bash # Quote the current or previous word "\C-xq": "\eb\"\ef\"" $endif variable The variable construct provides simple equality tests for readline variables and values. The permitted comparison operators are =, ==, and !=. The variable name must be separated from the comparison operator by whitespace; the operator may be separated from the value on the right hand side by whitespace. Both string and boolean variables may be tested. Boolean variables must be tested against the values on and off. $endif This command, as seen in the previous example, terminates an $if command. $else Commands in this branch of the $if directive are executed if the test fails. $include This directive takes a single filename as an argument and reads commands and bindings from that file. For example, the following directive would read /etc/inputrc: $include /etc/inputrc Searching Readline provides commands for searching through the command history (see HISTORY below) for lines containing a specified string. There are two search modes: incremental and non- incremental. Incremental searches begin before the user has finished typing the search string. As each character of the search string is typed, readline displays the next entry from the history matching the string typed so far. An incremental search requires only as many characters as needed to find the desired history entry. The characters present in the value of the isearch-terminators variable are used to terminate an incremental search. If that variable has not been assigned a value the Escape and Control-J characters will terminate an incremental search. Control-G will abort an incremental search and restore the original line. When the search is terminated, the history entry containing the search string becomes the current line. To find other matching entries in the history list, type Control- S or Control-R as appropriate. This will search backward or forward in the history for the next entry matching the search string typed so far. Any other key sequence bound to a readline command will terminate the search and execute that command. For instance, a newline will terminate the search and accept the line, thereby executing the command from the history list. Readline remembers the last incremental search string. If two Control-Rs are typed without any intervening characters defining a new search string, any remembered search string is used. Non-incremental searches read the entire search string before starting to search for matching history lines. The search string may be typed by the user or be part of the contents of the current line. Readline Command Names The following is a list of the names of the commands and the default key sequences to which they are bound. Command names without an accompanying key sequence are unbound by default. In the following descriptions, point refers to the current cursor position, and mark refers to a cursor position saved by the set-mark command. The text between the point and mark is referred to as the region. Commands for Moving beginning-of-line (C-a) Move to the start of the current line. end-of-line (C-e) Move to the end of the line. forward-char (C-f) Move forward a character. backward-char (C-b) Move back a character. forward-word (M-f) Move forward to the end of the next word. Words are composed of alphanumeric characters (letters and digits). backward-word (M-b) Move back to the start of the current or previous word. Words are composed of alphanumeric characters (letters and digits). shell-forward-word Move forward to the end of the next word. Words are delimited by non-quoted shell metacharacters. shell-backward-word Move back to the start of the current or previous word. Words are delimited by non-quoted shell metacharacters. previous-screen-line Attempt to move point to the same physical screen column on the previous physical screen line. This will not have the desired effect if the current readline line does not take up more than one physical line or if point is not greater than the length of the prompt plus the screen width. next-screen-line Attempt to move point to the same physical screen column on the next physical screen line. This will not have the desired effect if the current readline line does not take up more than one physical line or if the length of the current readline line is not greater than the length of the prompt plus the screen width. clear-display (M-C-l) Clear the screen and, if possible, the terminal's scrollback buffer, then redraw the current line, leaving the current line at the top of the screen. clear-screen (C-l) Clear the screen, then redraw the current line, leaving the current line at the top of the screen. With an argument, refresh the current line without clearing the screen. redraw-current-line Refresh the current line. Commands for Manipulating the History accept-line (Newline, Return) Accept the line regardless of where the cursor is. If this line is non-empty, add it to the history list according to the state of the HISTCONTROL variable. If the line is a modified history line, then restore the history line to its original state. previous-history (C-p) Fetch the previous command from the history list, moving back in the list. next-history (C-n) Fetch the next command from the history list, moving forward in the list. beginning-of-history (M-<) Move to the first line in the history. end-of-history (M->) Move to the end of the input history, i.e., the line currently being entered. operate-and-get-next (C-o) Accept the current line for execution and fetch the next line relative to the current line from the history for editing. A numeric argument, if supplied, specifies the history entry to use instead of the current line. fetch-history With a numeric argument, fetch that entry from the history list and make it the current line. Without an argument, move back to the first entry in the history list. reverse-search-history (C-r) Search backward starting at the current line and moving `up' through the history as necessary. This is an incremental search. forward-search-history (C-s) Search forward starting at the current line and moving `down' through the history as necessary. This is an incremental search. non-incremental-reverse-search-history (M-p) Search backward through the history starting at the current line using a non-incremental search for a string supplied by the user. non-incremental-forward-search-history (M-n) Search forward through the history using a non-incremental search for a string supplied by the user. history-search-forward Search forward through the history for the string of characters between the start of the current line and the point. This is a non-incremental search. history-search-backward Search backward through the history for the string of characters between the start of the current line and the point. This is a non-incremental search. history-substring-search-backward Search backward through the history for the string of characters between the start of the current line and the current cursor position (the point). The search string may match anywhere in a history line. This is a non- incremental search. history-substring-search-forward Search forward through the history for the string of characters between the start of the current line and the point. The search string may match anywhere in a history line. This is a non-incremental search. yank-nth-arg (M-C-y) Insert the first argument to the previous command (usually the second word on the previous line) at point. With an argument n, insert the nth word from the previous command (the words in the previous command begin with word 0). A negative argument inserts the nth word from the end of the previous command. Once the argument n is computed, the argument is extracted as if the "!n" history expansion had been specified. yank-last-arg (M-., M-_) Insert the last argument to the previous command (the last word of the previous history entry). With a numeric argument, behave exactly like yank-nth-arg. Successive calls to yank-last-arg move back through the history list, inserting the last word (or the word specified by the argument to the first call) of each line in turn. Any numeric argument supplied to these successive calls determines the direction to move through the history. A negative argument switches the direction through the history (back or forward). The history expansion facilities are used to extract the last word, as if the "!$" history expansion had been specified. shell-expand-line (M-C-e) Expand the line as the shell does. This performs alias and history expansion as well as all of the shell word expansions. See HISTORY EXPANSION below for a description of history expansion. history-expand-line (M-^) Perform history expansion on the current line. See HISTORY EXPANSION below for a description of history expansion. magic-space Perform history expansion on the current line and insert a space. See HISTORY EXPANSION below for a description of history expansion. alias-expand-line Perform alias expansion on the current line. See ALIASES above for a description of alias expansion. history-and-alias-expand-line Perform history and alias expansion on the current line. insert-last-argument (M-., M-_) A synonym for yank-last-arg. edit-and-execute-command (C-x C-e) Invoke an editor on the current command line, and execute the result as shell commands. Bash attempts to invoke $VISUAL, $EDITOR, and emacs as the editor, in that order. Commands for Changing Text end-of-file (usually C-d) The character indicating end-of-file as set, for example, by ``stty''. If this character is read when there are no characters on the line, and point is at the beginning of the line, readline interprets it as the end of input and returns EOF. delete-char (C-d) Delete the character at point. If this function is bound to the same character as the tty EOF character, as C-d commonly is, see above for the effects. backward-delete-char (Rubout) Delete the character behind the cursor. When given a numeric argument, save the deleted text on the kill ring. forward-backward-delete-char Delete the character under the cursor, unless the cursor is at the end of the line, in which case the character behind the cursor is deleted. quoted-insert (C-q, C-v) Add the next character typed to the line verbatim. This is how to insert characters like C-q, for example. tab-insert (C-v TAB) Insert a tab character. self-insert (a, b, A, 1, !, ...) Insert the character typed. transpose-chars (C-t) Drag the character before point forward over the character at point, moving point forward as well. If point is at the end of the line, then this transposes the two characters before point. Negative arguments have no effect. transpose-words (M-t) Drag the word before point past the word after point, moving point over that word as well. If point is at the end of the line, this transposes the last two words on the line. upcase-word (M-u) Uppercase the current (or following) word. With a negative argument, uppercase the previous word, but do not move point. downcase-word (M-l) Lowercase the current (or following) word. With a negative argument, lowercase the previous word, but do not move point. capitalize-word (M-c) Capitalize the current (or following) word. With a negative argument, capitalize the previous word, but do not move point. overwrite-mode Toggle overwrite mode. With an explicit positive numeric argument, switches to overwrite mode. With an explicit non-positive numeric argument, switches to insert mode. This command affects only emacs mode; vi mode does overwrite differently. Each call to readline() starts in insert mode. In overwrite mode, characters bound to self-insert replace the text at point rather than pushing the text to the right. Characters bound to backward-delete-char replace the character before point with a space. By default, this command is unbound. Killing and Yanking kill-line (C-k) Kill the text from point to the end of the line. backward-kill-line (C-x Rubout) Kill backward to the beginning of the line. unix-line-discard (C-u) Kill backward from point to the beginning of the line. The killed text is saved on the kill-ring. kill-whole-line Kill all characters on the current line, no matter where point is. kill-word (M-d) Kill from point to the end of the current word, or if between words, to the end of the next word. Word boundaries are the same as those used by forward-word. backward-kill-word (M-Rubout) Kill the word behind point. Word boundaries are the same as those used by backward-word. shell-kill-word Kill from point to the end of the current word, or if between words, to the end of the next word. Word boundaries are the same as those used by shell-forward-word. shell-backward-kill-word Kill the word behind point. Word boundaries are the same as those used by shell-backward-word. unix-word-rubout (C-w) Kill the word behind point, using white space as a word boundary. The killed text is saved on the kill-ring. unix-filename-rubout Kill the word behind point, using white space and the slash character as the word boundaries. The killed text is saved on the kill-ring. delete-horizontal-space (M-\) Delete all spaces and tabs around point. kill-region Kill the text in the current region. copy-region-as-kill Copy the text in the region to the kill buffer. copy-backward-word Copy the word before point to the kill buffer. The word boundaries are the same as backward-word. copy-forward-word Copy the word following point to the kill buffer. The word boundaries are the same as forward-word. yank (C-y) Yank the top of the kill ring into the buffer at point. yank-pop (M-y) Rotate the kill ring, and yank the new top. Only works following yank or yank-pop. Numeric Arguments digit-argument (M-0, M-1, ..., M--) Add this digit to the argument already accumulating, or start a new argument. M-- starts a negative argument. universal-argument This is another way to specify an argument. If this command is followed by one or more digits, optionally with a leading minus sign, those digits define the argument. If the command is followed by digits, executing universal-argument again ends the numeric argument, but is otherwise ignored. As a special case, if this command is immediately followed by a character that is neither a digit nor minus sign, the argument count for the next command is multiplied by four. The argument count is initially one, so executing this function the first time makes the argument count four, a second time makes the argument count sixteen, and so on. Completing complete (TAB) Attempt to perform completion on the text before point. Bash attempts completion treating the text as a variable (if the text begins with $), username (if the text begins with ~), hostname (if the text begins with @), or command (including aliases and functions) in turn. If none of these produces a match, filename completion is attempted. possible-completions (M-?) List the possible completions of the text before point. insert-completions (M-*) Insert all completions of the text before point that would have been generated by possible-completions. menu-complete Similar to complete, but replaces the word to be completed with a single match from the list of possible completions. Repeated execution of menu-complete steps through the list of possible completions, inserting each match in turn. At the end of the list of completions, the bell is rung (subject to the setting of bell-style) and the original text is restored. An argument of n moves n positions forward in the list of matches; a negative argument may be used to move backward through the list. This command is intended to be bound to TAB, but is unbound by default. menu-complete-backward Identical to menu-complete, but moves backward through the list of possible completions, as if menu-complete had been given a negative argument. This command is unbound by default. delete-char-or-list Deletes the character under the cursor if not at the beginning or end of the line (like delete-char). If at the end of the line, behaves identically to possible-completions. This command is unbound by default. complete-filename (M-/) Attempt filename completion on the text before point. possible-filename-completions (C-x /) List the possible completions of the text before point, treating it as a filename. complete-username (M-~) Attempt completion on the text before point, treating it as a username. possible-username-completions (C-x ~) List the possible completions of the text before point, treating it as a username. complete-variable (M-$) Attempt completion on the text before point, treating it as a shell variable. possible-variable-completions (C-x $) List the possible completions of the text before point, treating it as a shell variable. complete-hostname (M-@) Attempt completion on the text before point, treating it as a hostname. possible-hostname-completions (C-x @) List the possible completions of the text before point, treating it as a hostname. complete-command (M-!) Attempt completion on the text before point, treating it as a command name. Command completion attempts to match the text against aliases, reserved words, shell functions, shell builtins, and finally executable filenames, in that order. possible-command-completions (C-x !) List the possible completions of the text before point, treating it as a command name. dynamic-complete-history (M-TAB) Attempt completion on the text before point, comparing the text against lines from the history list for possible completion matches. dabbrev-expand Attempt menu completion on the text before point, comparing the text against lines from the history list for possible completion matches. complete-into-braces (M-{) Perform filename completion and insert the list of possible completions enclosed within braces so the list is available to the shell (see Brace Expansion above). Keyboard Macros start-kbd-macro (C-x () Begin saving the characters typed into the current keyboard macro. end-kbd-macro (C-x )) Stop saving the characters typed into the current keyboard macro and store the definition. call-last-kbd-macro (C-x e) Re-execute the last keyboard macro defined, by making the characters in the macro appear as if typed at the keyboard. print-last-kbd-macro () Print the last keyboard macro defined in a format suitable for the inputrc file. Miscellaneous re-read-init-file (C-x C-r) Read in the contents of the inputrc file, and incorporate any bindings or variable assignments found there. abort (C-g) Abort the current editing command and ring the terminal's bell (subject to the setting of bell-style). do-lowercase-version (M-A, M-B, M-x, ...) If the metafied character x is uppercase, run the command that is bound to the corresponding metafied lowercase character. The behavior is undefined if x is already lowercase. prefix-meta (ESC) Metafy the next character typed. ESC f is equivalent to Meta-f. undo (C-_, C-x C-u) Incremental undo, separately remembered for each line. revert-line (M-r) Undo all changes made to this line. This is like executing the undo command enough times to return the line to its initial state. tilde-expand (M-&) Perform tilde expansion on the current word. set-mark (C-@, M-<space>) Set the mark to the point. If a numeric argument is supplied, the mark is set to that position. exchange-point-and-mark (C-x C-x) Swap the point with the mark. The current cursor position is set to the saved position, and the old cursor position is saved as the mark. character-search (C-]) A character is read and point is moved to the next occurrence of that character. A negative argument searches for previous occurrences. character-search-backward (M-C-]) A character is read and point is moved to the previous occurrence of that character. A negative argument searches for subsequent occurrences. skip-csi-sequence Read enough characters to consume a multi-key sequence such as those defined for keys like Home and End. Such sequences begin with a Control Sequence Indicator (CSI), usually ESC-[. If this sequence is bound to "\[", keys producing such sequences will have no effect unless explicitly bound to a readline command, instead of inserting stray characters into the editing buffer. This is unbound by default, but usually bound to ESC-[. insert-comment (M-#) Without a numeric argument, the value of the readline comment-begin variable is inserted at the beginning of the current line. If a numeric argument is supplied, this command acts as a toggle: if the characters at the beginning of the line do not match the value of comment-begin, the value is inserted, otherwise the characters in comment-begin are deleted from the beginning of the line. In either case, the line is accepted as if a newline had been typed. The default value of comment-begin causes this command to make the current line a shell comment. If a numeric argument causes the comment character to be removed, the line will be executed by the shell. spell-correct-word (C-x s) Perform spelling correction on the current word, treating it as a directory or filename, in the same way as the cdspell shell option. Word boundaries are the same as those used by shell-forward-word. glob-complete-word (M-g) The word before point is treated as a pattern for pathname expansion, with an asterisk implicitly appended. This pattern is used to generate a list of matching filenames for possible completions. glob-expand-word (C-x *) The word before point is treated as a pattern for pathname expansion, and the list of matching filenames is inserted, replacing the word. If a numeric argument is supplied, an asterisk is appended before pathname expansion. glob-list-expansions (C-x g) The list of expansions that would have been generated by glob-expand-word is displayed, and the line is redrawn. If a numeric argument is supplied, an asterisk is appended before pathname expansion. dump-functions Print all of the functions and their key bindings to the readline output stream. If a numeric argument is supplied, the output is formatted in such a way that it can be made part of an inputrc file. dump-variables Print all of the settable readline variables and their values to the readline output stream. If a numeric argument is supplied, the output is formatted in such a way that it can be made part of an inputrc file. dump-macros Print all of the readline key sequences bound to macros and the strings they output. If a numeric argument is supplied, the output is formatted in such a way that it can be made part of an inputrc file. display-shell-version (C-x C-v) Display version information about the current instance of bash. Programmable Completion When word completion is attempted for an argument to a command for which a completion specification (a compspec) has been defined using the complete builtin (see SHELL BUILTIN COMMANDS below), the programmable completion facilities are invoked. First, the command name is identified. If the command word is the empty string (completion attempted at the beginning of an empty line), any compspec defined with the -E option to complete is used. If a compspec has been defined for that command, the compspec is used to generate the list of possible completions for the word. If the command word is a full pathname, a compspec for the full pathname is searched for first. If no compspec is found for the full pathname, an attempt is made to find a compspec for the portion following the final slash. If those searches do not result in a compspec, any compspec defined with the -D option to complete is used as the default. If there is no default compspec, bash attempts alias expansion on the command word as a final resort, and attempts to find a compspec for the command word from any successful expansion. Once a compspec has been found, it is used to generate the list of matching words. If a compspec is not found, the default bash completion as described above under Completing is performed. First, the actions specified by the compspec are used. Only matches which are prefixed by the word being completed are returned. When the -f or -d option is used for filename or directory name completion, the shell variable FIGNORE is used to filter the matches. Any completions specified by a pathname expansion pattern to the -G option are generated next. The words generated by the pattern need not match the word being completed. The GLOBIGNORE shell variable is not used to filter the matches, but the FIGNORE variable is used. Next, the string specified as the argument to the -W option is considered. The string is first split using the characters in the IFS special variable as delimiters. Shell quoting is honored. Each word is then expanded using brace expansion, tilde expansion, parameter and variable expansion, command substitution, and arithmetic expansion, as described above under EXPANSION. The results are split using the rules described above under Word Splitting. The results of the expansion are prefix- matched against the word being completed, and the matching words become the possible completions. After these matches have been generated, any shell function or command specified with the -F and -C options is invoked. When the command or function is invoked, the COMP_LINE, COMP_POINT, COMP_KEY, and COMP_TYPE variables are assigned values as described above under Shell Variables. If a shell function is being invoked, the COMP_WORDS and COMP_CWORD variables are also set. When the function or command is invoked, the first argument ($1) is the name of the command whose arguments are being completed, the second argument ($2) is the word being completed, and the third argument ($3) is the word preceding the word being completed on the current command line. No filtering of the generated completions against the word being completed is performed; the function or command has complete freedom in generating the matches. Any function specified with -F is invoked first. The function may use any of the shell facilities, including the compgen builtin described below, to generate the matches. It must put the possible completions in the COMPREPLY array variable, one per array element. Next, any command specified with the -C option is invoked in an environment equivalent to command substitution. It should print a list of completions, one per line, to the standard output. Backslash may be used to escape a newline, if necessary. After all of the possible completions are generated, any filter specified with the -X option is applied to the list. The filter is a pattern as used for pathname expansion; a & in the pattern is replaced with the text of the word being completed. A literal & may be escaped with a backslash; the backslash is removed before attempting a match. Any completion that matches the pattern will be removed from the list. A leading ! negates the pattern; in this case any completion not matching the pattern will be removed. If the nocasematch shell option is enabled, the match is performed without regard to the case of alphabetic characters. Finally, any prefix and suffix specified with the -P and -S options are added to each member of the completion list, and the result is returned to the readline completion code as the list of possible completions. If the previously-applied actions do not generate any matches, and the -o dirnames option was supplied to complete when the compspec was defined, directory name completion is attempted. If the -o plusdirs option was supplied to complete when the compspec was defined, directory name completion is attempted and any matches are added to the results of the other actions. By default, if a compspec is found, whatever it generates is returned to the completion code as the full set of possible completions. The default bash completions are not attempted, and the readline default of filename completion is disabled. If the -o bashdefault option was supplied to complete when the compspec was defined, the bash default completions are attempted if the compspec generates no matches. If the -o default option was supplied to complete when the compspec was defined, readline's default completion will be performed if the compspec (and, if attempted, the default bash completions) generate no matches. When a compspec indicates that directory name completion is desired, the programmable completion functions force readline to append a slash to completed names which are symbolic links to directories, subject to the value of the mark-directories readline variable, regardless of the setting of the mark- symlinked-directories readline variable. There is some support for dynamically modifying completions. This is most useful when used in combination with a default completion specified with complete -D. It's possible for shell functions executed as completion handlers to indicate that completion should be retried by returning an exit status of 124. If a shell function returns 124, and changes the compspec associated with the command on which completion is being attempted (supplied as the first argument when the function is executed), programmable completion restarts from the beginning, with an attempt to find a new compspec for that command. This allows a set of completions to be built dynamically as completion is attempted, rather than being loaded all at once. For instance, assuming that there is a library of compspecs, each kept in a file corresponding to the name of the command, the following default completion function would load completions dynamically: _completion_loader() { . "/etc/bash_completion.d/$1.sh" >/dev/null 2>&1 && return 124 } complete -D -F _completion_loader -o bashdefault -o default HISTORY top When the -o history option to the set builtin is enabled, the shell provides access to the command history, the list of commands previously typed. The value of the HISTSIZE variable is used as the number of commands to save in a history list. The text of the last HISTSIZE commands (default 500) is saved. The shell stores each command in the history list prior to parameter and variable expansion (see EXPANSION above) but after history expansion is performed, subject to the values of the shell variables HISTIGNORE and HISTCONTROL. On startup, the history is initialized from the file named by the variable HISTFILE (default ~/.bash_history). The file named by the value of HISTFILE is truncated, if necessary, to contain no more than the number of lines specified by the value of HISTFILESIZE. If HISTFILESIZE is unset, or set to null, a non- numeric value, or a numeric value less than zero, the history file is not truncated. When the history file is read, lines beginning with the history comment character followed immediately by a digit are interpreted as timestamps for the following history line. These timestamps are optionally displayed depending on the value of the HISTTIMEFORMAT variable. When a shell with history enabled exits, the last $HISTSIZE lines are copied from the history list to $HISTFILE. If the histappend shell option is enabled (see the description of shopt under SHELL BUILTIN COMMANDS below), the lines are appended to the history file, otherwise the history file is overwritten. If HISTFILE is unset, or if the history file is unwritable, the history is not saved. If the HISTTIMEFORMAT variable is set, time stamps are written to the history file, marked with the history comment character, so they may be preserved across shell sessions. This uses the history comment character to distinguish timestamps from other history lines. After saving the history, the history file is truncated to contain no more than HISTFILESIZE lines. If HISTFILESIZE is unset, or set to null, a non-numeric value, or a numeric value less than zero, the history file is not truncated. The builtin command fc (see SHELL BUILTIN COMMANDS below) may be used to list or edit and re-execute a portion of the history list. The history builtin may be used to display or modify the history list and manipulate the history file. When using command-line editing, search commands are available in each editing mode that provide access to the history list. The shell allows control over which commands are saved on the history list. The HISTCONTROL and HISTIGNORE variables may be set to cause the shell to save only a subset of the commands entered. The cmdhist shell option, if enabled, causes the shell to attempt to save each line of a multi-line command in the same history entry, adding semicolons where necessary to preserve syntactic correctness. The lithist shell option causes the shell to save the command with embedded newlines instead of semicolons. See the description of the shopt builtin below under SHELL BUILTIN COMMANDS for information on setting and unsetting shell options. HISTORY EXPANSION top The shell supports a history expansion feature that is similar to the history expansion in csh. This section describes what syntax features are available. This feature is enabled by default for interactive shells, and can be disabled using the +H option to the set builtin command (see SHELL BUILTIN COMMANDS below). Non- interactive shells do not perform history expansion by default. History expansions introduce words from the history list into the input stream, making it easy to repeat commands, insert the arguments to a previous command into the current input line, or fix errors in previous commands quickly. History expansion is performed immediately after a complete line is read, before the shell breaks it into words, and is performed on each line individually without taking quoting on previous lines into account. It takes place in two parts. The first is to determine which line from the history list to use during substitution. The second is to select portions of that line for inclusion into the current one. The line selected from the history is the event, and the portions of that line that are acted upon are words. Various modifiers are available to manipulate the selected words. The line is broken into words in the same fashion as when reading input, so that several metacharacter-separated words surrounded by quotes are considered one word. History expansions are introduced by the appearance of the history expansion character, which is ! by default. Only backslash (\) and single quotes can quote the history expansion character, but the history expansion character is also treated as quoted if it immediately precedes the closing double quote in a double-quoted string. Several characters inhibit history expansion if found immediately following the history expansion character, even if it is unquoted: space, tab, newline, carriage return, and =. If the extglob shell option is enabled, ( will also inhibit expansion. Several shell options settable with the shopt builtin may be used to tailor the behavior of history expansion. If the histverify shell option is enabled (see the description of the shopt builtin below), and readline is being used, history substitutions are not immediately passed to the shell parser. Instead, the expanded line is reloaded into the readline editing buffer for further modification. If readline is being used, and the histreedit shell option is enabled, a failed history substitution will be reloaded into the readline editing buffer for correction. The -p option to the history builtin command may be used to see what a history expansion will do before using it. The -s option to the history builtin may be used to add commands to the end of the history list without actually executing them, so that they are available for subsequent recall. The shell allows control of the various characters used by the history expansion mechanism (see the description of histchars above under Shell Variables). The shell uses the history comment character to mark history timestamps when writing the history file. Event Designators An event designator is a reference to a command line entry in the history list. Unless the reference is absolute, events are relative to the current position in the history list. ! Start a history substitution, except when followed by a blank, newline, carriage return, = or ( (when the extglob shell option is enabled using the shopt builtin). !n Refer to command line n. !-n Refer to the current command minus n. !! Refer to the previous command. This is a synonym for `!-1'. !string Refer to the most recent command preceding the current position in the history list starting with string. !?string[?] Refer to the most recent command preceding the current position in the history list containing string. The trailing ? may be omitted if string is followed immediately by a newline. If string is missing, the string from the most recent search is used; it is an error if there is no previous search string. ^string1^string2^ Quick substitution. Repeat the previous command, replacing string1 with string2. Equivalent to ``!!:s^string1^string2^'' (see Modifiers below). !# The entire command line typed so far. Word Designators Word designators are used to select desired words from the event. A : separates the event specification from the word designator. It may be omitted if the word designator begins with a ^, $, *, -, or %. Words are numbered from the beginning of the line, with the first word being denoted by 0 (zero). Words are inserted into the current line separated by single spaces. 0 (zero) The zeroth word. For the shell, this is the command word. n The nth word. ^ The first argument. That is, word 1. $ The last word. This is usually the last argument, but will expand to the zeroth word if there is only one word in the line. % The first word matched by the most recent `?string?' search, if the search string begins with a character that is part of a word. x-y A range of words; `-y' abbreviates `0-y'. * All of the words but the zeroth. This is a synonym for `1-$'. It is not an error to use * if there is just one word in the event; the empty string is returned in that case. x* Abbreviates x-$. x- Abbreviates x-$ like x*, but omits the last word. If x is missing, it defaults to 0. If a word designator is supplied without an event specification, the previous command is used as the event. Modifiers After the optional word designator, there may appear a sequence of one or more of the following modifiers, each preceded by a `:'. These modify, or edit, the word or words selected from the history event. h Remove a trailing filename component, leaving only the head. t Remove all leading filename components, leaving the tail. r Remove a trailing suffix of the form .xxx, leaving the basename. e Remove all but the trailing suffix. p Print the new command but do not execute it. q Quote the substituted words, escaping further substitutions. x Quote the substituted words as with q, but break into words at blanks and newlines. The q and x modifiers are mutually exclusive; the last one supplied is used. s/old/new/ Substitute new for the first occurrence of old in the event line. Any character may be used as the delimiter in place of /. The final delimiter is optional if it is the last character of the event line. The delimiter may be quoted in old and new with a single backslash. If & appears in new, it is replaced by old. A single backslash will quote the &. If old is null, it is set to the last old substituted, or, if no previous history substitutions took place, the last string in a !?string[?] search. If new is null, each matching old is deleted. & Repeat the previous substitution. g Cause changes to be applied over the entire event line. This is used in conjunction with `:s' (e.g., `:gs/old/new/') or `:&'. If used with `:s', any delimiter can be used in place of /, and the final delimiter is optional if it is the last character of the event line. An a may be used as a synonym for g. G Apply the following `s' or `&' modifier once to each word in the event line. SHELL BUILTIN COMMANDS top Unless otherwise noted, each builtin command documented in this section as accepting options preceded by - accepts -- to signify the end of the options. The :, true, false, and test/[ builtins do not accept options and do not treat -- specially. The exit, logout, return, break, continue, let, and shift builtins accept and process arguments beginning with - without requiring --. Other builtins that accept arguments but are not specified as accepting options interpret arguments beginning with - as invalid options and require -- to prevent this interpretation. : [arguments] No effect; the command does nothing beyond expanding arguments and performing any specified redirections. The return status is zero. . filename [arguments] source filename [arguments] Read and execute commands from filename in the current shell environment and return the exit status of the last command executed from filename. If filename does not contain a slash, filenames in PATH are used to find the directory containing filename, but filename does not need to be executable. The file searched for in PATH need not be executable. When bash is not in posix mode, it searches the current directory if no file is found in PATH. If the sourcepath option to the shopt builtin command is turned off, the PATH is not searched. If any arguments are supplied, they become the positional parameters when filename is executed. Otherwise the positional parameters are unchanged. If the -T option is enabled, . inherits any trap on DEBUG; if it is not, any DEBUG trap string is saved and restored around the call to ., and . unsets the DEBUG trap while it executes. If -T is not set, and the sourced file changes the DEBUG trap, the new value is retained when . completes. The return status is the status of the last command exited within the script (0 if no commands are executed), and false if filename is not found or cannot be read. alias [-p] [name[=value] ...] Alias with no arguments or with the -p option prints the list of aliases in the form alias name=value on standard output. When arguments are supplied, an alias is defined for each name whose value is given. A trailing space in value causes the next word to be checked for alias substitution when the alias is expanded. For each name in the argument list for which no value is supplied, the name and value of the alias is printed. Alias returns true unless a name is given for which no alias has been defined. bg [jobspec ...] Resume each suspended job jobspec in the background, as if it had been started with &. If jobspec is not present, the shell's notion of the current job is used. bg jobspec returns 0 unless run when job control is disabled or, when run with job control enabled, any specified jobspec was not found or was started without job control. bind [-m keymap] [-lpsvPSVX] bind [-m keymap] [-q function] [-u function] [-r keyseq] bind [-m keymap] -f filename bind [-m keymap] -x keyseq:shell-command bind [-m keymap] keyseq:function-name bind [-m keymap] keyseq:readline-command bind readline-command-line Display current readline key and function bindings, bind a key sequence to a readline function or macro, or set a readline variable. Each non-option argument is a command as it would appear in a readline initialization file such as .inputrc, but each binding or command must be passed as a separate argument; e.g., '"\C-x\C-r": re-read-init-file'. Options, if supplied, have the following meanings: -m keymap Use keymap as the keymap to be affected by the subsequent bindings. Acceptable keymap names are emacs, emacs-standard, emacs-meta, emacs-ctlx, vi, vi-move, vi-command, and vi-insert. vi is equivalent to vi-command (vi-move is also a synonym); emacs is equivalent to emacs-standard. -l List the names of all readline functions. -p Display readline function names and bindings in such a way that they can be re-read. -P List current readline function names and bindings. -s Display readline key sequences bound to macros and the strings they output in such a way that they can be re-read. -S Display readline key sequences bound to macros and the strings they output. -v Display readline variable names and values in such a way that they can be re-read. -V List current readline variable names and values. -f filename Read key bindings from filename. -q function Query about which keys invoke the named function. -u function Unbind all keys bound to the named function. -r keyseq Remove any current binding for keyseq. -x keyseq:shell-command Cause shell-command to be executed whenever keyseq is entered. When shell-command is executed, the shell sets the READLINE_LINE variable to the contents of the readline line buffer and the READLINE_POINT and READLINE_MARK variables to the current location of the insertion point and the saved insertion point (the mark), respectively. The shell assigns any numeric argument the user supplied to the READLINE_ARGUMENT variable. If there was no argument, that variable is not set. If the executed command changes the value of any of READLINE_LINE, READLINE_POINT, or READLINE_MARK, those new values will be reflected in the editing state. -X List all key sequences bound to shell commands and the associated commands in a format that can be reused as input. The return value is 0 unless an unrecognized option is given or an error occurred. break [n] Exit from within a for, while, until, or select loop. If n is specified, break n levels. n must be 1. If n is greater than the number of enclosing loops, all enclosing loops are exited. The return value is 0 unless n is not greater than or equal to 1. builtin shell-builtin [arguments] Execute the specified shell builtin, passing it arguments, and return its exit status. This is useful when defining a function whose name is the same as a shell builtin, retaining the functionality of the builtin within the function. The cd builtin is commonly redefined this way. The return status is false if shell-builtin is not a shell builtin command. caller [expr] Returns the context of any active subroutine call (a shell function or a script executed with the . or source builtins). Without expr, caller displays the line number and source filename of the current subroutine call. If a non-negative integer is supplied as expr, caller displays the line number, subroutine name, and source file corresponding to that position in the current execution call stack. This extra information may be used, for example, to print a stack trace. The current frame is frame 0. The return value is 0 unless the shell is not executing a subroutine call or expr does not correspond to a valid position in the call stack. cd [-L|[-P [-e]] [-@]] [dir] Change the current directory to dir. if dir is not supplied, the value of the HOME shell variable is the default. The variable CDPATH defines the search path for the directory containing dir: each directory name in CDPATH is searched for dir. Alternative directory names in CDPATH are separated by a colon (:). A null directory name in CDPATH is the same as the current directory, i.e., ``.''. If dir begins with a slash (/), then CDPATH is not used. The -P option causes cd to use the physical directory structure by resolving symbolic links while traversing dir and before processing instances of .. in dir (see also the -P option to the set builtin command); the -L option forces symbolic links to be followed by resolving the link after processing instances of .. in dir. If .. appears in dir, it is processed by removing the immediately previous pathname component from dir, back to a slash or the beginning of dir. If the -e option is supplied with -P, and the current working directory cannot be successfully determined after a successful directory change, cd will return an unsuccessful status. On systems that support it, the -@ option presents the extended attributes associated with a file as a directory. An argument of - is converted to $OLDPWD before the directory change is attempted. If a non-empty directory name from CDPATH is used, or if - is the first argument, and the directory change is successful, the absolute pathname of the new working directory is written to the standard output. If the directory change is successful, cd sets the value of the PWD environment variable to the new directory name, and sets the OLDPWD environment variable to the value of the current working directory before the change. The return value is true if the directory was successfully changed; false otherwise. command [-pVv] command [arg ...] Run command with args suppressing the normal shell function lookup. Only builtin commands or commands found in the PATH are executed. If the -p option is given, the search for command is performed using a default value for PATH that is guaranteed to find all of the standard utilities. If either the -V or -v option is supplied, a description of command is printed. The -v option causes a single word indicating the command or filename used to invoke command to be displayed; the -V option produces a more verbose description. If the -V or -v option is supplied, the exit status is 0 if command was found, and 1 if not. If neither option is supplied and an error occurred or command cannot be found, the exit status is 127. Otherwise, the exit status of the command builtin is the exit status of command. compgen [option] [word] Generate possible completion matches for word according to the options, which may be any option accepted by the complete builtin with the exception of -p and -r, and write the matches to the standard output. When using the -F or -C options, the various shell variables set by the programmable completion facilities, while available, will not have useful values. The matches will be generated in the same way as if the programmable completion code had generated them directly from a completion specification with the same flags. If word is specified, only those completions matching word will be displayed. The return value is true unless an invalid option is supplied, or no matches were generated. complete [-abcdefgjksuv] [-o comp-option] [-DEI] [-A action] [-G globpat] [-W wordlist] [-F function] [-C command] [-X filterpat] [-P prefix] [-S suffix] name [name ...] complete -pr [-DEI] [name ...] Specify how arguments to each name should be completed. If the -p option is supplied, or if no options are supplied, existing completion specifications are printed in a way that allows them to be reused as input. The -r option removes a completion specification for each name, or, if no names are supplied, all completion specifications. The -D option indicates that other supplied options and actions should apply to the ``default'' command completion; that is, completion attempted on a command for which no completion has previously been defined. The -E option indicates that other supplied options and actions should apply to ``empty'' command completion; that is, completion attempted on a blank line. The -I option indicates that other supplied options and actions should apply to completion on the initial non-assignment word on the line, or after a command delimiter such as ; or |, which is usually command name completion. If multiple options are supplied, the -D option takes precedence over -E, and both take precedence over -I. If any of -D, -E, or -I are supplied, any other name arguments are ignored; these completions only apply to the case specified by the option. The process of applying these completion specifications when word completion is attempted is described above under Programmable Completion. Other options, if specified, have the following meanings. The arguments to the -G, -W, and -X options (and, if necessary, the -P and -S options) should be quoted to protect them from expansion before the complete builtin is invoked. -o comp-option The comp-option controls several aspects of the compspec's behavior beyond the simple generation of completions. comp-option may be one of: bashdefault Perform the rest of the default bash completions if the compspec generates no matches. default Use readline's default filename completion if the compspec generates no matches. dirnames Perform directory name completion if the compspec generates no matches. filenames Tell readline that the compspec generates filenames, so it can perform any filename-specific processing (like adding a slash to directory names, quoting special characters, or suppressing trailing spaces). Intended to be used with shell functions. noquote Tell readline not to quote the completed words if they are filenames (quoting filenames is the default). nosort Tell readline not to sort the list of possible completions alphabetically. nospace Tell readline not to append a space (the default) to words completed at the end of the line. plusdirs After any matches defined by the compspec are generated, directory name completion is attempted and any matches are added to the results of the other actions. -A action The action may be one of the following to generate a list of possible completions: alias Alias names. May also be specified as -a. arrayvar Array variable names. binding Readline key binding names. builtin Names of shell builtin commands. May also be specified as -b. command Command names. May also be specified as -c. directory Directory names. May also be specified as -d. disabled Names of disabled shell builtins. enabled Names of enabled shell builtins. export Names of exported shell variables. May also be specified as -e. file File names. May also be specified as -f. function Names of shell functions. group Group names. May also be specified as -g. helptopic Help topics as accepted by the help builtin. hostname Hostnames, as taken from the file specified by the HOSTFILE shell variable. job Job names, if job control is active. May also be specified as -j. keyword Shell reserved words. May also be specified as -k. running Names of running jobs, if job control is active. service Service names. May also be specified as -s. setopt Valid arguments for the -o option to the set builtin. shopt Shell option names as accepted by the shopt builtin. signal Signal names. stopped Names of stopped jobs, if job control is active. user User names. May also be specified as -u. variable Names of all shell variables. May also be specified as -v. -C command command is executed in a subshell environment, and its output is used as the possible completions. Arguments are passed as with the -F option. -F function The shell function function is executed in the current shell environment. When the function is executed, the first argument ($1) is the name of the command whose arguments are being completed, the second argument ($2) is the word being completed, and the third argument ($3) is the word preceding the word being completed on the current command line. When it finishes, the possible completions are retrieved from the value of the COMPREPLY array variable. -G globpat The pathname expansion pattern globpat is expanded to generate the possible completions. -P prefix prefix is added at the beginning of each possible completion after all other options have been applied. -S suffix suffix is appended to each possible completion after all other options have been applied. -W wordlist The wordlist is split using the characters in the IFS special variable as delimiters, and each resultant word is expanded. Shell quoting is honored within wordlist, in order to provide a mechanism for the words to contain shell metacharacters or characters in the value of IFS. The possible completions are the members of the resultant list which match the word being completed. -X filterpat filterpat is a pattern as used for pathname expansion. It is applied to the list of possible completions generated by the preceding options and arguments, and each completion matching filterpat is removed from the list. A leading ! in filterpat negates the pattern; in this case, any completion not matching filterpat is removed. The return value is true unless an invalid option is supplied, an option other than -p or -r is supplied without a name argument, an attempt is made to remove a completion specification for a name for which no specification exists, or an error occurs adding a completion specification. compopt [-o option] [-DEI] [+o option] [name] Modify completion options for each name according to the options, or for the currently-executing completion if no names are supplied. If no options are given, display the completion options for each name or the current completion. The possible values of option are those valid for the complete builtin described above. The -D option indicates that other supplied options should apply to the ``default'' command completion; that is, completion attempted on a command for which no completion has previously been defined. The -E option indicates that other supplied options should apply to ``empty'' command completion; that is, completion attempted on a blank line. The -I option indicates that other supplied options should apply to completion on the initial non-assignment word on the line, or after a command delimiter such as ; or |, which is usually command name completion. The return value is true unless an invalid option is supplied, an attempt is made to modify the options for a name for which no completion specification exists, or an output error occurs. continue [n] Resume the next iteration of the enclosing for, while, until, or select loop. If n is specified, resume at the nth enclosing loop. n must be 1. If n is greater than the number of enclosing loops, the last enclosing loop (the ``top-level'' loop) is resumed. The return value is 0 unless n is not greater than or equal to 1. declare [-aAfFgiIlnrtux] [-p] [name[=value] ...] typeset [-aAfFgiIlnrtux] [-p] [name[=value] ...] Declare variables and/or give them attributes. If no names are given then display the values of variables. The -p option will display the attributes and values of each name. When -p is used with name arguments, additional options, other than -f and -F, are ignored. When -p is supplied without name arguments, it will display the attributes and values of all variables having the attributes specified by the additional options. If no other options are supplied with -p, declare will display the attributes and values of all shell variables. The -f option will restrict the display to shell functions. The -F option inhibits the display of function definitions; only the function name and attributes are printed. If the extdebug shell option is enabled using shopt, the source file name and line number where each name is defined are displayed as well. The -F option implies -f. The -g option forces variables to be created or modified at the global scope, even when declare is executed in a shell function. It is ignored in all other cases. The -I option causes local variables to inherit the attributes (except the nameref attribute) and value of any existing variable with the same name at a surrounding scope. If there is no existing variable, the local variable is initially unset. The following options can be used to restrict output to variables with the specified attribute or to give variables attributes: -a Each name is an indexed array variable (see Arrays above). -A Each name is an associative array variable (see Arrays above). -f Use function names only. -i The variable is treated as an integer; arithmetic evaluation (see ARITHMETIC EVALUATION above) is performed when the variable is assigned a value. -l When the variable is assigned a value, all upper- case characters are converted to lower-case. The upper-case attribute is disabled. -n Give each name the nameref attribute, making it a name reference to another variable. That other variable is defined by the value of name. All references, assignments, and attribute modifications to name, except those using or changing the -n attribute itself, are performed on the variable referenced by name's value. The nameref attribute cannot be applied to array variables. -r Make names readonly. These names cannot then be assigned values by subsequent assignment statements or unset. -t Give each name the trace attribute. Traced functions inherit the DEBUG and RETURN traps from the calling shell. The trace attribute has no special meaning for variables. -u When the variable is assigned a value, all lower- case characters are converted to upper-case. The lower-case attribute is disabled. -x Mark names for export to subsequent commands via the environment. Using `+' instead of `-' turns off the attribute instead, with the exceptions that +a and +A may not be used to destroy array variables and +r will not remove the readonly attribute. When used in a function, declare and typeset make each name local, as with the local command, unless the -g option is supplied. If a variable name is followed by =value, the value of the variable is set to value. When using -a or -A and the compound assignment syntax to create array variables, additional attributes do not take effect until subsequent assignments. The return value is 0 unless an invalid option is encountered, an attempt is made to define a function using ``-f foo=bar'', an attempt is made to assign a value to a readonly variable, an attempt is made to assign a value to an array variable without using the compound assignment syntax (see Arrays above), one of the names is not a valid shell variable name, an attempt is made to turn off readonly status for a readonly variable, an attempt is made to turn off array status for an array variable, or an attempt is made to display a non-existent function with -f. dirs [-clpv] [+n] [-n] Without options, displays the list of currently remembered directories. The default display is on a single line with directory names separated by spaces. Directories are added to the list with the pushd command; the popd command removes entries from the list. The current directory is always the first directory in the stack. -c Clears the directory stack by deleting all of the entries. -l Produces a listing using full pathnames; the default listing format uses a tilde to denote the home directory. -p Print the directory stack with one entry per line. -v Print the directory stack with one entry per line, prefixing each entry with its index in the stack. +n Displays the nth entry counting from the left of the list shown by dirs when invoked without options, starting with zero. -n Displays the nth entry counting from the right of the list shown by dirs when invoked without options, starting with zero. The return value is 0 unless an invalid option is supplied or n indexes beyond the end of the directory stack. disown [-ar] [-h] [jobspec ... | pid ... ] Without options, remove each jobspec from the table of active jobs. If jobspec is not present, and neither the -a nor the -r option is supplied, the current job is used. If the -h option is given, each jobspec is not removed from the table, but is marked so that SIGHUP is not sent to the job if the shell receives a SIGHUP. If no jobspec is supplied, the -a option means to remove or mark all jobs; the -r option without a jobspec argument restricts operation to running jobs. The return value is 0 unless a jobspec does not specify a valid job. echo [-neE] [arg ...] Output the args, separated by spaces, followed by a newline. The return status is 0 unless a write error occurs. If -n is specified, the trailing newline is suppressed. If the -e option is given, interpretation of the following backslash-escaped characters is enabled. The -E option disables the interpretation of these escape characters, even on systems where they are interpreted by default. The xpg_echo shell option may be used to dynamically determine whether or not echo expands these escape characters by default. echo does not interpret -- to mean the end of options. echo interprets the following escape sequences: \a alert (bell) \b backspace \c suppress further output \e \E an escape character \f form feed \n new line \r carriage return \t horizontal tab \v vertical tab \\ backslash \0nnn the eight-bit character whose value is the octal value nnn (zero to three octal digits) \xHH the eight-bit character whose value is the hexadecimal value HH (one or two hex digits) \uHHHH the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value HHHH (one to four hex digits) \UHHHHHHHH the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value HHHHHHHH (one to eight hex digits) enable [-a] [-dnps] [-f filename] [name ...] Enable and disable builtin shell commands. Disabling a builtin allows a disk command which has the same name as a shell builtin to be executed without specifying a full pathname, even though the shell normally searches for builtins before disk commands. If -n is used, each name is disabled; otherwise, names are enabled. For example, to use the test binary found via the PATH instead of the shell builtin version, run ``enable -n test''. The -f option means to load the new builtin command name from shared object filename, on systems that support dynamic loading. Bash will use the value of the BASH_LOADABLES_PATH variable as a colon-separated list of directories in which to search for filename. The default is system-dependent. The -d option will delete a builtin previously loaded with -f. If no name arguments are given, or if the -p option is supplied, a list of shell builtins is printed. With no other option arguments, the list consists of all enabled shell builtins. If -n is supplied, only disabled builtins are printed. If -a is supplied, the list printed includes all builtins, with an indication of whether or not each is enabled. If -s is supplied, the output is restricted to the POSIX special builtins. If no options are supplied and a name is not a shell builtin, enable will attempt to load name from a shared object named name, as if the command were ``enable -f name name . The return value is 0 unless a name is not a shell builtin or there is an error loading a new builtin from a shared object. eval [arg ...] The args are read and concatenated together into a single command. This command is then read and executed by the shell, and its exit status is returned as the value of eval. If there are no args, or only null arguments, eval returns 0. exec [-cl] [-a name] [command [arguments]] If command is specified, it replaces the shell. No new process is created. The arguments become the arguments to command. If the -l option is supplied, the shell places a dash at the beginning of the zeroth argument passed to command. This is what login(1) does. The -c option causes command to be executed with an empty environment. If -a is supplied, the shell passes name as the zeroth argument to the executed command. If command cannot be executed for some reason, a non-interactive shell exits, unless the execfail shell option is enabled. In that case, it returns failure. An interactive shell returns failure if the file cannot be executed. A subshell exits unconditionally if exec fails. If command is not specified, any redirections take effect in the current shell, and the return status is 0. If there is a redirection error, the return status is 1. exit [n] Cause the shell to exit with a status of n. If n is omitted, the exit status is that of the last command executed. A trap on EXIT is executed before the shell terminates. export [-fn] [name[=word]] ... export -p The supplied names are marked for automatic export to the environment of subsequently executed commands. If the -f option is given, the names refer to functions. If no names are given, or if the -p option is supplied, a list of names of all exported variables is printed. The -n option causes the export property to be removed from each name. If a variable name is followed by =word, the value of the variable is set to word. export returns an exit status of 0 unless an invalid option is encountered, one of the names is not a valid shell variable name, or -f is supplied with a name that is not a function. fc [-e ename] [-lnr] [first] [last] fc -s [pat=rep] [cmd] The first form selects a range of commands from first to last from the history list and displays or edits and re- executes them. First and last may be specified as a string (to locate the last command beginning with that string) or as a number (an index into the history list, where a negative number is used as an offset from the current command number). When listing, a first or last of 0 is equivalent to -1 and -0 is equivalent to the current command (usually the fc command); otherwise 0 is equivalent to -1 and -0 is invalid. If last is not specified, it is set to the current command for listing (so that ``fc -l -10'' prints the last 10 commands) and to first otherwise. If first is not specified, it is set to the previous command for editing and -16 for listing. The -n option suppresses the command numbers when listing. The -r option reverses the order of the commands. If the -l option is given, the commands are listed on standard output. Otherwise, the editor given by ename is invoked on a file containing those commands. If ename is not given, the value of the FCEDIT variable is used, and the value of EDITOR if FCEDIT is not set. If neither variable is set, vi is used. When editing is complete, the edited commands are echoed and executed. In the second form, command is re-executed after each instance of pat is replaced by rep. Command is interpreted the same as first above. A useful alias to use with this is ``r="fc -s"'', so that typing ``r cc'' runs the last command beginning with ``cc'' and typing ``r'' re-executes the last command. If the first form is used, the return value is 0 unless an invalid option is encountered or first or last specify history lines out of range. If the -e option is supplied, the return value is the value of the last command executed or failure if an error occurs with the temporary file of commands. If the second form is used, the return status is that of the command re-executed, unless cmd does not specify a valid history line, in which case fc returns failure. fg [jobspec] Resume jobspec in the foreground, and make it the current job. If jobspec is not present, the shell's notion of the current job is used. The return value is that of the command placed into the foreground, or failure if run when job control is disabled or, when run with job control enabled, if jobspec does not specify a valid job or jobspec specifies a job that was started without job control. getopts optstring name [arg ...] getopts is used by shell procedures to parse positional parameters. optstring contains the option characters to be recognized; if a character is followed by a colon, the option is expected to have an argument, which should be separated from it by white space. The colon and question mark characters may not be used as option characters. Each time it is invoked, getopts places the next option in the shell variable name, initializing name if it does not exist, and the index of the next argument to be processed into the variable OPTIND. OPTIND is initialized to 1 each time the shell or a shell script is invoked. When an option requires an argument, getopts places that argument into the variable OPTARG. The shell does not reset OPTIND automatically; it must be manually reset between multiple calls to getopts within the same shell invocation if a new set of parameters is to be used. When the end of options is encountered, getopts exits with a return value greater than zero. OPTIND is set to the index of the first non-option argument, and name is set to ?. getopts normally parses the positional parameters, but if more arguments are supplied as arg values, getopts parses those instead. getopts can report errors in two ways. If the first character of optstring is a colon, silent error reporting is used. In normal operation, diagnostic messages are printed when invalid options or missing option arguments are encountered. If the variable OPTERR is set to 0, no error messages will be displayed, even if the first character of optstring is not a colon. If an invalid option is seen, getopts places ? into name and, if not silent, prints an error message and unsets OPTARG. If getopts is silent, the option character found is placed in OPTARG and no diagnostic message is printed. If a required argument is not found, and getopts is not silent, a question mark (?) is placed in name, OPTARG is unset, and a diagnostic message is printed. If getopts is silent, then a colon (:) is placed in name and OPTARG is set to the option character found. getopts returns true if an option, specified or unspecified, is found. It returns false if the end of options is encountered or an error occurs. hash [-lr] [-p filename] [-dt] [name] Each time hash is invoked, the full pathname of the command name is determined by searching the directories in $PATH and remembered. Any previously-remembered pathname is discarded. If the -p option is supplied, no path search is performed, and filename is used as the full filename of the command. The -r option causes the shell to forget all remembered locations. The -d option causes the shell to forget the remembered location of each name. If the -t option is supplied, the full pathname to which each name corresponds is printed. If multiple name arguments are supplied with -t, the name is printed before the hashed full pathname. The -l option causes output to be displayed in a format that may be reused as input. If no arguments are given, or if only -l is supplied, information about remembered commands is printed. The return status is true unless a name is not found or an invalid option is supplied. help [-dms] [pattern] Display helpful information about builtin commands. If pattern is specified, help gives detailed help on all commands matching pattern; otherwise help for all the builtins and shell control structures is printed. -d Display a short description of each pattern -m Display the description of each pattern in a manpage-like format -s Display only a short usage synopsis for each pattern The return status is 0 unless no command matches pattern. history [n] history -c history -d offset history -d start-end history -anrw [filename] history -p arg [arg ...] history -s arg [arg ...] With no options, display the command history list with line numbers. Lines listed with a * have been modified. An argument of n lists only the last n lines. If the shell variable HISTTIMEFORMAT is set and not null, it is used as a format string for strftime(3) to display the time stamp associated with each displayed history entry. No intervening blank is printed between the formatted time stamp and the history line. If filename is supplied, it is used as the name of the history file; if not, the value of HISTFILE is used. Options, if supplied, have the following meanings: -c Clear the history list by deleting all the entries. -d offset Delete the history entry at position offset. If offset is negative, it is interpreted as relative to one greater than the last history position, so negative indices count back from the end of the history, and an index of -1 refers to the current history -d command. -d start-end Delete the range of history entries between positions start and end, inclusive. Positive and negative values for start and end are interpreted as described above. -a Append the ``new'' history lines to the history file. These are history lines entered since the beginning of the current bash session, but not already appended to the history file. -n Read the history lines not already read from the history file into the current history list. These are lines appended to the history file since the beginning of the current bash session. -r Read the contents of the history file and append them to the current history list. -w Write the current history list to the history file, overwriting the history file's contents. -p Perform history substitution on the following args and display the result on the standard output. Does not store the results in the history list. Each arg must be quoted to disable normal history expansion. -s Store the args in the history list as a single entry. The last command in the history list is removed before the args are added. If the HISTTIMEFORMAT variable is set, the time stamp information associated with each history entry is written to the history file, marked with the history comment character. When the history file is read, lines beginning with the history comment character followed immediately by a digit are interpreted as timestamps for the following history entry. The return value is 0 unless an invalid option is encountered, an error occurs while reading or writing the history file, an invalid offset or range is supplied as an argument to -d, or the history expansion supplied as an argument to -p fails. jobs [-lnprs] [ jobspec ... ] jobs -x command [ args ... ] The first form lists the active jobs. The options have the following meanings: -l List process IDs in addition to the normal information. -n Display information only about jobs that have changed status since the user was last notified of their status. -p List only the process ID of the job's process group leader. -r Display only running jobs. -s Display only stopped jobs. If jobspec is given, output is restricted to information about that job. The return status is 0 unless an invalid option is encountered or an invalid jobspec is supplied. If the -x option is supplied, jobs replaces any jobspec found in command or args with the corresponding process group ID, and executes command passing it args, returning its exit status. kill [-s sigspec | -n signum | -sigspec] [pid | jobspec] ... kill -l|-L [sigspec | exit_status] Send the signal named by sigspec or signum to the processes named by pid or jobspec. sigspec is either a case-insensitive signal name such as SIGKILL (with or without the SIG prefix) or a signal number; signum is a signal number. If sigspec is not present, then SIGTERM is assumed. An argument of -l lists the signal names. If any arguments are supplied when -l is given, the names of the signals corresponding to the arguments are listed, and the return status is 0. The exit_status argument to -l is a number specifying either a signal number or the exit status of a process terminated by a signal. The -L option is equivalent to -l. kill returns true if at least one signal was successfully sent, or false if an error occurs or an invalid option is encountered. let arg [arg ...] Each arg is an arithmetic expression to be evaluated (see ARITHMETIC EVALUATION above). If the last arg evaluates to 0, let returns 1; 0 is returned otherwise. local [option] [name[=value] ... | - ] For each argument, a local variable named name is created, and assigned value. The option can be any of the options accepted by declare. When local is used within a function, it causes the variable name to have a visible scope restricted to that function and its children. If name is -, the set of shell options is made local to the function in which local is invoked: shell options changed using the set builtin inside the function are restored to their original values when the function returns. The restore is effected as if a series of set commands were executed to restore the values that were in place before the function. With no operands, local writes a list of local variables to the standard output. It is an error to use local when not within a function. The return status is 0 unless local is used outside a function, an invalid name is supplied, or name is a readonly variable. logout Exit a login shell. mapfile [-d delim] [-n count] [-O origin] [-s count] [-t] [-u fd] [-C callback] [-c quantum] [array] readarray [-d delim] [-n count] [-O origin] [-s count] [-t] [-u fd] [-C callback] [-c quantum] [array] Read lines from the standard input into the indexed array variable array, or from file descriptor fd if the -u option is supplied. The variable MAPFILE is the default array. Options, if supplied, have the following meanings: -d The first character of delim is used to terminate each input line, rather than newline. If delim is the empty string, mapfile will terminate a line when it reads a NUL character. -n Copy at most count lines. If count is 0, all lines are copied. -O Begin assigning to array at index origin. The default index is 0. -s Discard the first count lines read. -t Remove a trailing delim (default newline) from each line read. -u Read lines from file descriptor fd instead of the standard input. -C Evaluate callback each time quantum lines are read. The -c option specifies quantum. -c Specify the number of lines read between each call to callback. If -C is specified without -c, the default quantum is 5000. When callback is evaluated, it is supplied the index of the next array element to be assigned and the line to be assigned to that element as additional arguments. callback is evaluated after the line is read but before the array element is assigned. If not supplied with an explicit origin, mapfile will clear array before assigning to it. mapfile returns successfully unless an invalid option or option argument is supplied, array is invalid or unassignable, or if array is not an indexed array. popd [-n] [+n] [-n] Removes entries from the directory stack. The elements are numbered from 0 starting at the first directory listed by dirs. With no arguments, popd removes the top directory from the stack, and changes to the new top directory. Arguments, if supplied, have the following meanings: -n Suppresses the normal change of directory when removing directories from the stack, so that only the stack is manipulated. +n Removes the nth entry counting from the left of the list shown by dirs, starting with zero, from the stack. For example: ``popd +0'' removes the first directory, ``popd +1'' the second. -n Removes the nth entry counting from the right of the list shown by dirs, starting with zero. For example: ``popd -0'' removes the last directory, ``popd -1'' the next to last. If the top element of the directory stack is modified, and the -n option was not supplied, popd uses the cd builtin to change to the directory at the top of the stack. If the cd fails, popd returns a non-zero value. Otherwise, popd returns false if an invalid option is encountered, the directory stack is empty, or a non- existent directory stack entry is specified. If the popd command is successful, bash runs dirs to show the final contents of the directory stack, and the return status is 0. printf [-v var] format [arguments] Write the formatted arguments to the standard output under the control of the format. The -v option causes the output to be assigned to the variable var rather than being printed to the standard output. The format is a character string which contains three types of objects: plain characters, which are simply copied to standard output, character escape sequences, which are converted and copied to the standard output, and format specifications, each of which causes printing of the next successive argument. In addition to the standard printf(1) format specifications, printf interprets the following extensions: %b causes printf to expand backslash escape sequences in the corresponding argument in the same way as echo -e. %q causes printf to output the corresponding argument in a format that can be reused as shell input. %Q like %q, but applies any supplied precision to the argument before quoting it. %(datefmt)T causes printf to output the date-time string resulting from using datefmt as a format string for strftime(3). The corresponding argument is an integer representing the number of seconds since the epoch. Two special argument values may be used: -1 represents the current time, and -2 represents the time the shell was invoked. If no argument is specified, conversion behaves as if -1 had been given. This is an exception to the usual printf behavior. The %b, %q, and %T directives all use the field width and precision arguments from the format specification and write that many bytes from (or use that wide a field for) the expanded argument, which usually contains more characters than the original. Arguments to non-string format specifiers are treated as C constants, except that a leading plus or minus sign is allowed, and if the leading character is a single or double quote, the value is the ASCII value of the following character. The format is reused as necessary to consume all of the arguments. If the format requires more arguments than are supplied, the extra format specifications behave as if a zero value or null string, as appropriate, had been supplied. The return value is zero on success, non-zero on failure. pushd [-n] [+n] [-n] pushd [-n] [dir] Adds a directory to the top of the directory stack, or rotates the stack, making the new top of the stack the current working directory. With no arguments, pushd exchanges the top two elements of the directory stack. Arguments, if supplied, have the following meanings: -n Suppresses the normal change of directory when rotating or adding directories to the stack, so that only the stack is manipulated. +n Rotates the stack so that the nth directory (counting from the left of the list shown by dirs, starting with zero) is at the top. -n Rotates the stack so that the nth directory (counting from the right of the list shown by dirs, starting with zero) is at the top. dir Adds dir to the directory stack at the top After the stack has been modified, if the -n option was not supplied, pushd uses the cd builtin to change to the directory at the top of the stack. If the cd fails, pushd returns a non-zero value. Otherwise, if no arguments are supplied, pushd returns 0 unless the directory stack is empty. When rotating the directory stack, pushd returns 0 unless the directory stack is empty or a non-existent directory stack element is specified. If the pushd command is successful, bash runs dirs to show the final contents of the directory stack. pwd [-LP] Print the absolute pathname of the current working directory. The pathname printed contains no symbolic links if the -P option is supplied or the -o physical option to the set builtin command is enabled. If the -L option is used, the pathname printed may contain symbolic links. The return status is 0 unless an error occurs while reading the name of the current directory or an invalid option is supplied. read [-ers] [-a aname] [-d delim] [-i text] [-n nchars] [-N nchars] [-p prompt] [-t timeout] [-u fd] [name ...] One line is read from the standard input, or from the file descriptor fd supplied as an argument to the -u option, split into words as described above under Word Splitting, and the first word is assigned to the first name, the second word to the second name, and so on. If there are more words than names, the remaining words and their intervening delimiters are assigned to the last name. If there are fewer words read from the input stream than names, the remaining names are assigned empty values. The characters in IFS are used to split the line into words using the same rules the shell uses for expansion (described above under Word Splitting). The backslash character (\) may be used to remove any special meaning for the next character read and for line continuation. Options, if supplied, have the following meanings: -a aname The words are assigned to sequential indices of the array variable aname, starting at 0. aname is unset before any new values are assigned. Other name arguments are ignored. -d delim The first character of delim is used to terminate the input line, rather than newline. If delim is the empty string, read will terminate a line when it reads a NUL character. -e If the standard input is coming from a terminal, readline (see READLINE above) is used to obtain the line. Readline uses the current (or default, if line editing was not previously active) editing settings, but uses readline's default filename completion. -i text If readline is being used to read the line, text is placed into the editing buffer before editing begins. -n nchars read returns after reading nchars characters rather than waiting for a complete line of input, but honors a delimiter if fewer than nchars characters are read before the delimiter. -N nchars read returns after reading exactly nchars characters rather than waiting for a complete line of input, unless EOF is encountered or read times out. Delimiter characters encountered in the input are not treated specially and do not cause read to return until nchars characters are read. The result is not split on the characters in IFS; the intent is that the variable is assigned exactly the characters read (with the exception of backslash; see the -r option below). -p prompt Display prompt on standard error, without a trailing newline, before attempting to read any input. The prompt is displayed only if input is coming from a terminal. -r Backslash does not act as an escape character. The backslash is considered to be part of the line. In particular, a backslash-newline pair may not then be used as a line continuation. -s Silent mode. If input is coming from a terminal, characters are not echoed. -t timeout Cause read to time out and return failure if a complete line of input (or a specified number of characters) is not read within timeout seconds. timeout may be a decimal number with a fractional portion following the decimal point. This option is only effective if read is reading input from a terminal, pipe, or other special file; it has no effect when reading from regular files. If read times out, read saves any partial input read into the specified variable name. If timeout is 0, read returns immediately, without trying to read any data. The exit status is 0 if input is available on the specified file descriptor, or the read will return EOF, non-zero otherwise. The exit status is greater than 128 if the timeout is exceeded. -u fd Read input from file descriptor fd. If no names are supplied, the line read, without the ending delimiter but otherwise unmodified, is assigned to the variable REPLY. The exit status is zero, unless end- of-file is encountered, read times out (in which case the status is greater than 128), a variable assignment error (such as assigning to a readonly variable) occurs, or an invalid file descriptor is supplied as the argument to -u. readonly [-aAf] [-p] [name[=word] ...] The given names are marked readonly; the values of these names may not be changed by subsequent assignment. If the -f option is supplied, the functions corresponding to the names are so marked. The -a option restricts the variables to indexed arrays; the -A option restricts the variables to associative arrays. If both options are supplied, -A takes precedence. If no name arguments are given, or if the -p option is supplied, a list of all readonly names is printed. The other options may be used to restrict the output to a subset of the set of readonly names. The -p option causes output to be displayed in a format that may be reused as input. If a variable name is followed by =word, the value of the variable is set to word. The return status is 0 unless an invalid option is encountered, one of the names is not a valid shell variable name, or -f is supplied with a name that is not a function. return [n] Causes a function to stop executing and return the value specified by n to its caller. If n is omitted, the return status is that of the last command executed in the function body. If return is executed by a trap handler, the last command used to determine the status is the last command executed before the trap handler. If return is executed during a DEBUG trap, the last command used to determine the status is the last command executed by the trap handler before return was invoked. If return is used outside a function, but during execution of a script by the . (source) command, it causes the shell to stop executing that script and return either n or the exit status of the last command executed within the script as the exit status of the script. If n is supplied, the return value is its least significant 8 bits. The return status is non-zero if return is supplied a non-numeric argument, or is used outside a function and not during execution of a script by . or source. Any command associated with the RETURN trap is executed before execution resumes after the function or script. set [-abefhkmnptuvxBCEHPT] [-o option-name] [--] [-] [arg ...] set [+abefhkmnptuvxBCEHPT] [+o option-name] [--] [-] [arg ...] Without options, display the name and value of each shell variable in a format that can be reused as input for setting or resetting the currently-set variables. Read- only variables cannot be reset. In posix mode, only shell variables are listed. The output is sorted according to the current locale. When options are specified, they set or unset shell attributes. Any arguments remaining after option processing are treated as values for the positional parameters and are assigned, in order, to $1, $2, ... $n. Options, if specified, have the following meanings: -a Each variable or function that is created or modified is given the export attribute and marked for export to the environment of subsequent commands. -b Report the status of terminated background jobs immediately, rather than before the next primary prompt. This is effective only when job control is enabled. -e Exit immediately if a pipeline (which may consist of a single simple command), a list, or a compound command (see SHELL GRAMMAR above), exits with a non-zero status. The shell does not exit if the command that fails is part of the command list immediately following a while or until keyword, part of the test following the if or elif reserved words, part of any command executed in a && or || list except the command following the final && or ||, any command in a pipeline but the last, or if the command's return value is being inverted with !. If a compound command other than a subshell returns a non-zero status because a command failed while -e was being ignored, the shell does not exit. A trap on ERR, if set, is executed before the shell exits. This option applies to the shell environment and each subshell environment separately (see COMMAND EXECUTION ENVIRONMENT above), and may cause subshells to exit before executing all the commands in the subshell. If a compound command or shell function executes in a context where -e is being ignored, none of the commands executed within the compound command or function body will be affected by the -e setting, even if -e is set and a command returns a failure status. If a compound command or shell function sets -e while executing in a context where -e is ignored, that setting will not have any effect until the compound command or the command containing the function call completes. -f Disable pathname expansion. -h Remember the location of commands as they are looked up for execution. This is enabled by default. -k All arguments in the form of assignment statements are placed in the environment for a command, not just those that precede the command name. -m Monitor mode. Job control is enabled. This option is on by default for interactive shells on systems that support it (see JOB CONTROL above). All processes run in a separate process group. When a background job completes, the shell prints a line containing its exit status. -n Read commands but do not execute them. This may be used to check a shell script for syntax errors. This is ignored by interactive shells. -o option-name The option-name can be one of the following: allexport Same as -a. braceexpand Same as -B. emacs Use an emacs-style command line editing interface. This is enabled by default when the shell is interactive, unless the shell is started with the --noediting option. This also affects the editing interface used for read -e. errexit Same as -e. errtrace Same as -E. functrace Same as -T. hashall Same as -h. histexpand Same as -H. history Enable command history, as described above under HISTORY. This option is on by default in interactive shells. ignoreeof The effect is as if the shell command ``IGNOREEOF=10'' had been executed (see Shell Variables above). keyword Same as -k. monitor Same as -m. noclobber Same as -C. noexec Same as -n. noglob Same as -f. nolog Currently ignored. notify Same as -b. nounset Same as -u. onecmd Same as -t. physical Same as -P. pipefail If set, the return value of a pipeline is the value of the last (rightmost) command to exit with a non-zero status, or zero if all commands in the pipeline exit successfully. This option is disabled by default. posix Change the behavior of bash where the default operation differs from the POSIX standard to match the standard (posix mode). See SEE ALSO below for a reference to a document that details how posix mode affects bash's behavior. privileged Same as -p. verbose Same as -v. vi Use a vi-style command line editing interface. This also affects the editing interface used for read -e. xtrace Same as -x. If -o is supplied with no option-name, the values of the current options are printed. If +o is supplied with no option-name, a series of set commands to recreate the current option settings is displayed on the standard output. -p Turn on privileged mode. In this mode, the $ENV and $BASH_ENV files are not processed, shell functions are not inherited from the environment, and the SHELLOPTS, BASHOPTS, CDPATH, and GLOBIGNORE variables, if they appear in the environment, are ignored. If the shell is started with the effective user (group) id not equal to the real user (group) id, and the -p option is not supplied, these actions are taken and the effective user id is set to the real user id. If the -p option is supplied at startup, the effective user id is not reset. Turning this option off causes the effective user and group ids to be set to the real user and group ids. -r Enable restricted shell mode. This option cannot be unset once it has been set. -t Exit after reading and executing one command. -u Treat unset variables and parameters other than the special parameters "@" and "*", or array variables subscripted with "@" or "*", as an error when performing parameter expansion. If expansion is attempted on an unset variable or parameter, the shell prints an error message, and, if not interactive, exits with a non-zero status. -v Print shell input lines as they are read. -x After expanding each simple command, for command, case command, select command, or arithmetic for command, display the expanded value of PS4, followed by the command and its expanded arguments or associated word list. -B The shell performs brace expansion (see Brace Expansion above). This is on by default. -C If set, bash does not overwrite an existing file with the >, >&, and <> redirection operators. This may be overridden when creating output files by using the redirection operator >| instead of >. -E If set, any trap on ERR is inherited by shell functions, command substitutions, and commands executed in a subshell environment. The ERR trap is normally not inherited in such cases. -H Enable ! style history substitution. This option is on by default when the shell is interactive. -P If set, the shell does not resolve symbolic links when executing commands such as cd that change the current working directory. It uses the physical directory structure instead. By default, bash follows the logical chain of directories when performing commands which change the current directory. -T If set, any traps on DEBUG and RETURN are inherited by shell functions, command substitutions, and commands executed in a subshell environment. The DEBUG and RETURN traps are normally not inherited in such cases. -- If no arguments follow this option, then the positional parameters are unset. Otherwise, the positional parameters are set to the args, even if some of them begin with a -. - Signal the end of options, cause all remaining args to be assigned to the positional parameters. The -x and -v options are turned off. If there are no args, the positional parameters remain unchanged. The options are off by default unless otherwise noted. Using + rather than - causes these options to be turned off. The options can also be specified as arguments to an invocation of the shell. The current set of options may be found in $-. The return status is always true unless an invalid option is encountered. shift [n] The positional parameters from n+1 ... are renamed to $1 .... Parameters represented by the numbers $# down to $#-n+1 are unset. n must be a non-negative number less than or equal to $#. If n is 0, no parameters are changed. If n is not given, it is assumed to be 1. If n is greater than $#, the positional parameters are not changed. The return status is greater than zero if n is greater than $# or less than zero; otherwise 0. shopt [-pqsu] [-o] [optname ...] Toggle the values of settings controlling optional shell behavior. The settings can be either those listed below, or, if the -o option is used, those available with the -o option to the set builtin command. With no options, or with the -p option, a list of all settable options is displayed, with an indication of whether or not each is set; if optnames are supplied, the output is restricted to those options. The -p option causes output to be displayed in a form that may be reused as input. Other options have the following meanings: -s Enable (set) each optname. -u Disable (unset) each optname. -q Suppresses normal output (quiet mode); the return status indicates whether the optname is set or unset. If multiple optname arguments are given with -q, the return status is zero if all optnames are enabled; non-zero otherwise. -o Restricts the values of optname to be those defined for the -o option to the set builtin. If either -s or -u is used with no optname arguments, shopt shows only those options which are set or unset, respectively. Unless otherwise noted, the shopt options are disabled (unset) by default. The return status when listing options is zero if all optnames are enabled, non-zero otherwise. When setting or unsetting options, the return status is zero unless an optname is not a valid shell option. The list of shopt options is: assoc_expand_once If set, the shell suppresses multiple evaluation of associative array subscripts during arithmetic expression evaluation, while executing builtins that can perform variable assignments, and while executing builtins that perform array dereferencing. autocd If set, a command name that is the name of a directory is executed as if it were the argument to the cd command. This option is only used by interactive shells. cdable_vars If set, an argument to the cd builtin command that is not a directory is assumed to be the name of a variable whose value is the directory to change to. cdspell If set, minor errors in the spelling of a directory component in a cd command will be corrected. The errors checked for are transposed characters, a missing character, and one character too many. If a correction is found, the corrected filename is printed, and the command proceeds. This option is only used by interactive shells. checkhash If set, bash checks that a command found in the hash table exists before trying to execute it. If a hashed command no longer exists, a normal path search is performed. checkjobs If set, bash lists the status of any stopped and running jobs before exiting an interactive shell. If any jobs are running, this causes the exit to be deferred until a second exit is attempted without an intervening command (see JOB CONTROL above). The shell always postpones exiting if any jobs are stopped. checkwinsize If set, bash checks the window size after each external (non-builtin) command and, if necessary, updates the values of LINES and COLUMNS. This option is enabled by default. cmdhist If set, bash attempts to save all lines of a multiple-line command in the same history entry. This allows easy re-editing of multi-line commands. This option is enabled by default, but only has an effect if command history is enabled, as described above under HISTORY. compat31 compat32 compat40 compat41 compat42 compat43 compat44 compat50 These control aspects of the shell's compatibility mode (see SHELL COMPATIBILITY MODE below). complete_fullquote If set, bash quotes all shell metacharacters in filenames and directory names when performing completion. If not set, bash removes metacharacters such as the dollar sign from the set of characters that will be quoted in completed filenames when these metacharacters appear in shell variable references in words to be completed. This means that dollar signs in variable names that expand to directories will not be quoted; however, any dollar signs appearing in filenames will not be quoted, either. This is active only when bash is using backslashes to quote completed filenames. This variable is set by default, which is the default bash behavior in versions through 4.2. direxpand If set, bash replaces directory names with the results of word expansion when performing filename completion. This changes the contents of the readline editing buffer. If not set, bash attempts to preserve what the user typed. dirspell If set, bash attempts spelling correction on directory names during word completion if the directory name initially supplied does not exist. dotglob If set, bash includes filenames beginning with a `.' in the results of pathname expansion. The filenames ``.'' and ``..'' must always be matched explicitly, even if dotglob is set. execfail If set, a non-interactive shell will not exit if it cannot execute the file specified as an argument to the exec builtin command. An interactive shell does not exit if exec fails. expand_aliases If set, aliases are expanded as described above under ALIASES. This option is enabled by default for interactive shells. extdebug If set at shell invocation, or in a shell startup file, arrange to execute the debugger profile before the shell starts, identical to the --debugger option. If set after invocation, behavior intended for use by debuggers is enabled: 1. The -F option to the declare builtin displays the source file name and line number corresponding to each function name supplied as an argument. 2. If the command run by the DEBUG trap returns a non-zero value, the next command is skipped and not executed. 3. If the command run by the DEBUG trap returns a value of 2, and the shell is executing in a subroutine (a shell function or a shell script executed by the . or source builtins), the shell simulates a call to return. 4. BASH_ARGC and BASH_ARGV are updated as described in their descriptions above). 5. Function tracing is enabled: command substitution, shell functions, and subshells invoked with ( command ) inherit the DEBUG and RETURN traps. 6. Error tracing is enabled: command substitution, shell functions, and subshells invoked with ( command ) inherit the ERR trap. extglob If set, the extended pattern matching features described above under Pathname Expansion are enabled. extquote If set, $'string' and $"string" quoting is performed within ${parameter} expansions enclosed in double quotes. This option is enabled by default. failglob If set, patterns which fail to match filenames during pathname expansion result in an expansion error. force_fignore If set, the suffixes specified by the FIGNORE shell variable cause words to be ignored when performing word completion even if the ignored words are the only possible completions. See SHELL VARIABLES above for a description of FIGNORE. This option is enabled by default. globasciiranges If set, range expressions used in pattern matching bracket expressions (see Pattern Matching above) behave as if in the traditional C locale when performing comparisons. That is, the current locale's collating sequence is not taken into account, so b will not collate between A and B, and upper-case and lower-case ASCII characters will collate together. globskipdots If set, pathname expansion will never match the filenames ``.'' and ``..'', even if the pattern begins with a ``.''. This option is enabled by default. globstar If set, the pattern ** used in a pathname expansion context will match all files and zero or more directories and subdirectories. If the pattern is followed by a /, only directories and subdirectories match. gnu_errfmt If set, shell error messages are written in the standard GNU error message format. histappend If set, the history list is appended to the file named by the value of the HISTFILE variable when the shell exits, rather than overwriting the file. histreedit If set, and readline is being used, a user is given the opportunity to re-edit a failed history substitution. histverify If set, and readline is being used, the results of history substitution are not immediately passed to the shell parser. Instead, the resulting line is loaded into the readline editing buffer, allowing further modification. hostcomplete If set, and readline is being used, bash will attempt to perform hostname completion when a word containing a @ is being completed (see Completing under READLINE above). This is enabled by default. huponexit If set, bash will send SIGHUP to all jobs when an interactive login shell exits. inherit_errexit If set, command substitution inherits the value of the errexit option, instead of unsetting it in the subshell environment. This option is enabled when posix mode is enabled. interactive_comments If set, allow a word beginning with # to cause that word and all remaining characters on that line to be ignored in an interactive shell (see COMMENTS above). This option is enabled by default. lastpipe If set, and job control is not active, the shell runs the last command of a pipeline not executed in the background in the current shell environment. lithist If set, and the cmdhist option is enabled, multi- line commands are saved to the history with embedded newlines rather than using semicolon separators where possible. localvar_inherit If set, local variables inherit the value and attributes of a variable of the same name that exists at a previous scope before any new value is assigned. The nameref attribute is not inherited. localvar_unset If set, calling unset on local variables in previous function scopes marks them so subsequent lookups find them unset until that function returns. This is identical to the behavior of unsetting local variables at the current function scope. login_shell The shell sets this option if it is started as a login shell (see INVOCATION above). The value may not be changed. mailwarn If set, and a file that bash is checking for mail has been accessed since the last time it was checked, the message ``The mail in mailfile has been read'' is displayed. no_empty_cmd_completion If set, and readline is being used, bash will not attempt to search the PATH for possible completions when completion is attempted on an empty line. nocaseglob If set, bash matches filenames in a case-insensitive fashion when performing pathname expansion (see Pathname Expansion above). nocasematch If set, bash matches patterns in a case-insensitive fashion when performing matching while executing case or [[ conditional commands, when performing pattern substitution word expansions, or when filtering possible completions as part of programmable completion. noexpand_translation If set, bash encloses the translated results of $"..." quoting in single quotes instead of double quotes. If the string is not translated, this has no effect. nullglob If set, bash allows patterns which match no files (see Pathname Expansion above) to expand to a null string, rather than themselves. patsub_replacement If set, bash expands occurrences of & in the replacement string of pattern substitution to the text matched by the pattern, as described under Parameter Expansion above. This option is enabled by default. progcomp If set, the programmable completion facilities (see Programmable Completion above) are enabled. This option is enabled by default. progcomp_alias If set, and programmable completion is enabled, bash treats a command name that doesn't have any completions as a possible alias and attempts alias expansion. If it has an alias, bash attempts programmable completion using the command word resulting from the expanded alias. promptvars If set, prompt strings undergo parameter expansion, command substitution, arithmetic expansion, and quote removal after being expanded as described in PROMPTING above. This option is enabled by default. restricted_shell The shell sets this option if it is started in restricted mode (see RESTRICTED SHELL below). The value may not be changed. This is not reset when the startup files are executed, allowing the startup files to discover whether or not a shell is restricted. shift_verbose If set, the shift builtin prints an error message when the shift count exceeds the number of positional parameters. sourcepath If set, the . (source) builtin uses the value of PATH to find the directory containing the file supplied as an argument. This option is enabled by default. varredir_close If set, the shell automatically closes file descriptors assigned using the {varname} redirection syntax (see REDIRECTION above) instead of leaving them open when the command completes. xpg_echo If set, the echo builtin expands backslash-escape sequences by default. suspend [-f] Suspend the execution of this shell until it receives a SIGCONT signal. A login shell, or a shell without job control enabled, cannot be suspended; the -f option can be used to override this and force the suspension. The return status is 0 unless the shell is a login shell or job control is not enabled and -f is not supplied. test expr [ expr ] Return a status of 0 (true) or 1 (false) depending on the evaluation of the conditional expression expr. Each operator and operand must be a separate argument. Expressions are composed of the primaries described above under CONDITIONAL EXPRESSIONS. test does not accept any options, nor does it accept and ignore an argument of -- as signifying the end of options. Expressions may be combined using the following operators, listed in decreasing order of precedence. The evaluation depends on the number of arguments; see below. Operator precedence is used when there are five or more arguments. ! expr True if expr is false. ( expr ) Returns the value of expr. This may be used to override the normal precedence of operators. expr1 -a expr2 True if both expr1 and expr2 are true. expr1 -o expr2 True if either expr1 or expr2 is true. test and [ evaluate conditional expressions using a set of rules based on the number of arguments. 0 arguments The expression is false. 1 argument The expression is true if and only if the argument is not null. 2 arguments If the first argument is !, the expression is true if and only if the second argument is null. If the first argument is one of the unary conditional operators listed above under CONDITIONAL EXPRESSIONS, the expression is true if the unary test is true. If the first argument is not a valid unary conditional operator, the expression is false. 3 arguments The following conditions are applied in the order listed. If the second argument is one of the binary conditional operators listed above under CONDITIONAL EXPRESSIONS, the result of the expression is the result of the binary test using the first and third arguments as operands. The -a and -o operators are considered binary operators when there are three arguments. If the first argument is !, the value is the negation of the two-argument test using the second and third arguments. If the first argument is exactly ( and the third argument is exactly ), the result is the one-argument test of the second argument. Otherwise, the expression is false. 4 arguments The following conditions are applied in the order listed. If the first argument is !, the result is the negation of the three-argument expression composed of the remaining arguments. the two- argument test using the second and third arguments. If the first argument is exactly ( and the fourth argument is exactly ), the result is the two- argument test of the second and third arguments. Otherwise, the expression is parsed and evaluated according to precedence using the rules listed above. 5 or more arguments The expression is parsed and evaluated according to precedence using the rules listed above. When used with test or [, the < and > operators sort lexicographically using ASCII ordering. times Print the accumulated user and system times for the shell and for processes run from the shell. The return status is 0. trap [-lp] [[arg] sigspec ...] The command arg is to be read and executed when the shell receives signal(s) sigspec. If arg is absent (and there is a single sigspec) or -, each specified signal is reset to its original disposition (the value it had upon entrance to the shell). If arg is the null string the signal specified by each sigspec is ignored by the shell and by the commands it invokes. If arg is not present and -p has been supplied, then the trap commands associated with each sigspec are displayed. If no arguments are supplied or if only -p is given, trap prints the list of commands associated with each signal. The -l option causes the shell to print a list of signal names and their corresponding numbers. Each sigspec is either a signal name defined in <signal.h>, or a signal number. Signal names are case insensitive and the SIG prefix is optional. If a sigspec is EXIT (0) the command arg is executed on exit from the shell. If a sigspec is DEBUG, the command arg is executed before every simple command, for command, case command, select command, every arithmetic for command, and before the first command executes in a shell function (see SHELL GRAMMAR above). Refer to the description of the extdebug option to the shopt builtin for details of its effect on the DEBUG trap. If a sigspec is RETURN, the command arg is executed each time a shell function or a script executed with the . or source builtins finishes executing. If a sigspec is ERR, the command arg is executed whenever a pipeline (which may consist of a single simple command), a list, or a compound command returns a non-zero exit status, subject to the following conditions. The ERR trap is not executed if the failed command is part of the command list immediately following a while or until keyword, part of the test in an if statement, part of a command executed in a && or || list except the command following the final && or ||, any command in a pipeline but the last, or if the command's return value is being inverted using !. These are the same conditions obeyed by the errexit (-e) option. Signals ignored upon entry to the shell cannot be trapped or reset. Trapped signals that are not being ignored are reset to their original values in a subshell or subshell environment when one is created. The return status is false if any sigspec is invalid; otherwise trap returns true. type [-aftpP] name [name ...] With no options, indicate how each name would be interpreted if used as a command name. If the -t option is used, type prints a string which is one of alias, keyword, function, builtin, or file if name is an alias, shell reserved word, function, builtin, or disk file, respectively. If the name is not found, then nothing is printed, and an exit status of false is returned. If the -p option is used, type either returns the name of the disk file that would be executed if name were specified as a command name, or nothing if ``type -t name'' would not return file. The -P option forces a PATH search for each name, even if ``type -t name'' would not return file. If a command is hashed, -p and -P print the hashed value, which is not necessarily the file that appears first in PATH. If the -a option is used, type prints all of the places that contain an executable named name. This includes aliases and functions, if and only if the -p option is not also used. The table of hashed commands is not consulted when using -a. The -f option suppresses shell function lookup, as with the command builtin. type returns true if all of the arguments are found, false if any are not found. ulimit [-HS] -a ulimit [-HS] [-bcdefiklmnpqrstuvxPRT [limit]] Provides control over the resources available to the shell and to processes started by it, on systems that allow such control. The -H and -S options specify that the hard or soft limit is set for the given resource. A hard limit cannot be increased by a non-root user once it is set; a soft limit may be increased up to the value of the hard limit. If neither -H nor -S is specified, both the soft and hard limits are set. The value of limit can be a number in the unit specified for the resource or one of the special values hard, soft, or unlimited, which stand for the current hard limit, the current soft limit, and no limit, respectively. If limit is omitted, the current value of the soft limit of the resource is printed, unless the -H option is given. When more than one resource is specified, the limit name and unit, if appropriate, are printed before the value. Other options are interpreted as follows: -a All current limits are reported; no limits are set -b The maximum socket buffer size -c The maximum size of core files created -d The maximum size of a process's data segment -e The maximum scheduling priority ("nice") -f The maximum size of files written by the shell and its children -i The maximum number of pending signals -k The maximum number of kqueues that may be allocated -l The maximum size that may be locked into memory -m The maximum resident set size (many systems do not honor this limit) -n The maximum number of open file descriptors (most systems do not allow this value to be set) -p The pipe size in 512-byte blocks (this may not be set) -q The maximum number of bytes in POSIX message queues -r The maximum real-time scheduling priority -s The maximum stack size -t The maximum amount of cpu time in seconds -u The maximum number of processes available to a single user -v The maximum amount of virtual memory available to the shell and, on some systems, to its children -x The maximum number of file locks -P The maximum number of pseudoterminals -R The maximum time a real-time process can run before blocking, in microseconds -T The maximum number of threads If limit is given, and the -a option is not used, limit is the new value of the specified resource. If no option is given, then -f is assumed. Values are in 1024-byte increments, except for -t, which is in seconds; -R, which is in microseconds; -p, which is in units of 512-byte blocks; -P, -T, -b, -k, -n, and -u, which are unscaled values; and, when in posix mode, -c and -f, which are in 512-byte increments. The return status is 0 unless an invalid option or argument is supplied, or an error occurs while setting a new limit. umask [-p] [-S] [mode] The user file-creation mask is set to mode. If mode begins with a digit, it is interpreted as an octal number; otherwise it is interpreted as a symbolic mode mask similar to that accepted by chmod(1). If mode is omitted, the current value of the mask is printed. The -S option causes the mask to be printed in symbolic form; the default output is an octal number. If the -p option is supplied, and mode is omitted, the output is in a form that may be reused as input. The return status is 0 if the mode was successfully changed or if no mode argument was supplied, and false otherwise. unalias [-a] [name ...] Remove each name from the list of defined aliases. If -a is supplied, all alias definitions are removed. The return value is true unless a supplied name is not a defined alias. unset [-fv] [-n] [name ...] For each name, remove the corresponding variable or function. If the -v option is given, each name refers to a shell variable, and that variable is removed. Read-only variables may not be unset. If -f is specified, each name refers to a shell function, and the function definition is removed. If the -n option is supplied, and name is a variable with the nameref attribute, name will be unset rather than the variable it references. -n has no effect if the -f option is supplied. If no options are supplied, each name refers to a variable; if there is no variable by that name, a function with that name, if any, is unset. Each unset variable or function is removed from the environment passed to subsequent commands. If any of BASH_ALIASES, BASH_ARGV0, BASH_CMDS, BASH_COMMAND, BASH_SUBSHELL, BASHPID, COMP_WORDBREAKS, DIRSTACK, EPOCHREALTIME, EPOCHSECONDS, FUNCNAME, GROUPS, HISTCMD, LINENO, RANDOM, SECONDS, or SRANDOM are unset, they lose their special properties, even if they are subsequently reset. The exit status is true unless a name is readonly or may not be unset. wait [-fn] [-p varname] [id ...] Wait for each specified child process and return its termination status. Each id may be a process ID or a job specification; if a job spec is given, all processes in that job's pipeline are waited for. If id is not given, wait waits for all running background jobs and the last- executed process substitution, if its process id is the same as $!, and the return status is zero. If the -n option is supplied, wait waits for a single job from the list of ids or, if no ids are supplied, any job, to complete and returns its exit status. If none of the supplied arguments is a child of the shell, or if no arguments are supplied and the shell has no unwaited-for children, the exit status is 127. If the -p option is supplied, the process or job identifier of the job for which the exit status is returned is assigned to the variable varname named by the option argument. The variable will be unset initially, before any assignment. This is useful only when the -n option is supplied. Supplying the -f option, when job control is enabled, forces wait to wait for id to terminate before returning its status, instead of returning when it changes status. If id specifies a non-existent process or job, the return status is 127. If wait is interrupted by a signal, the return status will be greater than 128, as described under SIGNALS above. Otherwise, the return status is the exit status of the last process or job waited for. SHELL COMPATIBILITY MODE top Bash-4.0 introduced the concept of a shell compatibility level, specified as a set of options to the shopt builtin ( compat31, compat32, compat40, compat41, and so on). There is only one current compatibility level -- each option is mutually exclusive. The compatibility level is intended to allow users to select behavior from previous versions that is incompatible with newer versions while they migrate scripts to use current features and behavior. It's intended to be a temporary solution. This section does not mention behavior that is standard for a particular version (e.g., setting compat32 means that quoting the rhs of the regexp matching operator quotes special regexp characters in the word, which is default behavior in bash-3.2 and subsequent versions). If a user enables, say, compat32, it may affect the behavior of other compatibility levels up to and including the current compatibility level. The idea is that each compatibility level controls behavior that changed in that version of bash, but that behavior may have been present in earlier versions. For instance, the change to use locale-based comparisons with the [[ command came in bash-4.1, and earlier versions used ASCII-based comparisons, so enabling compat32 will enable ASCII-based comparisons as well. That granularity may not be sufficient for all uses, and as a result users should employ compatibility levels carefully. Read the documentation for a particular feature to find out the current behavior. Bash-4.3 introduced a new shell variable: BASH_COMPAT. The value assigned to this variable (a decimal version number like 4.2, or an integer corresponding to the compatNN option, like 42) determines the compatibility level. Starting with bash-4.4, Bash has begun deprecating older compatibility levels. Eventually, the options will be removed in favor of BASH_COMPAT. Bash-5.0 is the final version for which there will be an individual shopt option for the previous version. Users should use BASH_COMPAT on bash-5.0 and later versions. The following table describes the behavior changes controlled by each compatibility level setting. The compatNN tag is used as shorthand for setting the compatibility level to NN using one of the following mechanisms. For versions prior to bash-5.0, the compatibility level may be set using the corresponding compatNN shopt option. For bash-4.3 and later versions, the BASH_COMPAT variable is preferred, and it is required for bash-5.1 and later versions. compat31 quoting the rhs of the [[ command's regexp matching operator (=~) has no special effect compat32 interrupting a command list such as "a ; b ; c" causes the execution of the next command in the list (in bash-4.0 and later versions, the shell acts as if it received the interrupt, so interrupting one command in a list aborts the execution of the entire list) compat40 the < and > operators to the [[ command do not consider the current locale when comparing strings; they use ASCII ordering. Bash versions prior to bash-4.1 use ASCII collation and strcmp(3); bash-4.1 and later use the current locale's collation sequence and strcoll(3). compat41 in posix mode, time may be followed by options and still be recognized as a reserved word (this is POSIX interpretation 267) in posix mode, the parser requires that an even number of single quotes occur in the word portion of a double-quoted parameter expansion and treats them specially, so that characters within the single quotes are considered quoted (this is POSIX interpretation 221) compat42 the replacement string in double-quoted pattern substitution does not undergo quote removal, as it does in versions after bash-4.2 in posix mode, single quotes are considered special when expanding the word portion of a double-quoted parameter expansion and can be used to quote a closing brace or other special character (this is part of POSIX interpretation 221); in later versions, single quotes are not special within double-quoted word expansions compat43 the shell does not print a warning message if an attempt is made to use a quoted compound assignment as an argument to declare (e.g., declare -a foo='(1 2)'). Later versions warn that this usage is deprecated word expansion errors are considered non-fatal errors that cause the current command to fail, even in posix mode (the default behavior is to make them fatal errors that cause the shell to exit) when executing a shell function, the loop state (while/until/etc.) is not reset, so break or continue in that function will break or continue loops in the calling context. Bash-4.4 and later reset the loop state to prevent this compat44 the shell sets up the values used by BASH_ARGV and BASH_ARGC so they can expand to the shell's positional parameters even if extended debugging mode is not enabled a subshell inherits loops from its parent context, so break or continue will cause the subshell to exit. Bash-5.0 and later reset the loop state to prevent the exit variable assignments preceding builtins like export and readonly that set attributes continue to affect variables with the same name in the calling environment even if the shell is not in posix mode compat50 Bash-5.1 changed the way $RANDOM is generated to introduce slightly more randomness. If the shell compatibility level is set to 50 or lower, it reverts to the method from bash-5.0 and previous versions, so seeding the random number generator by assigning a value to RANDOM will produce the same sequence as in bash-5.0 If the command hash table is empty, bash versions prior to bash-5.1 printed an informational message to that effect, even when producing output that can be reused as input. Bash-5.1 suppresses that message when the -l option is supplied. compat51 The unset builtin treats attempts to unset array subscripts @ and * differently depending on whether the array is indexed or associative, and differently than in previous versions. RESTRICTED SHELL top If bash is started with the name rbash, or the -r option is supplied at invocation, the shell becomes restricted. A restricted shell is used to set up an environment more controlled than the standard shell. It behaves identically to bash with the exception that the following are disallowed or not performed: changing directories with cd setting or unsetting the values of SHELL, PATH, HISTFILE, ENV, or BASH_ENV specifying command names containing / specifying a filename containing a / as an argument to the . builtin command specifying a filename containing a slash as an argument to the history builtin command specifying a filename containing a slash as an argument to the -p option to the hash builtin command importing function definitions from the shell environment at startup parsing the value of SHELLOPTS from the shell environment at startup redirecting output using the >, >|, <>, >&, &>, and >> redirection operators using the exec builtin command to replace the shell with another command adding or deleting builtin commands with the -f and -d options to the enable builtin command using the enable builtin command to enable disabled shell builtins specifying the -p option to the command builtin command turning off restricted mode with set +r or shopt -u restricted_shell. These restrictions are enforced after any startup files are read. When a command that is found to be a shell script is executed (see COMMAND EXECUTION above), rbash turns off any restrictions in the shell spawned to execute the script. SEE ALSO top Bash Reference Manual, Brian Fox and Chet Ramey The Gnu Readline Library, Brian Fox and Chet Ramey The Gnu History Library, Brian Fox and Chet Ramey Portable Operating System Interface (POSIX) Part 2: Shell and Utilities, IEEE -- http://pubs.opengroup.org/onlinepubs/9699919799/ http://tiswww.case.edu/~chet/bash/POSIX -- a description of posix mode sh(1), ksh(1), csh(1) emacs(1), vi(1) readline(3) FILES top /bin/bash The bash executable /etc/profile The systemwide initialization file, executed for login shells ~/.bash_profile The personal initialization file, executed for login shells ~/.bashrc The individual per-interactive-shell startup file ~/.bash_logout The individual login shell cleanup file, executed when a login shell exits ~/.bash_history The default value of HISTFILE, the file in which bash saves the command history ~/.inputrc Individual readline initialization file AUTHORS top Brian Fox, Free Software Foundation bfox@gnu.org Chet Ramey, Case Western Reserve University chet.ramey@case.edu BUG REPORTS top If you find a bug in bash, you should report it. But first, you should make sure that it really is a bug, and that it appears in the latest version of bash. The latest version is always available from ftp://ftp.gnu.org/pub/gnu/bash/ and http://git.savannah.gnu.org/cgit/bash.git/snapshot/bash- master.tar.gz. Once you have determined that a bug actually exists, use the bashbug command to submit a bug report. If you have a fix, you are encouraged to mail that as well! Suggestions and `philosophical' bug reports may be mailed to bug-bash@gnu.org or posted to the Usenet newsgroup gnu.bash.bug. ALL bug reports should include: The version number of bash The hardware and operating system The compiler used to compile A description of the bug behaviour A short script or `recipe' which exercises the bug bashbug inserts the first three items automatically into the template it provides for filing a bug report. Comments and bug reports concerning this manual page should be directed to chet.ramey@case.edu. BUGS top It's too big and too slow. There are some subtle differences between bash and traditional versions of sh, mostly because of the POSIX specification. Aliases are confusing in some uses. Shell builtin commands and functions are not stoppable/restartable. Compound commands and command sequences of the form `a ; b ; c' are not handled gracefully when process suspension is attempted. When a process is stopped, the shell immediately executes the next command in the sequence. It suffices to place the sequence of commands between parentheses to force it into a subshell, which may be stopped as a unit. Array variables may not (yet) be exported. There may be only one active coprocess at a time. COLOPHON top This page is part of the bash (Bourne again shell) project. Information about the project can be found at http://www.gnu.org/software/bash/. If you have a bug report for this manual page, see http://www.gnu.org/software/bash/. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/bash.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-14.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU Bash 5.2 2022 September 19 BASH(1) Pages that refer to this page: getopt(1), intro(1), kill(1), pmdabash(1), pv(1), quilt(1), systemctl(1), systemd-notify(1), systemd-run(1), time(1), setpgid(2), getopt(3), history(3), readline(3), strcmp(3), termios(3), ulimit(3), core(5), credentials(7), environ(7), suffixes(7), time_namespaces(7), cupsenable(8), dpkg-fsys-usrunmess(8), wg(8), wg-quick(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Decompress 'file.gz' to standard output and execute the output in bash Bash Command:<START>gzip -d --stdout file.gz | bash<END>

Decompress and extract '/usr/src/redhat/SOURCES/source-one.tar.gz'

gzip -dc /usr/src/redhat/SOURCES/source-one.tar.gz | tar -xvvf -

['tar']

Output a Bash command to accomplish the following task. Task: Decompress and extract '/usr/src/redhat/SOURCES/source-one.tar.gz' Bash Command:<START>gzip -dc /usr/src/redhat/SOURCES/source-one.tar.gz | tar -xvvf -<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # tar\n\n> Archiving utility.\n> Often combined with a compression method, such as `gzip` or `bzip2`.\n> More information: <https://www.gnu.org/software/tar>.\n\n- [c]reate an archive and write it to a [f]ile:\n\n`tar cf {{path/to/target.tar}} {{path/to/file1 path/to/file2 ...}}`\n\n- [c]reate a g[z]ipped archive and write it to a [f]ile:\n\n`tar czf {{path/to/target.tar.gz}} {{path/to/file1 path/to/file2 ...}}`\n\n- [c]reate a g[z]ipped archive from a directory using relative paths:\n\n`tar czf {{path/to/target.tar.gz}} --directory={{path/to/directory}} .`\n\n- E[x]tract a (compressed) archive [f]ile into the current directory [v]erbosely:\n\n`tar xvf {{path/to/source.tar[.gz|.bz2|.xz]}}`\n\n- E[x]tract a (compressed) archive [f]ile into the target directory:\n\n`tar xf {{path/to/source.tar[.gz|.bz2|.xz]}} --directory={{path/to/directory}}`\n\n- [c]reate a compressed archive and write it to a [f]ile, using the file extension to [a]utomatically determine the compression program:\n\n`tar caf {{path/to/target.tar.xz}} {{path/to/file1 path/to/file2 ...}}`\n\n- Lis[t] the contents of a tar [f]ile [v]erbosely:\n\n`tar tvf {{path/to/source.tar}}`\n\n- E[x]tract files matching a pattern from an archive [f]ile:\n\n`tar xf {{path/to/source.tar}} --wildcards "{{*.html}}"`\n Task: Decompress and extract '/usr/src/redhat/SOURCES/source-one.tar.gz' Bash Command:<START>gzip -dc /usr/src/redhat/SOURCES/source-one.tar.gz | tar -xvvf -<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: tar(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training tar(1) Linux manual page NAME | SYNOPSIS | NOTE | DESCRIPTION | OPTIONS | RETURN VALUE | SEE ALSO | BUG REPORTS | COPYRIGHT | COLOPHON TAR(1) GNU TAR Manual TAR(1) NAME top tar - an archiving utility SYNOPSIS top Traditional usage tar {A|c|d|r|t|u|x}[GnSkUWOmpsMBiajJzZhPlRvwo] [ARG...] UNIX-style usage tar -A [OPTIONS] -f ARCHIVE ARCHIVE... tar -c [-f ARCHIVE] [OPTIONS] [FILE...] tar -d [-f ARCHIVE] [OPTIONS] [FILE...] tar -r [-f ARCHIVE] [OPTIONS] [FILE...] tar -t [-f ARCHIVE] [OPTIONS] [MEMBER...] tar -u [-f ARCHIVE] [OPTIONS] [FILE...] tar -x [-f ARCHIVE] [OPTIONS] [MEMBER...] GNU-style usage tar {--catenate|--concatenate} [OPTIONS] --file ARCHIVE ARCHIVE... tar --create [--file ARCHIVE] [OPTIONS] [FILE...] tar {--diff|--compare} [--file ARCHIVE] [OPTIONS] [FILE...] tar --delete [--file ARCHIVE] [OPTIONS] [MEMBER...] tar --append [--file ARCHIVE] [OPTIONS] [FILE...] tar --list [--file ARCHIVE] [OPTIONS] [MEMBER...] tar --test-label [--file ARCHIVE] [OPTIONS] [LABEL...] tar --update [--file ARCHIVE] [OPTIONS] [FILE...] tar {--extract|--get} [--file ARCHIVE] [OPTIONS] [MEMBER...] NOTE top This manpage is a short description of GNU tar. For a detailed discussion, including examples and usage recommendations, refer to the GNU Tar Manual available in texinfo format. If the info reader and the tar documentation are properly installed on your system, the command info tar should give you access to the complete manual. You can also view the manual using the info mode in emacs(1), or find it in various formats online at https://www.gnu.org/software/tar/manual If any discrepancies occur between this manpage and the GNU Tar Manual, the later shall be considered the authoritative source. DESCRIPTION top GNU tar is an archiving program designed to store multiple files in a single file (an archive), and to manipulate such archives. The archive can be either a regular file or a device (e.g. a tape drive, hence the name of the program, which stands for tape archiver), which can be located either on the local or on a remote machine. Option styles Options to GNU tar can be given in three different styles. In traditional style, the first argument is a cluster of option letters and all subsequent arguments supply arguments to those options that require them. The arguments are read in the same order as the option letters. Any command line words that remain after all options have been processed are treated as non-option arguments: file or archive member names. For example, the c option requires creating the archive, the v option requests the verbose operation, and the f option takes an argument that sets the name of the archive to operate upon. The following command, written in the traditional style, instructs tar to store all files from the directory /etc into the archive file etc.tar, verbosely listing the files being archived: tar cfv etc.tar /etc In UNIX or short-option style, each option letter is prefixed with a single dash, as in other command line utilities. If an option takes an argument, the argument follows it, either as a separate command line word, or immediately following the option. However, if the option takes an optional argument, the argument must follow the option letter without any intervening whitespace, as in -g/tmp/snar.db. Any number of options not taking arguments can be clustered together after a single dash, e.g. -vkp. An option that takes an argument (whether mandatory or optional) can appear at the end of such a cluster, e.g. -vkpf a.tar. The example command above written in the short-option style could look like: tar -cvf etc.tar /etc or tar -c -v -f etc.tar /etc In GNU or long-option style, each option begins with two dashes and has a meaningful name, consisting of lower-case letters and dashes. When used, the long option can be abbreviated to its initial letters, provided that this does not create ambiguity. Arguments to long options are supplied either as a separate command line word, immediately following the option, or separated from the option by an equals sign with no intervening whitespace. Optional arguments must always use the latter method. Here are several ways of writing the example command in this style: tar --create --file etc.tar --verbose /etc or (abbreviating some options): tar --cre --file=etc.tar --verb /etc The options in all three styles can be intermixed, although doing so with old options is not encouraged. Operation mode The options listed in the table below tell GNU tar what operation it is to perform. Exactly one of them must be given. The meaning of non-option arguments depends on the operation mode requested. -A, --catenate, --concatenate Append archives to the end of another archive. The arguments are treated as the names of archives to append. All archives must be of the same format as the archive they are appended to, otherwise the resulting archive might be unusable with non-GNU implementations of tar. Notice also that when more than one archive is given, the members from archives other than the first one will be accessible in the resulting archive only when using the -i (--ignore-zeros) option. Compressed archives cannot be concatenated. -c, --create Create a new archive. Arguments supply the names of the files to be archived. Directories are archived recursively, unless the --no-recursion option is given. -d, --diff, --compare Find differences between archive and file system. The arguments are optional and specify archive members to compare. If not given, the current working directory is assumed. --delete Delete from the archive. The arguments supply names of the archive members to be removed. At least one argument must be given. This option does not operate on compressed archives. There is no short option equivalent. -r, --append Append files to the end of an archive. Arguments have the same meaning as for -c (--create). -t, --list List the contents of an archive. Arguments are optional. When given, they specify the names of the members to list. --test-label Test the archive volume label and exit. When used without arguments, it prints the volume label (if any) and exits with status 0. When one or more command line arguments are given. tar compares the volume label with each argument. It exits with code 0 if a match is found, and with code 1 otherwise. No output is displayed, unless used together with the -v (--verbose) option. There is no short option equivalent for this option. -u, --update Append files which are newer than the corresponding copy in the archive. Arguments have the same meaning as with the -c and -r options. Notice, that newer files don't replace their old archive copies, but instead are appended to the end of archive. The resulting archive can thus contain several members of the same name, corresponding to various versions of the same file. -x, --extract, --get Extract files from an archive. Arguments are optional. When given, they specify names of the archive members to be extracted. --show-defaults Show built-in defaults for various tar options and exit. -?, --help Display a short option summary and exit. --usage Display a list of available options and exit. --version Print program version and copyright information and exit. OPTIONS top Operation modifiers --check-device Check device numbers when creating incremental archives (default). -g, --listed-incremental=FILE Handle new GNU-format incremental backups. FILE is the name of a snapshot file, where tar stores additional information which is used to decide which files changed since the previous incremental dump and, consequently, must be dumped again. If FILE does not exist when creating an archive, it will be created and all files will be added to the resulting archive (the level 0 dump). To create incremental archives of non-zero level N, you need a copy of the snapshot file created for level N-1, and use it as FILE. When listing or extracting, the actual content of FILE is not inspected, it is needed only due to syntactical requirements. It is therefore common practice to use /dev/null in its place. --hole-detection=METHOD Use METHOD to detect holes in sparse files. This option implies --sparse. Valid values for METHOD are seek and raw. Default is seek with fallback to raw when not applicable. -G, --incremental Handle old GNU-format incremental backups. --ignore-failed-read Do not exit with nonzero on unreadable files. --level=NUMBER Set dump level for a created listed-incremental archive. Currently only --level=0 is meaningful: it instructs tar to truncate the snapshot file before dumping, thereby forcing a level 0 dump. -n, --seek Assume the archive is seekable. Normally tar determines automatically whether the archive can be seeked or not. This option is intended for use in cases when such recognition fails. It takes effect only if the archive is open for reading (e.g. with --list or --extract options). --no-check-device Do not check device numbers when creating incremental archives. --no-seek Assume the archive is not seekable. --occurrence[=N] Process only the Nth occurrence of each file in the archive. This option is valid only when used with one of the following subcommands: --delete, --diff, --extract or --list and when a list of files is given either on the command line or via the -T option. The default N is 1. --restrict Disable the use of some potentially harmful options. --sparse-version=MAJOR[.MINOR] Set which version of the sparse format to use. This option implies --sparse. Valid argument values are 0.0, 0.1, and 1.0. For a detailed discussion of sparse formats, refer to the GNU Tar Manual, appendix D, "Sparse Formats". Using the info reader, it can be accessed running the following command: info tar 'Sparse Formats'. -S, --sparse Handle sparse files efficiently. Some files in the file system may have segments which were actually never written (quite often these are database files created by such systems as DBM). When given this option, tar attempts to determine if the file is sparse prior to archiving it, and if so, to reduce the resulting archive size by not dumping empty parts of the file. Overwrite control These options control tar actions when extracting a file over an existing copy on disk. -k, --keep-old-files Don't replace existing files when extracting. --keep-newer-files Don't replace existing files that are newer than their archive copies. --keep-directory-symlink Don't replace existing symlinks to directories when extracting. --no-overwrite-dir Preserve metadata of existing directories. --one-top-level[=DIR] Extract all files into DIR, or, if used without argument, into a subdirectory named by the base name of the archive (minus standard compression suffixes recognizable by --auto-compress). --overwrite Overwrite existing files when extracting. --overwrite-dir Overwrite metadata of existing directories when extracting (default). --recursive-unlink Recursively remove all files in the directory prior to extracting it. --remove-files Remove files from disk after adding them to the archive. --skip-old-files Don't replace existing files when extracting, silently skip over them. -U, --unlink-first Remove each file prior to extracting over it. -W, --verify Verify the archive after writing it. Output stream selection --ignore-command-error Ignore subprocess exit codes. --no-ignore-command-error Treat non-zero exit codes of children as error (default). -O, --to-stdout Extract files to standard output. --to-command=COMMAND Pipe extracted files to COMMAND. The argument is the pathname of an external program, optionally with command line arguments. The program will be invoked and the contents of the file being extracted supplied to it on its standard input. Additional data will be supplied via the following environment variables: TAR_FILETYPE Type of the file. It is a single letter with the following meaning: f Regular file d Directory l Symbolic link h Hard link b Block device c Character device Currently only regular files are supported. TAR_MODE File mode, an octal number. TAR_FILENAME The name of the file. TAR_REALNAME Name of the file as stored in the archive. TAR_UNAME Name of the file owner. TAR_GNAME Name of the file owner group. TAR_ATIME Time of last access. It is a decimal number, representing seconds since the Epoch. If the archive provides times with nanosecond precision, the nanoseconds are appended to the timestamp after a decimal point. TAR_MTIME Time of last modification. TAR_CTIME Time of last status change. TAR_SIZE Size of the file. TAR_UID UID of the file owner. TAR_GID GID of the file owner. Additionally, the following variables contain information about tar operation mode and the archive being processed: TAR_VERSION GNU tar version number. TAR_ARCHIVE The name of the archive tar is processing. TAR_BLOCKING_FACTOR Current blocking factor, i.e. number of 512-byte blocks in a record. TAR_VOLUME Ordinal number of the volume tar is processing (set if reading a multi-volume archive). TAR_FORMAT Format of the archive being processed. One of: gnu, oldgnu, posix, ustar, v7. TAR_SUBCOMMAND A short option (with a leading dash) describing the operation tar is executing. Handling of file attributes --atime-preserve[=METHOD] Preserve access times on dumped files, either by restoring the times after reading (METHOD=replace, this is the default) or by not setting the times in the first place (METHOD=system). --delay-directory-restore Delay setting modification times and permissions of extracted directories until the end of extraction. Use this option when extracting from an archive which has unusual member ordering. --group=NAME[:GID] Force NAME as group for added files. If GID is not supplied, NAME can be either a user name or numeric GID. In this case the missing part (GID or name) will be inferred from the current host's group database. When used with --group-map=FILE, affects only those files whose owner group is not listed in FILE. --group-map=FILE Read group translation map from FILE. Empty lines are ignored. Comments are introduced with # sign and extend to the end of line. Each non-empty line in FILE defines translation for a single group. It must consist of two fields, delimited by any amount of whitespace: OLDGRP NEWGRP[:NEWGID] OLDGRP is either a valid group name or a GID prefixed with +. Unless NEWGID is supplied, NEWGRP must also be either a valid group name or a +GID. Otherwise, both NEWGRP and NEWGID need not be listed in the system group database. As a result, each input file with owner group OLDGRP will be stored in archive with owner group NEWGRP and GID NEWGID. --mode=CHANGES Force symbolic mode CHANGES for added files. --mtime=DATE-OR-FILE Set mtime for added files. DATE-OR-FILE is either a date/time in almost arbitrary format, or the name of an existing file. In the latter case the mtime of that file will be used. -m, --touch Don't extract file modified time. --no-delay-directory-restore Cancel the effect of the prior --delay-directory-restore option. --no-same-owner Extract files as yourself (default for ordinary users). --no-same-permissions Apply the user's umask when extracting permissions from the archive (default for ordinary users). --numeric-owner Always use numbers for user/group names. --owner=NAME[:UID] Force NAME as owner for added files. If UID is not supplied, NAME can be either a user name or numeric UID. In this case the missing part (UID or name) will be inferred from the current host's user database. When used with --owner-map=FILE, affects only those files whose owner is not listed in FILE. --owner-map=FILE Read owner translation map from FILE. Empty lines are ignored. Comments are introduced with # sign and extend to the end of line. Each non-empty line in FILE defines translation for a single UID. It must consist of two fields, delimited by any amount of whitespace: OLDUSR NEWUSR[:NEWUID] OLDUSR is either a valid user name or a UID prefixed with +. Unless NEWUID is supplied, NEWUSR must also be either a valid user name or a +UID. Otherwise, both NEWUSR and NEWUID need not be listed in the system user database. As a result, each input file owned by OLDUSR will be stored in archive with owner name NEWUSR and UID NEWUID. -p, --preserve-permissions, --same-permissions Set permissions of extracted files to those recorded in the archive (default for superuser). --same-owner Try extracting files with the same ownership as exists in the archive (default for superuser). -s, --preserve-order, --same-order Tell tar that the list of file names to process is sorted in the same order as the files in the archive. --sort=ORDER When creating an archive, sort directory entries according to ORDER, which is one of none, name, or inode. The default is --sort=none, which stores archive members in the same order as returned by the operating system. Using --sort=name ensures the member ordering in the created archive is uniform and reproducible. Using --sort=inode reduces the number of disk seeks made when creating the archive and thus can considerably speed up archivation. This sorting order is supported only if the underlying system provides the necessary information. Extended file attributes --acls Enable POSIX ACLs support. --no-acls Disable POSIX ACLs support. --selinux Enable SELinux context support. --no-selinux Disable SELinux context support. --xattrs Enable extended attributes support. --no-xattrs Disable extended attributes support. --xattrs-exclude=PATTERN Specify the exclude pattern for xattr keys. PATTERN is a globbing pattern, e.g. --xattrs-exclude='user.*' to include only attributes from the user namespace. --xattrs-include=PATTERN Specify the include pattern for xattr keys. PATTERN is a globbing pattern. Device selection and switching -f, --file=ARCHIVE Use archive file or device ARCHIVE. If this option is not given, tar will first examine the environment variable `TAPE'. If it is set, its value will be used as the archive name. Otherwise, tar will assume the compiled-in default. The default value can be inspected either using the --show-defaults option, or at the end of the tar --help output. An archive name that has a colon in it specifies a file or device on a remote machine. The part before the colon is taken as the machine name or IP address, and the part after it as the file or device pathname, e.g.: --file=remotehost:/dev/sr0 An optional username can be prefixed to the hostname, placing a @ sign between them. By default, the remote host is accessed via the rsh(1) command. Nowadays it is common to use ssh(1) instead. You can do so by giving the following command line option: --rsh-command=/usr/bin/ssh The remote machine should have the rmt(8) command installed. If its pathname does not match tar's default, you can inform tar about the correct pathname using the --rmt-command option. --force-local Archive file is local even if it has a colon. -F, --info-script=COMMAND, --new-volume-script=COMMAND Run COMMAND at the end of each tape (implies -M). The command can include arguments. When started, it will inherit tar's environment plus the following variables: TAR_VERSION GNU tar version number. TAR_ARCHIVE The name of the archive tar is processing. TAR_BLOCKING_FACTOR Current blocking factor, i.e. number of 512-byte blocks in a record. TAR_VOLUME Ordinal number of the volume tar is processing (set if reading a multi-volume archive). TAR_FORMAT Format of the archive being processed. One of: gnu, oldgnu, posix, ustar, v7. TAR_SUBCOMMAND A short option (with a leading dash) describing the operation tar is executing. TAR_FD File descriptor which can be used to communicate the new volume name to tar. If the info script fails, tar exits; otherwise, it begins writing the next volume. -L, --tape-length=N Change tape after writing Nx1024 bytes. If N is followed by a size suffix (see the subsection Size suffixes below), the suffix specifies the multiplicative factor to be used instead of 1024. This option implies -M. -M, --multi-volume Create/list/extract multi-volume archive. --rmt-command=COMMAND Use COMMAND instead of rmt when accessing remote archives. See the description of the -f option, above. --rsh-command=COMMAND Use COMMAND instead of rsh when accessing remote archives. See the description of the -f option, above. --volno-file=FILE When this option is used in conjunction with --multi-volume, tar will keep track of which volume of a multi-volume archive it is working in FILE. Device blocking -b, --blocking-factor=BLOCKS Set record size to BLOCKSx512 bytes. -B, --read-full-records When listing or extracting, accept incomplete input records after end-of-file marker. -i, --ignore-zeros Ignore zeroed blocks in archive. Normally two consecutive 512-blocks filled with zeroes mean EOF and tar stops reading after encountering them. This option instructs it to read further and is useful when reading archives created with the -A option. --record-size=NUMBER Set record size. NUMBER is the number of bytes per record. It must be multiple of 512. It can can be suffixed with a size suffix, e.g. --record-size=10K, for 10 Kilobytes. See the subsection Size suffixes, for a list of valid suffixes. Archive format selection -H, --format=FORMAT Create archive of the given format. Valid formats are: gnu GNU tar 1.13.x format oldgnu GNU format as per tar <= 1.12. pax, posix POSIX 1003.1-2001 (pax) format. ustar POSIX 1003.1-1988 (ustar) format. v7 Old V7 tar format. --old-archive, --portability Same as --format=v7. --pax-option=keyword[[:]=value][,keyword[[:]=value]]... Control pax keywords when creating PAX archives (-H pax). This option is equivalent to the -o option of the pax(1) utility. --posix Same as --format=posix. -V, --label=TEXT Create archive with volume name TEXT. If listing or extracting, use TEXT as a globbing pattern for volume name. Compression options -a, --auto-compress Use archive suffix to determine the compression program. -I, --use-compress-program=COMMAND Filter data through COMMAND. It must accept the -d option, for decompression. The argument can contain command line options. -j, --bzip2 Filter the archive through bzip2(1). -J, --xz Filter the archive through xz(1). --lzip Filter the archive through lzip(1). --lzma Filter the archive through lzma(1). --lzop Filter the archive through lzop(1). --no-auto-compress Do not use archive suffix to determine the compression program. -z, --gzip, --gunzip, --ungzip Filter the archive through gzip(1). -Z, --compress, --uncompress Filter the archive through compress(1). --zstd Filter the archive through zstd(1). Local file selection --add-file=FILE Add FILE to the archive (useful if its name starts with a dash). --backup[=CONTROL] Backup before removal. The CONTROL argument, if supplied, controls the backup policy. Its valid values are: none, off Never make backups. t, numbered Make numbered backups. nil, existing Make numbered backups if numbered backups exist, simple backups otherwise. never, simple Always make simple backups If CONTROL is not given, the value is taken from the VERSION_CONTROL environment variable. If it is not set, existing is assumed. -C, --directory=DIR Change to DIR before performing any operations. This option is order-sensitive, i.e. it affects all options that follow. --exclude=PATTERN Exclude files matching PATTERN, a glob(3)-style wildcard pattern. --exclude-backups Exclude backup and lock files. --exclude-caches Exclude contents of directories containing file CACHEDIR.TAG, except for the tag file itself. --exclude-caches-all Exclude directories containing file CACHEDIR.TAG and the file itself. --exclude-caches-under Exclude everything under directories containing CACHEDIR.TAG --exclude-ignore=FILE Before dumping a directory, see if it contains FILE. If so, read exclusion patterns from this file. The patterns affect only the directory itself. --exclude-ignore-recursive=FILE Same as --exclude-ignore, except that patterns from FILE affect both the directory and all its subdirectories. --exclude-tag=FILE Exclude contents of directories containing FILE, except for FILE itself. --exclude-tag-all=FILE Exclude directories containing FILE. --exclude-tag-under=FILE Exclude everything under directories containing FILE. --exclude-vcs Exclude version control system directories. --exclude-vcs-ignores Exclude files that match patterns read from VCS-specific ignore files. Supported files are: .cvsignore, .gitignore, .bzrignore, and .hgignore. -h, --dereference Follow symlinks; archive and dump the files they point to. --hard-dereference Follow hard links; archive and dump the files they refer to. -K, --starting-file=MEMBER Begin at the given member in the archive. --newer-mtime=DATE Work on files whose data changed after the DATE. If DATE starts with / or . it is taken to be a file name; the mtime of that file is used as the date. --no-null Disable the effect of the previous --null option. --no-recursion Avoid descending automatically in directories. --no-unquote Do not unquote input file or member names. --no-verbatim-files-from Treat each line read from a file list as if it were supplied in the command line. I.e., leading and trailing whitespace is removed and, if the resulting string begins with a dash, it is treated as tar command line option. This is the default behavior. The --no-verbatim-files-from option is provided as a way to restore it after --verbatim-files-from option. This option is positional: it affects all --files-from options that occur after it in, until --verbatim-files-from option or end of line, whichever occurs first. It is implied by the --no-null option. --null Instruct subsequent -T options to read null-terminated names verbatim (disables special handling of names that start with a dash). See also --verbatim-files-from. -N, --newer=DATE, --after-date=DATE Only store files newer than DATE. If DATE starts with / or . it is taken to be a file name; the mtime of that file is used as the date. --one-file-system Stay in local file system when creating archive. -P, --absolute-names Don't strip leading slashes from file names when creating archives. --recursion Recurse into directories (default). --suffix=STRING Backup before removal, override usual suffix. Default suffix is ~, unless overridden by environment variable SIMPLE_BACKUP_SUFFIX. -T, --files-from=FILE Get names to extract or create from FILE. Unless specified otherwise, the FILE must contain a list of names separated by ASCII LF (i.e. one name per line). The names read are handled the same way as command line arguments. They undergo quote removal and word splitting, and any string that starts with a - is handled as tar command line option. If this behavior is undesirable, it can be turned off using the --verbatim-files-from option. The --null option instructs tar that the names in FILE are separated by ASCII NUL character, instead of LF. It is useful if the list is generated by find(1) -print0 predicate. --unquote Unquote file or member names (default). --verbatim-files-from Treat each line obtained from a file list as a file name, even if it starts with a dash. File lists are supplied with the --files-from (-T) option. The default behavior is to handle names supplied in file lists as if they were typed in the command line, i.e. any names starting with a dash are treated as tar options. The --verbatim-files-from option disables this behavior. This option affects all --files-from options that occur after it in the command line. Its effect is reverted by the --no-verbatim-files-from option. This option is implied by the --null option. See also --add-file. -X, --exclude-from=FILE Exclude files matching patterns listed in FILE. File name transformations --strip-components=NUMBER Strip NUMBER leading components from file names on extraction. --transform=EXPRESSION, --xform=EXPRESSION Use sed replace EXPRESSION to transform file names. File name matching options These options affect both exclude and include patterns. --anchored Patterns match file name start. --ignore-case Ignore case. --no-anchored Patterns match after any / (default for exclusion). --no-ignore-case Case sensitive matching (default). --no-wildcards Verbatim string matching. --no-wildcards-match-slash Wildcards do not match /. --wildcards Use wildcards (default for exclusion). --wildcards-match-slash Wildcards match / (default for exclusion). Informative output --checkpoint[=N] Display progress messages every Nth record (default 10). --checkpoint-action=ACTION Run ACTION on each checkpoint. --clamp-mtime Only set time when the file is more recent than what was given with --mtime. --full-time Print file time to its full resolution. --index-file=FILE Send verbose output to FILE. -l, --check-links Print a message if not all links are dumped. --no-quote-chars=STRING Disable quoting for characters from STRING. --quote-chars=STRING Additionally quote characters from STRING. --quoting-style=STYLE Set quoting style for file and member names. Valid values for STYLE are literal, shell, shell-always, c, c-maybe, escape, locale, clocale. -R, --block-number Show block number within archive with each message. --show-omitted-dirs When listing or extracting, list each directory that does not match search criteria. --show-transformed-names, --show-stored-names Show file or archive names after transformation by --strip and --transform options. --totals[=SIGNAL] Print total bytes after processing the archive. If SIGNAL is given, print total bytes when this signal is delivered. Allowed signals are: SIGHUP, SIGQUIT, SIGINT, SIGUSR1, and SIGUSR2. The SIG prefix can be omitted. --utc Print file modification times in UTC. -v, --verbose Verbosely list files processed. Each instance of this option on the command line increases the verbosity level by one. The maximum verbosity level is 3. For a detailed discussion of how various verbosity levels affect tar's output, please refer to GNU Tar Manual, subsection 2.5.2 "The '--verbose' Option". --warning=KEYWORD Enable or disable warning messages identified by KEYWORD. The messages are suppressed if KEYWORD is prefixed with no- and enabled otherwise. Multiple --warning options accumulate. Keywords controlling general tar operation: all Enable all warning messages. This is the default. none Disable all warning messages. filename-with-nuls "%s: file name read contains nul character" alone-zero-block "A lone zero block at %s" Keywords applicable for tar --create: cachedir "%s: contains a cache directory tag %s; %s" file-shrank "%s: File shrank by %s bytes; padding with zeros" xdev "%s: file is on a different filesystem; not dumped" file-ignored "%s: Unknown file type; file ignored" "%s: socket ignored" "%s: door ignored" file-unchanged "%s: file is unchanged; not dumped" ignore-archive "%s: archive cannot contain itself; not dumped" file-removed "%s: File removed before we read it" file-changed "%s: file changed as we read it" failed-read Suppresses warnings about unreadable files or directories. This keyword applies only if used together with the --ignore-failed-read option. Keywords applicable for tar --extract: existing-file "%s: skipping existing file" timestamp "%s: implausibly old time stamp %s" "%s: time stamp %s is %s s in the future" contiguous-cast "Extracting contiguous files as regular files" symlink-cast "Attempting extraction of symbolic links as hard links" unknown-cast "%s: Unknown file type '%c', extracted as normal file" ignore-newer "Current %s is newer or same age" unknown-keyword "Ignoring unknown extended header keyword '%s'" decompress-program Controls verbose description of failures occurring when trying to run alternative decompressor programs. This warning is disabled by default (unless --verbose is used). A common example of what you can get when using this warning is: $ tar --warning=decompress-program -x -f archive.Z tar (child): cannot run compress: No such file or directory tar (child): trying gzip This means that tar first tried to decompress archive.Z using compress, and, when that failed, switched to gzip. record-size "Record size = %lu blocks" Keywords controlling incremental extraction: rename-directory "%s: Directory has been renamed from %s" "%s: Directory has been renamed" new-directory "%s: Directory is new" xdev "%s: directory is on a different device: not purging" bad-dumpdir "Malformed dumpdir: 'X' never used" -w, --interactive, --confirmation Ask for confirmation for every action. Compatibility options -o When creating, same as --old-archive. When extracting, same as --no-same-owner. Size suffixes Suffix Units Byte Equivalent b Blocks SIZE x 512 B Kilobytes SIZE x 1024 c Bytes SIZE G Gigabytes SIZE x 1024^3 K Kilobytes SIZE x 1024 k Kilobytes SIZE x 1024 M Megabytes SIZE x 1024^2 P Petabytes SIZE x 1024^5 T Terabytes SIZE x 1024^4 w Words SIZE x 2 RETURN VALUE top Tar's exit code indicates whether it was able to successfully perform the requested operation, and if not, what kind of error occurred. 0 Successful termination. 1 Some files differ. If tar was invoked with the --compare (--diff, -d) command line option, this means that some files in the archive differ from their disk counterparts. If tar was given one of the --create, --append or --update options, this exit code means that some files were changed while being archived and so the resulting archive does not contain the exact copy of the file set. 2 Fatal error. This means that some fatal, unrecoverable error occurred. If a subprocess that had been invoked by tar exited with a nonzero exit code, tar itself exits with that code as well. This can happen, for example, if a compression option (e.g. -z) was used and the external compressor program failed. Another example is rmt failure during backup to a remote device. SEE ALSO top bzip2(1), compress(1), gzip(1), lzma(1), lzop(1), rmt(8), symlink(7), xz(1), zstd(1). Complete tar manual: run info tar or use emacs(1) info mode to read it. Online copies of GNU tar documentation in various formats can be found at: https://www.gnu.org/software/tar/manual BUG REPORTS top Report bugs to <bug-tar@gnu.org>. COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. COLOPHON top This page is part of the tar (an archiver program) project. Information about the project can be found at http://savannah.gnu.org/projects/tar/. If you have a bug report for this manual page, see http://savannah.gnu.org/bugs/?group=tar. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/tar.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-09-12.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org TAR July 11, 2022 TAR(1) Pages that refer to this page: attr(1), dpkg-deb(1), dpkg-source(1), machinectl(1), rsync(1), st(4), suffixes(7), symlink(7), cupsd-helper(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Decompress and extract '/usr/src/redhat/SOURCES/source-one.tar.gz' Bash Command:<START>gzip -dc /usr/src/redhat/SOURCES/source-one.tar.gz | tar -xvvf -<END>

Decompress and extract 'libxml2-sources-2.7.7.tar.gz'

gzip -dc libxml2-sources-2.7.7.tar.gz | tar xvf -

['tar']

Output a Bash command to accomplish the following task. Task: Decompress and extract 'libxml2-sources-2.7.7.tar.gz' Bash Command:<START>gzip -dc libxml2-sources-2.7.7.tar.gz | tar xvf -<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # tar\n\n> Archiving utility.\n> Often combined with a compression method, such as `gzip` or `bzip2`.\n> More information: <https://www.gnu.org/software/tar>.\n\n- [c]reate an archive and write it to a [f]ile:\n\n`tar cf {{path/to/target.tar}} {{path/to/file1 path/to/file2 ...}}`\n\n- [c]reate a g[z]ipped archive and write it to a [f]ile:\n\n`tar czf {{path/to/target.tar.gz}} {{path/to/file1 path/to/file2 ...}}`\n\n- [c]reate a g[z]ipped archive from a directory using relative paths:\n\n`tar czf {{path/to/target.tar.gz}} --directory={{path/to/directory}} .`\n\n- E[x]tract a (compressed) archive [f]ile into the current directory [v]erbosely:\n\n`tar xvf {{path/to/source.tar[.gz|.bz2|.xz]}}`\n\n- E[x]tract a (compressed) archive [f]ile into the target directory:\n\n`tar xf {{path/to/source.tar[.gz|.bz2|.xz]}} --directory={{path/to/directory}}`\n\n- [c]reate a compressed archive and write it to a [f]ile, using the file extension to [a]utomatically determine the compression program:\n\n`tar caf {{path/to/target.tar.xz}} {{path/to/file1 path/to/file2 ...}}`\n\n- Lis[t] the contents of a tar [f]ile [v]erbosely:\n\n`tar tvf {{path/to/source.tar}}`\n\n- E[x]tract files matching a pattern from an archive [f]ile:\n\n`tar xf {{path/to/source.tar}} --wildcards "{{*.html}}"`\n Task: Decompress and extract 'libxml2-sources-2.7.7.tar.gz' Bash Command:<START>gzip -dc libxml2-sources-2.7.7.tar.gz | tar xvf -<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: tar(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training tar(1) Linux manual page NAME | SYNOPSIS | NOTE | DESCRIPTION | OPTIONS | RETURN VALUE | SEE ALSO | BUG REPORTS | COPYRIGHT | COLOPHON TAR(1) GNU TAR Manual TAR(1) NAME top tar - an archiving utility SYNOPSIS top Traditional usage tar {A|c|d|r|t|u|x}[GnSkUWOmpsMBiajJzZhPlRvwo] [ARG...] UNIX-style usage tar -A [OPTIONS] -f ARCHIVE ARCHIVE... tar -c [-f ARCHIVE] [OPTIONS] [FILE...] tar -d [-f ARCHIVE] [OPTIONS] [FILE...] tar -r [-f ARCHIVE] [OPTIONS] [FILE...] tar -t [-f ARCHIVE] [OPTIONS] [MEMBER...] tar -u [-f ARCHIVE] [OPTIONS] [FILE...] tar -x [-f ARCHIVE] [OPTIONS] [MEMBER...] GNU-style usage tar {--catenate|--concatenate} [OPTIONS] --file ARCHIVE ARCHIVE... tar --create [--file ARCHIVE] [OPTIONS] [FILE...] tar {--diff|--compare} [--file ARCHIVE] [OPTIONS] [FILE...] tar --delete [--file ARCHIVE] [OPTIONS] [MEMBER...] tar --append [--file ARCHIVE] [OPTIONS] [FILE...] tar --list [--file ARCHIVE] [OPTIONS] [MEMBER...] tar --test-label [--file ARCHIVE] [OPTIONS] [LABEL...] tar --update [--file ARCHIVE] [OPTIONS] [FILE...] tar {--extract|--get} [--file ARCHIVE] [OPTIONS] [MEMBER...] NOTE top This manpage is a short description of GNU tar. For a detailed discussion, including examples and usage recommendations, refer to the GNU Tar Manual available in texinfo format. If the info reader and the tar documentation are properly installed on your system, the command info tar should give you access to the complete manual. You can also view the manual using the info mode in emacs(1), or find it in various formats online at https://www.gnu.org/software/tar/manual If any discrepancies occur between this manpage and the GNU Tar Manual, the later shall be considered the authoritative source. DESCRIPTION top GNU tar is an archiving program designed to store multiple files in a single file (an archive), and to manipulate such archives. The archive can be either a regular file or a device (e.g. a tape drive, hence the name of the program, which stands for tape archiver), which can be located either on the local or on a remote machine. Option styles Options to GNU tar can be given in three different styles. In traditional style, the first argument is a cluster of option letters and all subsequent arguments supply arguments to those options that require them. The arguments are read in the same order as the option letters. Any command line words that remain after all options have been processed are treated as non-option arguments: file or archive member names. For example, the c option requires creating the archive, the v option requests the verbose operation, and the f option takes an argument that sets the name of the archive to operate upon. The following command, written in the traditional style, instructs tar to store all files from the directory /etc into the archive file etc.tar, verbosely listing the files being archived: tar cfv etc.tar /etc In UNIX or short-option style, each option letter is prefixed with a single dash, as in other command line utilities. If an option takes an argument, the argument follows it, either as a separate command line word, or immediately following the option. However, if the option takes an optional argument, the argument must follow the option letter without any intervening whitespace, as in -g/tmp/snar.db. Any number of options not taking arguments can be clustered together after a single dash, e.g. -vkp. An option that takes an argument (whether mandatory or optional) can appear at the end of such a cluster, e.g. -vkpf a.tar. The example command above written in the short-option style could look like: tar -cvf etc.tar /etc or tar -c -v -f etc.tar /etc In GNU or long-option style, each option begins with two dashes and has a meaningful name, consisting of lower-case letters and dashes. When used, the long option can be abbreviated to its initial letters, provided that this does not create ambiguity. Arguments to long options are supplied either as a separate command line word, immediately following the option, or separated from the option by an equals sign with no intervening whitespace. Optional arguments must always use the latter method. Here are several ways of writing the example command in this style: tar --create --file etc.tar --verbose /etc or (abbreviating some options): tar --cre --file=etc.tar --verb /etc The options in all three styles can be intermixed, although doing so with old options is not encouraged. Operation mode The options listed in the table below tell GNU tar what operation it is to perform. Exactly one of them must be given. The meaning of non-option arguments depends on the operation mode requested. -A, --catenate, --concatenate Append archives to the end of another archive. The arguments are treated as the names of archives to append. All archives must be of the same format as the archive they are appended to, otherwise the resulting archive might be unusable with non-GNU implementations of tar. Notice also that when more than one archive is given, the members from archives other than the first one will be accessible in the resulting archive only when using the -i (--ignore-zeros) option. Compressed archives cannot be concatenated. -c, --create Create a new archive. Arguments supply the names of the files to be archived. Directories are archived recursively, unless the --no-recursion option is given. -d, --diff, --compare Find differences between archive and file system. The arguments are optional and specify archive members to compare. If not given, the current working directory is assumed. --delete Delete from the archive. The arguments supply names of the archive members to be removed. At least one argument must be given. This option does not operate on compressed archives. There is no short option equivalent. -r, --append Append files to the end of an archive. Arguments have the same meaning as for -c (--create). -t, --list List the contents of an archive. Arguments are optional. When given, they specify the names of the members to list. --test-label Test the archive volume label and exit. When used without arguments, it prints the volume label (if any) and exits with status 0. When one or more command line arguments are given. tar compares the volume label with each argument. It exits with code 0 if a match is found, and with code 1 otherwise. No output is displayed, unless used together with the -v (--verbose) option. There is no short option equivalent for this option. -u, --update Append files which are newer than the corresponding copy in the archive. Arguments have the same meaning as with the -c and -r options. Notice, that newer files don't replace their old archive copies, but instead are appended to the end of archive. The resulting archive can thus contain several members of the same name, corresponding to various versions of the same file. -x, --extract, --get Extract files from an archive. Arguments are optional. When given, they specify names of the archive members to be extracted. --show-defaults Show built-in defaults for various tar options and exit. -?, --help Display a short option summary and exit. --usage Display a list of available options and exit. --version Print program version and copyright information and exit. OPTIONS top Operation modifiers --check-device Check device numbers when creating incremental archives (default). -g, --listed-incremental=FILE Handle new GNU-format incremental backups. FILE is the name of a snapshot file, where tar stores additional information which is used to decide which files changed since the previous incremental dump and, consequently, must be dumped again. If FILE does not exist when creating an archive, it will be created and all files will be added to the resulting archive (the level 0 dump). To create incremental archives of non-zero level N, you need a copy of the snapshot file created for level N-1, and use it as FILE. When listing or extracting, the actual content of FILE is not inspected, it is needed only due to syntactical requirements. It is therefore common practice to use /dev/null in its place. --hole-detection=METHOD Use METHOD to detect holes in sparse files. This option implies --sparse. Valid values for METHOD are seek and raw. Default is seek with fallback to raw when not applicable. -G, --incremental Handle old GNU-format incremental backups. --ignore-failed-read Do not exit with nonzero on unreadable files. --level=NUMBER Set dump level for a created listed-incremental archive. Currently only --level=0 is meaningful: it instructs tar to truncate the snapshot file before dumping, thereby forcing a level 0 dump. -n, --seek Assume the archive is seekable. Normally tar determines automatically whether the archive can be seeked or not. This option is intended for use in cases when such recognition fails. It takes effect only if the archive is open for reading (e.g. with --list or --extract options). --no-check-device Do not check device numbers when creating incremental archives. --no-seek Assume the archive is not seekable. --occurrence[=N] Process only the Nth occurrence of each file in the archive. This option is valid only when used with one of the following subcommands: --delete, --diff, --extract or --list and when a list of files is given either on the command line or via the -T option. The default N is 1. --restrict Disable the use of some potentially harmful options. --sparse-version=MAJOR[.MINOR] Set which version of the sparse format to use. This option implies --sparse. Valid argument values are 0.0, 0.1, and 1.0. For a detailed discussion of sparse formats, refer to the GNU Tar Manual, appendix D, "Sparse Formats". Using the info reader, it can be accessed running the following command: info tar 'Sparse Formats'. -S, --sparse Handle sparse files efficiently. Some files in the file system may have segments which were actually never written (quite often these are database files created by such systems as DBM). When given this option, tar attempts to determine if the file is sparse prior to archiving it, and if so, to reduce the resulting archive size by not dumping empty parts of the file. Overwrite control These options control tar actions when extracting a file over an existing copy on disk. -k, --keep-old-files Don't replace existing files when extracting. --keep-newer-files Don't replace existing files that are newer than their archive copies. --keep-directory-symlink Don't replace existing symlinks to directories when extracting. --no-overwrite-dir Preserve metadata of existing directories. --one-top-level[=DIR] Extract all files into DIR, or, if used without argument, into a subdirectory named by the base name of the archive (minus standard compression suffixes recognizable by --auto-compress). --overwrite Overwrite existing files when extracting. --overwrite-dir Overwrite metadata of existing directories when extracting (default). --recursive-unlink Recursively remove all files in the directory prior to extracting it. --remove-files Remove files from disk after adding them to the archive. --skip-old-files Don't replace existing files when extracting, silently skip over them. -U, --unlink-first Remove each file prior to extracting over it. -W, --verify Verify the archive after writing it. Output stream selection --ignore-command-error Ignore subprocess exit codes. --no-ignore-command-error Treat non-zero exit codes of children as error (default). -O, --to-stdout Extract files to standard output. --to-command=COMMAND Pipe extracted files to COMMAND. The argument is the pathname of an external program, optionally with command line arguments. The program will be invoked and the contents of the file being extracted supplied to it on its standard input. Additional data will be supplied via the following environment variables: TAR_FILETYPE Type of the file. It is a single letter with the following meaning: f Regular file d Directory l Symbolic link h Hard link b Block device c Character device Currently only regular files are supported. TAR_MODE File mode, an octal number. TAR_FILENAME The name of the file. TAR_REALNAME Name of the file as stored in the archive. TAR_UNAME Name of the file owner. TAR_GNAME Name of the file owner group. TAR_ATIME Time of last access. It is a decimal number, representing seconds since the Epoch. If the archive provides times with nanosecond precision, the nanoseconds are appended to the timestamp after a decimal point. TAR_MTIME Time of last modification. TAR_CTIME Time of last status change. TAR_SIZE Size of the file. TAR_UID UID of the file owner. TAR_GID GID of the file owner. Additionally, the following variables contain information about tar operation mode and the archive being processed: TAR_VERSION GNU tar version number. TAR_ARCHIVE The name of the archive tar is processing. TAR_BLOCKING_FACTOR Current blocking factor, i.e. number of 512-byte blocks in a record. TAR_VOLUME Ordinal number of the volume tar is processing (set if reading a multi-volume archive). TAR_FORMAT Format of the archive being processed. One of: gnu, oldgnu, posix, ustar, v7. TAR_SUBCOMMAND A short option (with a leading dash) describing the operation tar is executing. Handling of file attributes --atime-preserve[=METHOD] Preserve access times on dumped files, either by restoring the times after reading (METHOD=replace, this is the default) or by not setting the times in the first place (METHOD=system). --delay-directory-restore Delay setting modification times and permissions of extracted directories until the end of extraction. Use this option when extracting from an archive which has unusual member ordering. --group=NAME[:GID] Force NAME as group for added files. If GID is not supplied, NAME can be either a user name or numeric GID. In this case the missing part (GID or name) will be inferred from the current host's group database. When used with --group-map=FILE, affects only those files whose owner group is not listed in FILE. --group-map=FILE Read group translation map from FILE. Empty lines are ignored. Comments are introduced with # sign and extend to the end of line. Each non-empty line in FILE defines translation for a single group. It must consist of two fields, delimited by any amount of whitespace: OLDGRP NEWGRP[:NEWGID] OLDGRP is either a valid group name or a GID prefixed with +. Unless NEWGID is supplied, NEWGRP must also be either a valid group name or a +GID. Otherwise, both NEWGRP and NEWGID need not be listed in the system group database. As a result, each input file with owner group OLDGRP will be stored in archive with owner group NEWGRP and GID NEWGID. --mode=CHANGES Force symbolic mode CHANGES for added files. --mtime=DATE-OR-FILE Set mtime for added files. DATE-OR-FILE is either a date/time in almost arbitrary format, or the name of an existing file. In the latter case the mtime of that file will be used. -m, --touch Don't extract file modified time. --no-delay-directory-restore Cancel the effect of the prior --delay-directory-restore option. --no-same-owner Extract files as yourself (default for ordinary users). --no-same-permissions Apply the user's umask when extracting permissions from the archive (default for ordinary users). --numeric-owner Always use numbers for user/group names. --owner=NAME[:UID] Force NAME as owner for added files. If UID is not supplied, NAME can be either a user name or numeric UID. In this case the missing part (UID or name) will be inferred from the current host's user database. When used with --owner-map=FILE, affects only those files whose owner is not listed in FILE. --owner-map=FILE Read owner translation map from FILE. Empty lines are ignored. Comments are introduced with # sign and extend to the end of line. Each non-empty line in FILE defines translation for a single UID. It must consist of two fields, delimited by any amount of whitespace: OLDUSR NEWUSR[:NEWUID] OLDUSR is either a valid user name or a UID prefixed with +. Unless NEWUID is supplied, NEWUSR must also be either a valid user name or a +UID. Otherwise, both NEWUSR and NEWUID need not be listed in the system user database. As a result, each input file owned by OLDUSR will be stored in archive with owner name NEWUSR and UID NEWUID. -p, --preserve-permissions, --same-permissions Set permissions of extracted files to those recorded in the archive (default for superuser). --same-owner Try extracting files with the same ownership as exists in the archive (default for superuser). -s, --preserve-order, --same-order Tell tar that the list of file names to process is sorted in the same order as the files in the archive. --sort=ORDER When creating an archive, sort directory entries according to ORDER, which is one of none, name, or inode. The default is --sort=none, which stores archive members in the same order as returned by the operating system. Using --sort=name ensures the member ordering in the created archive is uniform and reproducible. Using --sort=inode reduces the number of disk seeks made when creating the archive and thus can considerably speed up archivation. This sorting order is supported only if the underlying system provides the necessary information. Extended file attributes --acls Enable POSIX ACLs support. --no-acls Disable POSIX ACLs support. --selinux Enable SELinux context support. --no-selinux Disable SELinux context support. --xattrs Enable extended attributes support. --no-xattrs Disable extended attributes support. --xattrs-exclude=PATTERN Specify the exclude pattern for xattr keys. PATTERN is a globbing pattern, e.g. --xattrs-exclude='user.*' to include only attributes from the user namespace. --xattrs-include=PATTERN Specify the include pattern for xattr keys. PATTERN is a globbing pattern. Device selection and switching -f, --file=ARCHIVE Use archive file or device ARCHIVE. If this option is not given, tar will first examine the environment variable `TAPE'. If it is set, its value will be used as the archive name. Otherwise, tar will assume the compiled-in default. The default value can be inspected either using the --show-defaults option, or at the end of the tar --help output. An archive name that has a colon in it specifies a file or device on a remote machine. The part before the colon is taken as the machine name or IP address, and the part after it as the file or device pathname, e.g.: --file=remotehost:/dev/sr0 An optional username can be prefixed to the hostname, placing a @ sign between them. By default, the remote host is accessed via the rsh(1) command. Nowadays it is common to use ssh(1) instead. You can do so by giving the following command line option: --rsh-command=/usr/bin/ssh The remote machine should have the rmt(8) command installed. If its pathname does not match tar's default, you can inform tar about the correct pathname using the --rmt-command option. --force-local Archive file is local even if it has a colon. -F, --info-script=COMMAND, --new-volume-script=COMMAND Run COMMAND at the end of each tape (implies -M). The command can include arguments. When started, it will inherit tar's environment plus the following variables: TAR_VERSION GNU tar version number. TAR_ARCHIVE The name of the archive tar is processing. TAR_BLOCKING_FACTOR Current blocking factor, i.e. number of 512-byte blocks in a record. TAR_VOLUME Ordinal number of the volume tar is processing (set if reading a multi-volume archive). TAR_FORMAT Format of the archive being processed. One of: gnu, oldgnu, posix, ustar, v7. TAR_SUBCOMMAND A short option (with a leading dash) describing the operation tar is executing. TAR_FD File descriptor which can be used to communicate the new volume name to tar. If the info script fails, tar exits; otherwise, it begins writing the next volume. -L, --tape-length=N Change tape after writing Nx1024 bytes. If N is followed by a size suffix (see the subsection Size suffixes below), the suffix specifies the multiplicative factor to be used instead of 1024. This option implies -M. -M, --multi-volume Create/list/extract multi-volume archive. --rmt-command=COMMAND Use COMMAND instead of rmt when accessing remote archives. See the description of the -f option, above. --rsh-command=COMMAND Use COMMAND instead of rsh when accessing remote archives. See the description of the -f option, above. --volno-file=FILE When this option is used in conjunction with --multi-volume, tar will keep track of which volume of a multi-volume archive it is working in FILE. Device blocking -b, --blocking-factor=BLOCKS Set record size to BLOCKSx512 bytes. -B, --read-full-records When listing or extracting, accept incomplete input records after end-of-file marker. -i, --ignore-zeros Ignore zeroed blocks in archive. Normally two consecutive 512-blocks filled with zeroes mean EOF and tar stops reading after encountering them. This option instructs it to read further and is useful when reading archives created with the -A option. --record-size=NUMBER Set record size. NUMBER is the number of bytes per record. It must be multiple of 512. It can can be suffixed with a size suffix, e.g. --record-size=10K, for 10 Kilobytes. See the subsection Size suffixes, for a list of valid suffixes. Archive format selection -H, --format=FORMAT Create archive of the given format. Valid formats are: gnu GNU tar 1.13.x format oldgnu GNU format as per tar <= 1.12. pax, posix POSIX 1003.1-2001 (pax) format. ustar POSIX 1003.1-1988 (ustar) format. v7 Old V7 tar format. --old-archive, --portability Same as --format=v7. --pax-option=keyword[[:]=value][,keyword[[:]=value]]... Control pax keywords when creating PAX archives (-H pax). This option is equivalent to the -o option of the pax(1) utility. --posix Same as --format=posix. -V, --label=TEXT Create archive with volume name TEXT. If listing or extracting, use TEXT as a globbing pattern for volume name. Compression options -a, --auto-compress Use archive suffix to determine the compression program. -I, --use-compress-program=COMMAND Filter data through COMMAND. It must accept the -d option, for decompression. The argument can contain command line options. -j, --bzip2 Filter the archive through bzip2(1). -J, --xz Filter the archive through xz(1). --lzip Filter the archive through lzip(1). --lzma Filter the archive through lzma(1). --lzop Filter the archive through lzop(1). --no-auto-compress Do not use archive suffix to determine the compression program. -z, --gzip, --gunzip, --ungzip Filter the archive through gzip(1). -Z, --compress, --uncompress Filter the archive through compress(1). --zstd Filter the archive through zstd(1). Local file selection --add-file=FILE Add FILE to the archive (useful if its name starts with a dash). --backup[=CONTROL] Backup before removal. The CONTROL argument, if supplied, controls the backup policy. Its valid values are: none, off Never make backups. t, numbered Make numbered backups. nil, existing Make numbered backups if numbered backups exist, simple backups otherwise. never, simple Always make simple backups If CONTROL is not given, the value is taken from the VERSION_CONTROL environment variable. If it is not set, existing is assumed. -C, --directory=DIR Change to DIR before performing any operations. This option is order-sensitive, i.e. it affects all options that follow. --exclude=PATTERN Exclude files matching PATTERN, a glob(3)-style wildcard pattern. --exclude-backups Exclude backup and lock files. --exclude-caches Exclude contents of directories containing file CACHEDIR.TAG, except for the tag file itself. --exclude-caches-all Exclude directories containing file CACHEDIR.TAG and the file itself. --exclude-caches-under Exclude everything under directories containing CACHEDIR.TAG --exclude-ignore=FILE Before dumping a directory, see if it contains FILE. If so, read exclusion patterns from this file. The patterns affect only the directory itself. --exclude-ignore-recursive=FILE Same as --exclude-ignore, except that patterns from FILE affect both the directory and all its subdirectories. --exclude-tag=FILE Exclude contents of directories containing FILE, except for FILE itself. --exclude-tag-all=FILE Exclude directories containing FILE. --exclude-tag-under=FILE Exclude everything under directories containing FILE. --exclude-vcs Exclude version control system directories. --exclude-vcs-ignores Exclude files that match patterns read from VCS-specific ignore files. Supported files are: .cvsignore, .gitignore, .bzrignore, and .hgignore. -h, --dereference Follow symlinks; archive and dump the files they point to. --hard-dereference Follow hard links; archive and dump the files they refer to. -K, --starting-file=MEMBER Begin at the given member in the archive. --newer-mtime=DATE Work on files whose data changed after the DATE. If DATE starts with / or . it is taken to be a file name; the mtime of that file is used as the date. --no-null Disable the effect of the previous --null option. --no-recursion Avoid descending automatically in directories. --no-unquote Do not unquote input file or member names. --no-verbatim-files-from Treat each line read from a file list as if it were supplied in the command line. I.e., leading and trailing whitespace is removed and, if the resulting string begins with a dash, it is treated as tar command line option. This is the default behavior. The --no-verbatim-files-from option is provided as a way to restore it after --verbatim-files-from option. This option is positional: it affects all --files-from options that occur after it in, until --verbatim-files-from option or end of line, whichever occurs first. It is implied by the --no-null option. --null Instruct subsequent -T options to read null-terminated names verbatim (disables special handling of names that start with a dash). See also --verbatim-files-from. -N, --newer=DATE, --after-date=DATE Only store files newer than DATE. If DATE starts with / or . it is taken to be a file name; the mtime of that file is used as the date. --one-file-system Stay in local file system when creating archive. -P, --absolute-names Don't strip leading slashes from file names when creating archives. --recursion Recurse into directories (default). --suffix=STRING Backup before removal, override usual suffix. Default suffix is ~, unless overridden by environment variable SIMPLE_BACKUP_SUFFIX. -T, --files-from=FILE Get names to extract or create from FILE. Unless specified otherwise, the FILE must contain a list of names separated by ASCII LF (i.e. one name per line). The names read are handled the same way as command line arguments. They undergo quote removal and word splitting, and any string that starts with a - is handled as tar command line option. If this behavior is undesirable, it can be turned off using the --verbatim-files-from option. The --null option instructs tar that the names in FILE are separated by ASCII NUL character, instead of LF. It is useful if the list is generated by find(1) -print0 predicate. --unquote Unquote file or member names (default). --verbatim-files-from Treat each line obtained from a file list as a file name, even if it starts with a dash. File lists are supplied with the --files-from (-T) option. The default behavior is to handle names supplied in file lists as if they were typed in the command line, i.e. any names starting with a dash are treated as tar options. The --verbatim-files-from option disables this behavior. This option affects all --files-from options that occur after it in the command line. Its effect is reverted by the --no-verbatim-files-from option. This option is implied by the --null option. See also --add-file. -X, --exclude-from=FILE Exclude files matching patterns listed in FILE. File name transformations --strip-components=NUMBER Strip NUMBER leading components from file names on extraction. --transform=EXPRESSION, --xform=EXPRESSION Use sed replace EXPRESSION to transform file names. File name matching options These options affect both exclude and include patterns. --anchored Patterns match file name start. --ignore-case Ignore case. --no-anchored Patterns match after any / (default for exclusion). --no-ignore-case Case sensitive matching (default). --no-wildcards Verbatim string matching. --no-wildcards-match-slash Wildcards do not match /. --wildcards Use wildcards (default for exclusion). --wildcards-match-slash Wildcards match / (default for exclusion). Informative output --checkpoint[=N] Display progress messages every Nth record (default 10). --checkpoint-action=ACTION Run ACTION on each checkpoint. --clamp-mtime Only set time when the file is more recent than what was given with --mtime. --full-time Print file time to its full resolution. --index-file=FILE Send verbose output to FILE. -l, --check-links Print a message if not all links are dumped. --no-quote-chars=STRING Disable quoting for characters from STRING. --quote-chars=STRING Additionally quote characters from STRING. --quoting-style=STYLE Set quoting style for file and member names. Valid values for STYLE are literal, shell, shell-always, c, c-maybe, escape, locale, clocale. -R, --block-number Show block number within archive with each message. --show-omitted-dirs When listing or extracting, list each directory that does not match search criteria. --show-transformed-names, --show-stored-names Show file or archive names after transformation by --strip and --transform options. --totals[=SIGNAL] Print total bytes after processing the archive. If SIGNAL is given, print total bytes when this signal is delivered. Allowed signals are: SIGHUP, SIGQUIT, SIGINT, SIGUSR1, and SIGUSR2. The SIG prefix can be omitted. --utc Print file modification times in UTC. -v, --verbose Verbosely list files processed. Each instance of this option on the command line increases the verbosity level by one. The maximum verbosity level is 3. For a detailed discussion of how various verbosity levels affect tar's output, please refer to GNU Tar Manual, subsection 2.5.2 "The '--verbose' Option". --warning=KEYWORD Enable or disable warning messages identified by KEYWORD. The messages are suppressed if KEYWORD is prefixed with no- and enabled otherwise. Multiple --warning options accumulate. Keywords controlling general tar operation: all Enable all warning messages. This is the default. none Disable all warning messages. filename-with-nuls "%s: file name read contains nul character" alone-zero-block "A lone zero block at %s" Keywords applicable for tar --create: cachedir "%s: contains a cache directory tag %s; %s" file-shrank "%s: File shrank by %s bytes; padding with zeros" xdev "%s: file is on a different filesystem; not dumped" file-ignored "%s: Unknown file type; file ignored" "%s: socket ignored" "%s: door ignored" file-unchanged "%s: file is unchanged; not dumped" ignore-archive "%s: archive cannot contain itself; not dumped" file-removed "%s: File removed before we read it" file-changed "%s: file changed as we read it" failed-read Suppresses warnings about unreadable files or directories. This keyword applies only if used together with the --ignore-failed-read option. Keywords applicable for tar --extract: existing-file "%s: skipping existing file" timestamp "%s: implausibly old time stamp %s" "%s: time stamp %s is %s s in the future" contiguous-cast "Extracting contiguous files as regular files" symlink-cast "Attempting extraction of symbolic links as hard links" unknown-cast "%s: Unknown file type '%c', extracted as normal file" ignore-newer "Current %s is newer or same age" unknown-keyword "Ignoring unknown extended header keyword '%s'" decompress-program Controls verbose description of failures occurring when trying to run alternative decompressor programs. This warning is disabled by default (unless --verbose is used). A common example of what you can get when using this warning is: $ tar --warning=decompress-program -x -f archive.Z tar (child): cannot run compress: No such file or directory tar (child): trying gzip This means that tar first tried to decompress archive.Z using compress, and, when that failed, switched to gzip. record-size "Record size = %lu blocks" Keywords controlling incremental extraction: rename-directory "%s: Directory has been renamed from %s" "%s: Directory has been renamed" new-directory "%s: Directory is new" xdev "%s: directory is on a different device: not purging" bad-dumpdir "Malformed dumpdir: 'X' never used" -w, --interactive, --confirmation Ask for confirmation for every action. Compatibility options -o When creating, same as --old-archive. When extracting, same as --no-same-owner. Size suffixes Suffix Units Byte Equivalent b Blocks SIZE x 512 B Kilobytes SIZE x 1024 c Bytes SIZE G Gigabytes SIZE x 1024^3 K Kilobytes SIZE x 1024 k Kilobytes SIZE x 1024 M Megabytes SIZE x 1024^2 P Petabytes SIZE x 1024^5 T Terabytes SIZE x 1024^4 w Words SIZE x 2 RETURN VALUE top Tar's exit code indicates whether it was able to successfully perform the requested operation, and if not, what kind of error occurred. 0 Successful termination. 1 Some files differ. If tar was invoked with the --compare (--diff, -d) command line option, this means that some files in the archive differ from their disk counterparts. If tar was given one of the --create, --append or --update options, this exit code means that some files were changed while being archived and so the resulting archive does not contain the exact copy of the file set. 2 Fatal error. This means that some fatal, unrecoverable error occurred. If a subprocess that had been invoked by tar exited with a nonzero exit code, tar itself exits with that code as well. This can happen, for example, if a compression option (e.g. -z) was used and the external compressor program failed. Another example is rmt failure during backup to a remote device. SEE ALSO top bzip2(1), compress(1), gzip(1), lzma(1), lzop(1), rmt(8), symlink(7), xz(1), zstd(1). Complete tar manual: run info tar or use emacs(1) info mode to read it. Online copies of GNU tar documentation in various formats can be found at: https://www.gnu.org/software/tar/manual BUG REPORTS top Report bugs to <bug-tar@gnu.org>. COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. COLOPHON top This page is part of the tar (an archiver program) project. Information about the project can be found at http://savannah.gnu.org/projects/tar/. If you have a bug report for this manual page, see http://savannah.gnu.org/bugs/?group=tar. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/tar.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-09-12.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org TAR July 11, 2022 TAR(1) Pages that refer to this page: attr(1), dpkg-deb(1), dpkg-source(1), machinectl(1), rsync(1), st(4), suffixes(7), symlink(7), cupsd-helper(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Decompress and extract 'libxml2-sources-2.7.7.tar.gz' Bash Command:<START>gzip -dc libxml2-sources-2.7.7.tar.gz | tar xvf -<END>

Decompress and sort "$part0" and "$part1" of files in different processes

sort -m <(zcat $part0 | sort) <(zcat $part1 | sort)

['zcat', 'sort']

Output a Bash command to accomplish the following task. Task: Decompress and sort "$part0" and "$part1" of files in different processes Bash Command:<START>sort -m <(zcat $part0 | sort) <(zcat $part1 | sort)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # zcat\n\n> Print data from `gzip` compressed files.\n> More information: <https://www.gnu.org/software/gzip/manual/gzip.html>.\n\n- Print the uncompressed contents of a `gzip` archive to `stdout`:\n\n`zcat {{file.txt.gz}}`\n\n- Print compression details of a `gzip` archive to `stdout`:\n\n`zcat -l {{file.txt.gz}}`\n # sort\n\n> Sort lines of text files.\n> More information: <https://www.gnu.org/software/coreutils/sort>.\n\n- Sort a file in ascending order:\n\n`sort {{path/to/file}}`\n\n- Sort a file in descending order:\n\n`sort --reverse {{path/to/file}}`\n\n- Sort a file in case-insensitive way:\n\n`sort --ignore-case {{path/to/file}}`\n\n- Sort a file using numeric rather than alphabetic order:\n\n`sort --numeric-sort {{path/to/file}}`\n\n- Sort `/etc/passwd` by the 3rd field of each line numerically, using ":" as a field separator:\n\n`sort --field-separator={{:}} --key={{3n}} {{/etc/passwd}}`\n\n- Sort a file preserving only unique lines:\n\n`sort --unique {{path/to/file}}`\n\n- Sort a file, printing the output to the specified output file (can be used to sort a file in-place):\n\n`sort --output={{path/to/file}} {{path/to/file}}`\n\n- Sort numbers with exponents:\n\n`sort --general-numeric-sort {{path/to/file}}`\n Task: Decompress and sort "$part0" and "$part1" of files in different processes Bash Command:<START>sort -m <(zcat $part0 | sort) <(zcat $part1 | sort)<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: zcat(1p) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training zcat(1p) Linux manual page PROLOG | NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | STDIN | INPUT FILES | ENVIRONMENT VARIABLES | ASYNCHRONOUS EVENTS | STDOUT | STDERR | OUTPUT FILES | EXTENDED DESCRIPTION | EXIT STATUS | CONSEQUENCES OF ERRORS | APPLICATION USAGE | EXAMPLES | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT ZCAT(1P) POSIX Programmer's Manual ZCAT(1P) PROLOG top This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux. NAME top zcat expand and concatenate data SYNOPSIS top zcat [file...] DESCRIPTION top The zcat utility shall write to standard output the uncompressed form of files that have been compressed using the compress utility. It is the equivalent of uncompress -c. Input files are not affected. OPTIONS top None. OPERANDS top The following operand shall be supported: file The pathname of a file previously processed by the compress utility. If file already has the .Z suffix specified, it is used as submitted. Otherwise, the .Z suffix is appended to the filename prior to processing. STDIN top The standard input shall be used only if no file operands are specified, or if a file operand is '-'. INPUT FILES top Input files shall be compressed files that are in the format produced by the compress utility. ENVIRONMENT VARIABLES top The following environment variables shall affect the execution of zcat: LANG Provide a default value for the internationalization variables that are unset or null. (See the Base Definitions volume of POSIX.12017, Section 8.2, Internationalization Variables for the precedence of internationalization variables used to determine the values of locale categories.) LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_CTYPE Determine the locale for the interpretation of sequences of bytes of text data as characters (for example, single-byte as opposed to multi-byte characters in arguments). LC_MESSAGES Determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error. NLSPATH Determine the location of message catalogs for the processing of LC_MESSAGES. ASYNCHRONOUS EVENTS top Default. STDOUT top The compressed files given as input shall be written on standard output in their uncompressed form. STDERR top The standard error shall be used only for diagnostic messages. OUTPUT FILES top None. EXTENDED DESCRIPTION top None. EXIT STATUS top The following exit values shall be returned: 0 Successful completion. >0 An error occurred. CONSEQUENCES OF ERRORS top Default. The following sections are informative. APPLICATION USAGE top None. EXAMPLES top None. RATIONALE top None. FUTURE DIRECTIONS top None. SEE ALSO top compress(1p), uncompress(1p) The Base Definitions volume of POSIX.12017, Chapter 8, Environment Variables COPYRIGHT top Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html . Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html . IEEE/The Open Group 2017 ZCAT(1P) Pages that refer to this page: compress(1p), uncompress(1p) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. sort(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training sort(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON SORT(1) User Commands SORT(1) NAME top sort - sort lines of text files SYNOPSIS top sort [OPTION]... [FILE]... sort [OPTION]... --files0-from=F DESCRIPTION top Write sorted concatenation of all FILE(s) to standard output. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. Ordering options: -b, --ignore-leading-blanks ignore leading blanks -d, --dictionary-order consider only blanks and alphanumeric characters -f, --ignore-case fold lower case to upper case characters -g, --general-numeric-sort compare according to general numerical value -i, --ignore-nonprinting consider only printable characters -M, --month-sort compare (unknown) < 'JAN' < ... < 'DEC' -h, --human-numeric-sort compare human readable numbers (e.g., 2K 1G) -n, --numeric-sort compare according to string numerical value -R, --random-sort shuffle, but group identical keys. See shuf(1) --random-source=FILE get random bytes from FILE -r, --reverse reverse the result of comparisons --sort=WORD sort according to WORD: general-numeric -g, human-numeric -h, month -M, numeric -n, random -R, version -V -V, --version-sort natural sort of (version) numbers within text Other options: --batch-size=NMERGE merge at most NMERGE inputs at once; for more use temp files -c, --check, --check=diagnose-first check for sorted input; do not sort -C, --check=quiet, --check=silent like -c, but do not report first bad line --compress-program=PROG compress temporaries with PROG; decompress them with PROG -d --debug annotate the part of the line used to sort, and warn about questionable usage to stderr --files0-from=F read input from the files specified by NUL-terminated names in file F; If F is - then read names from standard input -k, --key=KEYDEF sort via a key; KEYDEF gives location and type -m, --merge merge already sorted files; do not sort -o, --output=FILE write result to FILE instead of standard output -s, --stable stabilize sort by disabling last-resort comparison -S, --buffer-size=SIZE use SIZE for main memory buffer -t, --field-separator=SEP use SEP instead of non-blank to blank transition -T, --temporary-directory=DIR use DIR for temporaries, not $TMPDIR or /tmp; multiple options specify multiple directories --parallel=N change the number of sorts run concurrently to N -u, --unique with -c, check for strict ordering; without -c, output only the first of an equal run -z, --zero-terminated line delimiter is NUL, not newline --help display this help and exit --version output version information and exit KEYDEF is F[.C][OPTS][,F[.C][OPTS]] for start and stop position, where F is a field number and C a character position in the field; both are origin 1, and the stop position defaults to the line's end. If neither -t nor -b is in effect, characters in a field are counted from the beginning of the preceding whitespace. OPTS is one or more single-letter ordering options [bdfgiMhnRrV], which override global ordering options for that key. If no key is given, use the entire line as the key. Use --debug to diagnose incorrect key usage. SIZE may be followed by the following multiplicative suffixes: % 1% of memory, b 1, K 1024 (default), and so on for M, G, T, P, E, Z, Y, R, Q. *** WARNING *** The locale specified by the environment affects sort order. Set LC_ALL=C to get the traditional sort order that uses native byte values. AUTHOR top Written by Mike Haertel and Paul Eggert. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top shuf(1), uniq(1) Full documentation <https://www.gnu.org/software/coreutils/sort> or available locally via: info '(coreutils) sort invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 SORT(1) Pages that refer to this page: column(1), grep(1), look(1), prlimit(1), ps(1), uniq(1), qsort(3), environ(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Decompress and sort "$part0" and "$part1" of files in different processes Bash Command:<START>sort -m <(zcat $part0 | sort) <(zcat $part1 | sort)<END>

Decompress and unarchive "hello-0.2.tar.gz"

gzip -dc hello-0.2.tar.gz | tar -xf -

['tar']

Output a Bash command to accomplish the following task. Task: Decompress and unarchive "hello-0.2.tar.gz" Bash Command:<START>gzip -dc hello-0.2.tar.gz | tar -xf -<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # tar\n\n> Archiving utility.\n> Often combined with a compression method, such as `gzip` or `bzip2`.\n> More information: <https://www.gnu.org/software/tar>.\n\n- [c]reate an archive and write it to a [f]ile:\n\n`tar cf {{path/to/target.tar}} {{path/to/file1 path/to/file2 ...}}`\n\n- [c]reate a g[z]ipped archive and write it to a [f]ile:\n\n`tar czf {{path/to/target.tar.gz}} {{path/to/file1 path/to/file2 ...}}`\n\n- [c]reate a g[z]ipped archive from a directory using relative paths:\n\n`tar czf {{path/to/target.tar.gz}} --directory={{path/to/directory}} .`\n\n- E[x]tract a (compressed) archive [f]ile into the current directory [v]erbosely:\n\n`tar xvf {{path/to/source.tar[.gz|.bz2|.xz]}}`\n\n- E[x]tract a (compressed) archive [f]ile into the target directory:\n\n`tar xf {{path/to/source.tar[.gz|.bz2|.xz]}} --directory={{path/to/directory}}`\n\n- [c]reate a compressed archive and write it to a [f]ile, using the file extension to [a]utomatically determine the compression program:\n\n`tar caf {{path/to/target.tar.xz}} {{path/to/file1 path/to/file2 ...}}`\n\n- Lis[t] the contents of a tar [f]ile [v]erbosely:\n\n`tar tvf {{path/to/source.tar}}`\n\n- E[x]tract files matching a pattern from an archive [f]ile:\n\n`tar xf {{path/to/source.tar}} --wildcards "{{*.html}}"`\n Task: Decompress and unarchive "hello-0.2.tar.gz" Bash Command:<START>gzip -dc hello-0.2.tar.gz | tar -xf -<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: tar(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training tar(1) Linux manual page NAME | SYNOPSIS | NOTE | DESCRIPTION | OPTIONS | RETURN VALUE | SEE ALSO | BUG REPORTS | COPYRIGHT | COLOPHON TAR(1) GNU TAR Manual TAR(1) NAME top tar - an archiving utility SYNOPSIS top Traditional usage tar {A|c|d|r|t|u|x}[GnSkUWOmpsMBiajJzZhPlRvwo] [ARG...] UNIX-style usage tar -A [OPTIONS] -f ARCHIVE ARCHIVE... tar -c [-f ARCHIVE] [OPTIONS] [FILE...] tar -d [-f ARCHIVE] [OPTIONS] [FILE...] tar -r [-f ARCHIVE] [OPTIONS] [FILE...] tar -t [-f ARCHIVE] [OPTIONS] [MEMBER...] tar -u [-f ARCHIVE] [OPTIONS] [FILE...] tar -x [-f ARCHIVE] [OPTIONS] [MEMBER...] GNU-style usage tar {--catenate|--concatenate} [OPTIONS] --file ARCHIVE ARCHIVE... tar --create [--file ARCHIVE] [OPTIONS] [FILE...] tar {--diff|--compare} [--file ARCHIVE] [OPTIONS] [FILE...] tar --delete [--file ARCHIVE] [OPTIONS] [MEMBER...] tar --append [--file ARCHIVE] [OPTIONS] [FILE...] tar --list [--file ARCHIVE] [OPTIONS] [MEMBER...] tar --test-label [--file ARCHIVE] [OPTIONS] [LABEL...] tar --update [--file ARCHIVE] [OPTIONS] [FILE...] tar {--extract|--get} [--file ARCHIVE] [OPTIONS] [MEMBER...] NOTE top This manpage is a short description of GNU tar. For a detailed discussion, including examples and usage recommendations, refer to the GNU Tar Manual available in texinfo format. If the info reader and the tar documentation are properly installed on your system, the command info tar should give you access to the complete manual. You can also view the manual using the info mode in emacs(1), or find it in various formats online at https://www.gnu.org/software/tar/manual If any discrepancies occur between this manpage and the GNU Tar Manual, the later shall be considered the authoritative source. DESCRIPTION top GNU tar is an archiving program designed to store multiple files in a single file (an archive), and to manipulate such archives. The archive can be either a regular file or a device (e.g. a tape drive, hence the name of the program, which stands for tape archiver), which can be located either on the local or on a remote machine. Option styles Options to GNU tar can be given in three different styles. In traditional style, the first argument is a cluster of option letters and all subsequent arguments supply arguments to those options that require them. The arguments are read in the same order as the option letters. Any command line words that remain after all options have been processed are treated as non-option arguments: file or archive member names. For example, the c option requires creating the archive, the v option requests the verbose operation, and the f option takes an argument that sets the name of the archive to operate upon. The following command, written in the traditional style, instructs tar to store all files from the directory /etc into the archive file etc.tar, verbosely listing the files being archived: tar cfv etc.tar /etc In UNIX or short-option style, each option letter is prefixed with a single dash, as in other command line utilities. If an option takes an argument, the argument follows it, either as a separate command line word, or immediately following the option. However, if the option takes an optional argument, the argument must follow the option letter without any intervening whitespace, as in -g/tmp/snar.db. Any number of options not taking arguments can be clustered together after a single dash, e.g. -vkp. An option that takes an argument (whether mandatory or optional) can appear at the end of such a cluster, e.g. -vkpf a.tar. The example command above written in the short-option style could look like: tar -cvf etc.tar /etc or tar -c -v -f etc.tar /etc In GNU or long-option style, each option begins with two dashes and has a meaningful name, consisting of lower-case letters and dashes. When used, the long option can be abbreviated to its initial letters, provided that this does not create ambiguity. Arguments to long options are supplied either as a separate command line word, immediately following the option, or separated from the option by an equals sign with no intervening whitespace. Optional arguments must always use the latter method. Here are several ways of writing the example command in this style: tar --create --file etc.tar --verbose /etc or (abbreviating some options): tar --cre --file=etc.tar --verb /etc The options in all three styles can be intermixed, although doing so with old options is not encouraged. Operation mode The options listed in the table below tell GNU tar what operation it is to perform. Exactly one of them must be given. The meaning of non-option arguments depends on the operation mode requested. -A, --catenate, --concatenate Append archives to the end of another archive. The arguments are treated as the names of archives to append. All archives must be of the same format as the archive they are appended to, otherwise the resulting archive might be unusable with non-GNU implementations of tar. Notice also that when more than one archive is given, the members from archives other than the first one will be accessible in the resulting archive only when using the -i (--ignore-zeros) option. Compressed archives cannot be concatenated. -c, --create Create a new archive. Arguments supply the names of the files to be archived. Directories are archived recursively, unless the --no-recursion option is given. -d, --diff, --compare Find differences between archive and file system. The arguments are optional and specify archive members to compare. If not given, the current working directory is assumed. --delete Delete from the archive. The arguments supply names of the archive members to be removed. At least one argument must be given. This option does not operate on compressed archives. There is no short option equivalent. -r, --append Append files to the end of an archive. Arguments have the same meaning as for -c (--create). -t, --list List the contents of an archive. Arguments are optional. When given, they specify the names of the members to list. --test-label Test the archive volume label and exit. When used without arguments, it prints the volume label (if any) and exits with status 0. When one or more command line arguments are given. tar compares the volume label with each argument. It exits with code 0 if a match is found, and with code 1 otherwise. No output is displayed, unless used together with the -v (--verbose) option. There is no short option equivalent for this option. -u, --update Append files which are newer than the corresponding copy in the archive. Arguments have the same meaning as with the -c and -r options. Notice, that newer files don't replace their old archive copies, but instead are appended to the end of archive. The resulting archive can thus contain several members of the same name, corresponding to various versions of the same file. -x, --extract, --get Extract files from an archive. Arguments are optional. When given, they specify names of the archive members to be extracted. --show-defaults Show built-in defaults for various tar options and exit. -?, --help Display a short option summary and exit. --usage Display a list of available options and exit. --version Print program version and copyright information and exit. OPTIONS top Operation modifiers --check-device Check device numbers when creating incremental archives (default). -g, --listed-incremental=FILE Handle new GNU-format incremental backups. FILE is the name of a snapshot file, where tar stores additional information which is used to decide which files changed since the previous incremental dump and, consequently, must be dumped again. If FILE does not exist when creating an archive, it will be created and all files will be added to the resulting archive (the level 0 dump). To create incremental archives of non-zero level N, you need a copy of the snapshot file created for level N-1, and use it as FILE. When listing or extracting, the actual content of FILE is not inspected, it is needed only due to syntactical requirements. It is therefore common practice to use /dev/null in its place. --hole-detection=METHOD Use METHOD to detect holes in sparse files. This option implies --sparse. Valid values for METHOD are seek and raw. Default is seek with fallback to raw when not applicable. -G, --incremental Handle old GNU-format incremental backups. --ignore-failed-read Do not exit with nonzero on unreadable files. --level=NUMBER Set dump level for a created listed-incremental archive. Currently only --level=0 is meaningful: it instructs tar to truncate the snapshot file before dumping, thereby forcing a level 0 dump. -n, --seek Assume the archive is seekable. Normally tar determines automatically whether the archive can be seeked or not. This option is intended for use in cases when such recognition fails. It takes effect only if the archive is open for reading (e.g. with --list or --extract options). --no-check-device Do not check device numbers when creating incremental archives. --no-seek Assume the archive is not seekable. --occurrence[=N] Process only the Nth occurrence of each file in the archive. This option is valid only when used with one of the following subcommands: --delete, --diff, --extract or --list and when a list of files is given either on the command line or via the -T option. The default N is 1. --restrict Disable the use of some potentially harmful options. --sparse-version=MAJOR[.MINOR] Set which version of the sparse format to use. This option implies --sparse. Valid argument values are 0.0, 0.1, and 1.0. For a detailed discussion of sparse formats, refer to the GNU Tar Manual, appendix D, "Sparse Formats". Using the info reader, it can be accessed running the following command: info tar 'Sparse Formats'. -S, --sparse Handle sparse files efficiently. Some files in the file system may have segments which were actually never written (quite often these are database files created by such systems as DBM). When given this option, tar attempts to determine if the file is sparse prior to archiving it, and if so, to reduce the resulting archive size by not dumping empty parts of the file. Overwrite control These options control tar actions when extracting a file over an existing copy on disk. -k, --keep-old-files Don't replace existing files when extracting. --keep-newer-files Don't replace existing files that are newer than their archive copies. --keep-directory-symlink Don't replace existing symlinks to directories when extracting. --no-overwrite-dir Preserve metadata of existing directories. --one-top-level[=DIR] Extract all files into DIR, or, if used without argument, into a subdirectory named by the base name of the archive (minus standard compression suffixes recognizable by --auto-compress). --overwrite Overwrite existing files when extracting. --overwrite-dir Overwrite metadata of existing directories when extracting (default). --recursive-unlink Recursively remove all files in the directory prior to extracting it. --remove-files Remove files from disk after adding them to the archive. --skip-old-files Don't replace existing files when extracting, silently skip over them. -U, --unlink-first Remove each file prior to extracting over it. -W, --verify Verify the archive after writing it. Output stream selection --ignore-command-error Ignore subprocess exit codes. --no-ignore-command-error Treat non-zero exit codes of children as error (default). -O, --to-stdout Extract files to standard output. --to-command=COMMAND Pipe extracted files to COMMAND. The argument is the pathname of an external program, optionally with command line arguments. The program will be invoked and the contents of the file being extracted supplied to it on its standard input. Additional data will be supplied via the following environment variables: TAR_FILETYPE Type of the file. It is a single letter with the following meaning: f Regular file d Directory l Symbolic link h Hard link b Block device c Character device Currently only regular files are supported. TAR_MODE File mode, an octal number. TAR_FILENAME The name of the file. TAR_REALNAME Name of the file as stored in the archive. TAR_UNAME Name of the file owner. TAR_GNAME Name of the file owner group. TAR_ATIME Time of last access. It is a decimal number, representing seconds since the Epoch. If the archive provides times with nanosecond precision, the nanoseconds are appended to the timestamp after a decimal point. TAR_MTIME Time of last modification. TAR_CTIME Time of last status change. TAR_SIZE Size of the file. TAR_UID UID of the file owner. TAR_GID GID of the file owner. Additionally, the following variables contain information about tar operation mode and the archive being processed: TAR_VERSION GNU tar version number. TAR_ARCHIVE The name of the archive tar is processing. TAR_BLOCKING_FACTOR Current blocking factor, i.e. number of 512-byte blocks in a record. TAR_VOLUME Ordinal number of the volume tar is processing (set if reading a multi-volume archive). TAR_FORMAT Format of the archive being processed. One of: gnu, oldgnu, posix, ustar, v7. TAR_SUBCOMMAND A short option (with a leading dash) describing the operation tar is executing. Handling of file attributes --atime-preserve[=METHOD] Preserve access times on dumped files, either by restoring the times after reading (METHOD=replace, this is the default) or by not setting the times in the first place (METHOD=system). --delay-directory-restore Delay setting modification times and permissions of extracted directories until the end of extraction. Use this option when extracting from an archive which has unusual member ordering. --group=NAME[:GID] Force NAME as group for added files. If GID is not supplied, NAME can be either a user name or numeric GID. In this case the missing part (GID or name) will be inferred from the current host's group database. When used with --group-map=FILE, affects only those files whose owner group is not listed in FILE. --group-map=FILE Read group translation map from FILE. Empty lines are ignored. Comments are introduced with # sign and extend to the end of line. Each non-empty line in FILE defines translation for a single group. It must consist of two fields, delimited by any amount of whitespace: OLDGRP NEWGRP[:NEWGID] OLDGRP is either a valid group name or a GID prefixed with +. Unless NEWGID is supplied, NEWGRP must also be either a valid group name or a +GID. Otherwise, both NEWGRP and NEWGID need not be listed in the system group database. As a result, each input file with owner group OLDGRP will be stored in archive with owner group NEWGRP and GID NEWGID. --mode=CHANGES Force symbolic mode CHANGES for added files. --mtime=DATE-OR-FILE Set mtime for added files. DATE-OR-FILE is either a date/time in almost arbitrary format, or the name of an existing file. In the latter case the mtime of that file will be used. -m, --touch Don't extract file modified time. --no-delay-directory-restore Cancel the effect of the prior --delay-directory-restore option. --no-same-owner Extract files as yourself (default for ordinary users). --no-same-permissions Apply the user's umask when extracting permissions from the archive (default for ordinary users). --numeric-owner Always use numbers for user/group names. --owner=NAME[:UID] Force NAME as owner for added files. If UID is not supplied, NAME can be either a user name or numeric UID. In this case the missing part (UID or name) will be inferred from the current host's user database. When used with --owner-map=FILE, affects only those files whose owner is not listed in FILE. --owner-map=FILE Read owner translation map from FILE. Empty lines are ignored. Comments are introduced with # sign and extend to the end of line. Each non-empty line in FILE defines translation for a single UID. It must consist of two fields, delimited by any amount of whitespace: OLDUSR NEWUSR[:NEWUID] OLDUSR is either a valid user name or a UID prefixed with +. Unless NEWUID is supplied, NEWUSR must also be either a valid user name or a +UID. Otherwise, both NEWUSR and NEWUID need not be listed in the system user database. As a result, each input file owned by OLDUSR will be stored in archive with owner name NEWUSR and UID NEWUID. -p, --preserve-permissions, --same-permissions Set permissions of extracted files to those recorded in the archive (default for superuser). --same-owner Try extracting files with the same ownership as exists in the archive (default for superuser). -s, --preserve-order, --same-order Tell tar that the list of file names to process is sorted in the same order as the files in the archive. --sort=ORDER When creating an archive, sort directory entries according to ORDER, which is one of none, name, or inode. The default is --sort=none, which stores archive members in the same order as returned by the operating system. Using --sort=name ensures the member ordering in the created archive is uniform and reproducible. Using --sort=inode reduces the number of disk seeks made when creating the archive and thus can considerably speed up archivation. This sorting order is supported only if the underlying system provides the necessary information. Extended file attributes --acls Enable POSIX ACLs support. --no-acls Disable POSIX ACLs support. --selinux Enable SELinux context support. --no-selinux Disable SELinux context support. --xattrs Enable extended attributes support. --no-xattrs Disable extended attributes support. --xattrs-exclude=PATTERN Specify the exclude pattern for xattr keys. PATTERN is a globbing pattern, e.g. --xattrs-exclude='user.*' to include only attributes from the user namespace. --xattrs-include=PATTERN Specify the include pattern for xattr keys. PATTERN is a globbing pattern. Device selection and switching -f, --file=ARCHIVE Use archive file or device ARCHIVE. If this option is not given, tar will first examine the environment variable `TAPE'. If it is set, its value will be used as the archive name. Otherwise, tar will assume the compiled-in default. The default value can be inspected either using the --show-defaults option, or at the end of the tar --help output. An archive name that has a colon in it specifies a file or device on a remote machine. The part before the colon is taken as the machine name or IP address, and the part after it as the file or device pathname, e.g.: --file=remotehost:/dev/sr0 An optional username can be prefixed to the hostname, placing a @ sign between them. By default, the remote host is accessed via the rsh(1) command. Nowadays it is common to use ssh(1) instead. You can do so by giving the following command line option: --rsh-command=/usr/bin/ssh The remote machine should have the rmt(8) command installed. If its pathname does not match tar's default, you can inform tar about the correct pathname using the --rmt-command option. --force-local Archive file is local even if it has a colon. -F, --info-script=COMMAND, --new-volume-script=COMMAND Run COMMAND at the end of each tape (implies -M). The command can include arguments. When started, it will inherit tar's environment plus the following variables: TAR_VERSION GNU tar version number. TAR_ARCHIVE The name of the archive tar is processing. TAR_BLOCKING_FACTOR Current blocking factor, i.e. number of 512-byte blocks in a record. TAR_VOLUME Ordinal number of the volume tar is processing (set if reading a multi-volume archive). TAR_FORMAT Format of the archive being processed. One of: gnu, oldgnu, posix, ustar, v7. TAR_SUBCOMMAND A short option (with a leading dash) describing the operation tar is executing. TAR_FD File descriptor which can be used to communicate the new volume name to tar. If the info script fails, tar exits; otherwise, it begins writing the next volume. -L, --tape-length=N Change tape after writing Nx1024 bytes. If N is followed by a size suffix (see the subsection Size suffixes below), the suffix specifies the multiplicative factor to be used instead of 1024. This option implies -M. -M, --multi-volume Create/list/extract multi-volume archive. --rmt-command=COMMAND Use COMMAND instead of rmt when accessing remote archives. See the description of the -f option, above. --rsh-command=COMMAND Use COMMAND instead of rsh when accessing remote archives. See the description of the -f option, above. --volno-file=FILE When this option is used in conjunction with --multi-volume, tar will keep track of which volume of a multi-volume archive it is working in FILE. Device blocking -b, --blocking-factor=BLOCKS Set record size to BLOCKSx512 bytes. -B, --read-full-records When listing or extracting, accept incomplete input records after end-of-file marker. -i, --ignore-zeros Ignore zeroed blocks in archive. Normally two consecutive 512-blocks filled with zeroes mean EOF and tar stops reading after encountering them. This option instructs it to read further and is useful when reading archives created with the -A option. --record-size=NUMBER Set record size. NUMBER is the number of bytes per record. It must be multiple of 512. It can can be suffixed with a size suffix, e.g. --record-size=10K, for 10 Kilobytes. See the subsection Size suffixes, for a list of valid suffixes. Archive format selection -H, --format=FORMAT Create archive of the given format. Valid formats are: gnu GNU tar 1.13.x format oldgnu GNU format as per tar <= 1.12. pax, posix POSIX 1003.1-2001 (pax) format. ustar POSIX 1003.1-1988 (ustar) format. v7 Old V7 tar format. --old-archive, --portability Same as --format=v7. --pax-option=keyword[[:]=value][,keyword[[:]=value]]... Control pax keywords when creating PAX archives (-H pax). This option is equivalent to the -o option of the pax(1) utility. --posix Same as --format=posix. -V, --label=TEXT Create archive with volume name TEXT. If listing or extracting, use TEXT as a globbing pattern for volume name. Compression options -a, --auto-compress Use archive suffix to determine the compression program. -I, --use-compress-program=COMMAND Filter data through COMMAND. It must accept the -d option, for decompression. The argument can contain command line options. -j, --bzip2 Filter the archive through bzip2(1). -J, --xz Filter the archive through xz(1). --lzip Filter the archive through lzip(1). --lzma Filter the archive through lzma(1). --lzop Filter the archive through lzop(1). --no-auto-compress Do not use archive suffix to determine the compression program. -z, --gzip, --gunzip, --ungzip Filter the archive through gzip(1). -Z, --compress, --uncompress Filter the archive through compress(1). --zstd Filter the archive through zstd(1). Local file selection --add-file=FILE Add FILE to the archive (useful if its name starts with a dash). --backup[=CONTROL] Backup before removal. The CONTROL argument, if supplied, controls the backup policy. Its valid values are: none, off Never make backups. t, numbered Make numbered backups. nil, existing Make numbered backups if numbered backups exist, simple backups otherwise. never, simple Always make simple backups If CONTROL is not given, the value is taken from the VERSION_CONTROL environment variable. If it is not set, existing is assumed. -C, --directory=DIR Change to DIR before performing any operations. This option is order-sensitive, i.e. it affects all options that follow. --exclude=PATTERN Exclude files matching PATTERN, a glob(3)-style wildcard pattern. --exclude-backups Exclude backup and lock files. --exclude-caches Exclude contents of directories containing file CACHEDIR.TAG, except for the tag file itself. --exclude-caches-all Exclude directories containing file CACHEDIR.TAG and the file itself. --exclude-caches-under Exclude everything under directories containing CACHEDIR.TAG --exclude-ignore=FILE Before dumping a directory, see if it contains FILE. If so, read exclusion patterns from this file. The patterns affect only the directory itself. --exclude-ignore-recursive=FILE Same as --exclude-ignore, except that patterns from FILE affect both the directory and all its subdirectories. --exclude-tag=FILE Exclude contents of directories containing FILE, except for FILE itself. --exclude-tag-all=FILE Exclude directories containing FILE. --exclude-tag-under=FILE Exclude everything under directories containing FILE. --exclude-vcs Exclude version control system directories. --exclude-vcs-ignores Exclude files that match patterns read from VCS-specific ignore files. Supported files are: .cvsignore, .gitignore, .bzrignore, and .hgignore. -h, --dereference Follow symlinks; archive and dump the files they point to. --hard-dereference Follow hard links; archive and dump the files they refer to. -K, --starting-file=MEMBER Begin at the given member in the archive. --newer-mtime=DATE Work on files whose data changed after the DATE. If DATE starts with / or . it is taken to be a file name; the mtime of that file is used as the date. --no-null Disable the effect of the previous --null option. --no-recursion Avoid descending automatically in directories. --no-unquote Do not unquote input file or member names. --no-verbatim-files-from Treat each line read from a file list as if it were supplied in the command line. I.e., leading and trailing whitespace is removed and, if the resulting string begins with a dash, it is treated as tar command line option. This is the default behavior. The --no-verbatim-files-from option is provided as a way to restore it after --verbatim-files-from option. This option is positional: it affects all --files-from options that occur after it in, until --verbatim-files-from option or end of line, whichever occurs first. It is implied by the --no-null option. --null Instruct subsequent -T options to read null-terminated names verbatim (disables special handling of names that start with a dash). See also --verbatim-files-from. -N, --newer=DATE, --after-date=DATE Only store files newer than DATE. If DATE starts with / or . it is taken to be a file name; the mtime of that file is used as the date. --one-file-system Stay in local file system when creating archive. -P, --absolute-names Don't strip leading slashes from file names when creating archives. --recursion Recurse into directories (default). --suffix=STRING Backup before removal, override usual suffix. Default suffix is ~, unless overridden by environment variable SIMPLE_BACKUP_SUFFIX. -T, --files-from=FILE Get names to extract or create from FILE. Unless specified otherwise, the FILE must contain a list of names separated by ASCII LF (i.e. one name per line). The names read are handled the same way as command line arguments. They undergo quote removal and word splitting, and any string that starts with a - is handled as tar command line option. If this behavior is undesirable, it can be turned off using the --verbatim-files-from option. The --null option instructs tar that the names in FILE are separated by ASCII NUL character, instead of LF. It is useful if the list is generated by find(1) -print0 predicate. --unquote Unquote file or member names (default). --verbatim-files-from Treat each line obtained from a file list as a file name, even if it starts with a dash. File lists are supplied with the --files-from (-T) option. The default behavior is to handle names supplied in file lists as if they were typed in the command line, i.e. any names starting with a dash are treated as tar options. The --verbatim-files-from option disables this behavior. This option affects all --files-from options that occur after it in the command line. Its effect is reverted by the --no-verbatim-files-from option. This option is implied by the --null option. See also --add-file. -X, --exclude-from=FILE Exclude files matching patterns listed in FILE. File name transformations --strip-components=NUMBER Strip NUMBER leading components from file names on extraction. --transform=EXPRESSION, --xform=EXPRESSION Use sed replace EXPRESSION to transform file names. File name matching options These options affect both exclude and include patterns. --anchored Patterns match file name start. --ignore-case Ignore case. --no-anchored Patterns match after any / (default for exclusion). --no-ignore-case Case sensitive matching (default). --no-wildcards Verbatim string matching. --no-wildcards-match-slash Wildcards do not match /. --wildcards Use wildcards (default for exclusion). --wildcards-match-slash Wildcards match / (default for exclusion). Informative output --checkpoint[=N] Display progress messages every Nth record (default 10). --checkpoint-action=ACTION Run ACTION on each checkpoint. --clamp-mtime Only set time when the file is more recent than what was given with --mtime. --full-time Print file time to its full resolution. --index-file=FILE Send verbose output to FILE. -l, --check-links Print a message if not all links are dumped. --no-quote-chars=STRING Disable quoting for characters from STRING. --quote-chars=STRING Additionally quote characters from STRING. --quoting-style=STYLE Set quoting style for file and member names. Valid values for STYLE are literal, shell, shell-always, c, c-maybe, escape, locale, clocale. -R, --block-number Show block number within archive with each message. --show-omitted-dirs When listing or extracting, list each directory that does not match search criteria. --show-transformed-names, --show-stored-names Show file or archive names after transformation by --strip and --transform options. --totals[=SIGNAL] Print total bytes after processing the archive. If SIGNAL is given, print total bytes when this signal is delivered. Allowed signals are: SIGHUP, SIGQUIT, SIGINT, SIGUSR1, and SIGUSR2. The SIG prefix can be omitted. --utc Print file modification times in UTC. -v, --verbose Verbosely list files processed. Each instance of this option on the command line increases the verbosity level by one. The maximum verbosity level is 3. For a detailed discussion of how various verbosity levels affect tar's output, please refer to GNU Tar Manual, subsection 2.5.2 "The '--verbose' Option". --warning=KEYWORD Enable or disable warning messages identified by KEYWORD. The messages are suppressed if KEYWORD is prefixed with no- and enabled otherwise. Multiple --warning options accumulate. Keywords controlling general tar operation: all Enable all warning messages. This is the default. none Disable all warning messages. filename-with-nuls "%s: file name read contains nul character" alone-zero-block "A lone zero block at %s" Keywords applicable for tar --create: cachedir "%s: contains a cache directory tag %s; %s" file-shrank "%s: File shrank by %s bytes; padding with zeros" xdev "%s: file is on a different filesystem; not dumped" file-ignored "%s: Unknown file type; file ignored" "%s: socket ignored" "%s: door ignored" file-unchanged "%s: file is unchanged; not dumped" ignore-archive "%s: archive cannot contain itself; not dumped" file-removed "%s: File removed before we read it" file-changed "%s: file changed as we read it" failed-read Suppresses warnings about unreadable files or directories. This keyword applies only if used together with the --ignore-failed-read option. Keywords applicable for tar --extract: existing-file "%s: skipping existing file" timestamp "%s: implausibly old time stamp %s" "%s: time stamp %s is %s s in the future" contiguous-cast "Extracting contiguous files as regular files" symlink-cast "Attempting extraction of symbolic links as hard links" unknown-cast "%s: Unknown file type '%c', extracted as normal file" ignore-newer "Current %s is newer or same age" unknown-keyword "Ignoring unknown extended header keyword '%s'" decompress-program Controls verbose description of failures occurring when trying to run alternative decompressor programs. This warning is disabled by default (unless --verbose is used). A common example of what you can get when using this warning is: $ tar --warning=decompress-program -x -f archive.Z tar (child): cannot run compress: No such file or directory tar (child): trying gzip This means that tar first tried to decompress archive.Z using compress, and, when that failed, switched to gzip. record-size "Record size = %lu blocks" Keywords controlling incremental extraction: rename-directory "%s: Directory has been renamed from %s" "%s: Directory has been renamed" new-directory "%s: Directory is new" xdev "%s: directory is on a different device: not purging" bad-dumpdir "Malformed dumpdir: 'X' never used" -w, --interactive, --confirmation Ask for confirmation for every action. Compatibility options -o When creating, same as --old-archive. When extracting, same as --no-same-owner. Size suffixes Suffix Units Byte Equivalent b Blocks SIZE x 512 B Kilobytes SIZE x 1024 c Bytes SIZE G Gigabytes SIZE x 1024^3 K Kilobytes SIZE x 1024 k Kilobytes SIZE x 1024 M Megabytes SIZE x 1024^2 P Petabytes SIZE x 1024^5 T Terabytes SIZE x 1024^4 w Words SIZE x 2 RETURN VALUE top Tar's exit code indicates whether it was able to successfully perform the requested operation, and if not, what kind of error occurred. 0 Successful termination. 1 Some files differ. If tar was invoked with the --compare (--diff, -d) command line option, this means that some files in the archive differ from their disk counterparts. If tar was given one of the --create, --append or --update options, this exit code means that some files were changed while being archived and so the resulting archive does not contain the exact copy of the file set. 2 Fatal error. This means that some fatal, unrecoverable error occurred. If a subprocess that had been invoked by tar exited with a nonzero exit code, tar itself exits with that code as well. This can happen, for example, if a compression option (e.g. -z) was used and the external compressor program failed. Another example is rmt failure during backup to a remote device. SEE ALSO top bzip2(1), compress(1), gzip(1), lzma(1), lzop(1), rmt(8), symlink(7), xz(1), zstd(1). Complete tar manual: run info tar or use emacs(1) info mode to read it. Online copies of GNU tar documentation in various formats can be found at: https://www.gnu.org/software/tar/manual BUG REPORTS top Report bugs to <bug-tar@gnu.org>. COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. COLOPHON top This page is part of the tar (an archiver program) project. Information about the project can be found at http://savannah.gnu.org/projects/tar/. If you have a bug report for this manual page, see http://savannah.gnu.org/bugs/?group=tar. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/tar.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-09-12.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org TAR July 11, 2022 TAR(1) Pages that refer to this page: attr(1), dpkg-deb(1), dpkg-source(1), machinectl(1), rsync(1), st(4), suffixes(7), symlink(7), cupsd-helper(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Decompress and unarchive "hello-0.2.tar.gz" Bash Command:<START>gzip -dc hello-0.2.tar.gz | tar -xf -<END>

Decompresses each of "*bz2" files under the current folder, redirecting output to the standard out, and prints only fourth of comma-separated fields.

find . -name "*.bz2" -print0 | xargs -I{} -0 bzip2 -dc {} | cut -f, -d4

['find', 'xargs', 'cut']

Output a Bash command to accomplish the following task. Task: Decompresses each of "*bz2" files under the current folder, redirecting output to the standard out, and prints only fourth of comma-separated fields. Bash Command:<START>find . -name "*.bz2" -print0 | xargs -I{} -0 bzip2 -dc {} | cut -f, -d4<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # cut\n\n> Cut out fields from `stdin` or files.\n> More information: <https://www.gnu.org/software/coreutils/cut>.\n\n- Print a specific character/field range of each line:\n\n`{{command}} | cut --{{characters|fields}}={{1|1,10|1-10|1-|-10}}`\n\n- Print a field range of each line with a specific delimiter:\n\n`{{command}} | cut --delimiter="{{,}}" --fields={{1}}`\n\n- Print a character range of each line of the specific file:\n\n`cut --characters={{1}} {{path/to/file}}`\n Task: Decompresses each of "*bz2" files under the current folder, redirecting output to the standard out, and prints only fourth of comma-separated fields. Bash Command:<START>find . -name "*.bz2" -print0 | xargs -I{} -0 bzip2 -dc {} | cut -f, -d4<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. cut(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training cut(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON CUT(1) User Commands CUT(1) NAME top cut - remove sections from each line of files SYNOPSIS top cut OPTION... [FILE]... DESCRIPTION top Print selected parts of lines from each FILE to standard output. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -b, --bytes=LIST select only these bytes -c, --characters=LIST select only these characters -d, --delimiter=DELIM use DELIM instead of TAB for field delimiter -f, --fields=LIST select only these fields; also print any line that contains no delimiter character, unless the -s option is specified -n (ignored) --complement complement the set of selected bytes, characters or fields -s, --only-delimited do not print lines not containing delimiters --output-delimiter=STRING use STRING as the output delimiter the default is to use the input delimiter -z, --zero-terminated line delimiter is NUL, not newline --help display this help and exit --version output version information and exit Use one, and only one of -b, -c or -f. Each LIST is made up of one range, or many ranges separated by commas. Selected input is written in the same order that it is read, and is written exactly once. Each range is one of: N N'th byte, character or field, counted from 1 N- from N'th byte, character or field, to end of line N-M from N'th to M'th (included) byte, character or field -M from first to M'th (included) byte, character or field AUTHOR top Written by David M. Ihnat, David MacKenzie, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top Full documentation <https://www.gnu.org/software/coreutils/cut> or available locally via: info '(coreutils) cut invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 CUT(1) Pages that refer to this page: man-pages(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Decompresses each of "*bz2" files under the current folder, redirecting output to the standard out, and prints only fourth of comma-separated fields. Bash Command:<START>find . -name "*.bz2" -print0 | xargs -I{} -0 bzip2 -dc {} | cut -f, -d4<END>

Delete all ".DS_Store" files/directories under test directory

find test -name ".DS_Store" -delete

['find', 'test']

Output a Bash command to accomplish the following task. Task: Delete all ".DS_Store" files/directories under test directory Bash Command:<START>find test -name ".DS_Store" -delete<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # test\n\n> Check file types and compare values.\n> Returns 0 if the condition evaluates to true, 1 if it evaluates to false.\n> More information: <https://www.gnu.org/software/coreutils/test>.\n\n- Test if a given variable is equal to a given string:\n\n`test "{{$MY_VAR}}" = "{{/bin/zsh}}"`\n\n- Test if a given variable is empty:\n\n`test -z "{{$GIT_BRANCH}}"`\n\n- Test if a file exists:\n\n`test -f "{{path/to/file_or_directory}}"`\n\n- Test if a directory does not exist:\n\n`test ! -d "{{path/to/directory}}"`\n\n- If A is true, then do B, or C in the case of an error (notice that C may run even if A fails):\n\n`test {{condition}} && {{echo "true"}} || {{echo "false"}}`\n Task: Delete all ".DS_Store" files/directories under test directory Bash Command:<START>find test -name ".DS_Store" -delete<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. test(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training test(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON TEST(1) User Commands TEST(1) NAME top test - check file types and compare values SYNOPSIS top test EXPRESSION test [ EXPRESSION ] [ ] [ OPTION DESCRIPTION top Exit with the status determined by EXPRESSION. --help display this help and exit --version output version information and exit An omitted EXPRESSION defaults to false. Otherwise, EXPRESSION is true or false and sets exit status. It is one of: ( EXPRESSION ) EXPRESSION is true ! EXPRESSION EXPRESSION is false EXPRESSION1 -a EXPRESSION2 both EXPRESSION1 and EXPRESSION2 are true EXPRESSION1 -o EXPRESSION2 either EXPRESSION1 or EXPRESSION2 is true -n STRING the length of STRING is nonzero STRING equivalent to -n STRING -z STRING the length of STRING is zero STRING1 = STRING2 the strings are equal STRING1 != STRING2 the strings are not equal INTEGER1 -eq INTEGER2 INTEGER1 is equal to INTEGER2 INTEGER1 -ge INTEGER2 INTEGER1 is greater than or equal to INTEGER2 INTEGER1 -gt INTEGER2 INTEGER1 is greater than INTEGER2 INTEGER1 -le INTEGER2 INTEGER1 is less than or equal to INTEGER2 INTEGER1 -lt INTEGER2 INTEGER1 is less than INTEGER2 INTEGER1 -ne INTEGER2 INTEGER1 is not equal to INTEGER2 FILE1 -ef FILE2 FILE1 and FILE2 have the same device and inode numbers FILE1 -nt FILE2 FILE1 is newer (modification date) than FILE2 FILE1 -ot FILE2 FILE1 is older than FILE2 -b FILE FILE exists and is block special -c FILE FILE exists and is character special -d FILE FILE exists and is a directory -e FILE FILE exists -f FILE FILE exists and is a regular file -g FILE FILE exists and is set-group-ID -G FILE FILE exists and is owned by the effective group ID -h FILE FILE exists and is a symbolic link (same as -L) -k FILE FILE exists and has its sticky bit set -L FILE FILE exists and is a symbolic link (same as -h) -N FILE FILE exists and has been modified since it was last read -O FILE FILE exists and is owned by the effective user ID -p FILE FILE exists and is a named pipe -r FILE FILE exists and the user has read access -s FILE FILE exists and has a size greater than zero -S FILE FILE exists and is a socket -t FD file descriptor FD is opened on a terminal -u FILE FILE exists and its set-user-ID bit is set -w FILE FILE exists and the user has write access -x FILE FILE exists and the user has execute (or search) access Except for -h and -L, all FILE-related tests dereference symbolic links. Beware that parentheses need to be escaped (e.g., by backslashes) for shells. INTEGER may also be -l STRING, which evaluates to the length of STRING. NOTE: Binary -a and -o are inherently ambiguous. Use 'test EXPR1 && test EXPR2' or 'test EXPR1 || test EXPR2' instead. NOTE: [ honors the --help and --version options, but test does not. test treats each of those as it treats any other nonempty STRING. NOTE: your shell may have its own version of test and/or [, which usually supersedes the version described here. Please refer to your shell's documentation for details about the options it supports. AUTHOR top Written by Kevin Braunsdorf and Matthew Bradburn. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top access(2) Full documentation <https://www.gnu.org/software/coreutils/test> or available locally via: info '(coreutils) test invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 TEST(1) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all ".DS_Store" files/directories under test directory Bash Command:<START>find test -name ".DS_Store" -delete<END>

Delete all '-' character from $1 and save the resultant string to variable 'COLUMN'

COLUMN=`echo $1 | tr -d -`

['tr', 'echo']

Output a Bash command to accomplish the following task. Task: Delete all '-' character from $1 and save the resultant string to variable 'COLUMN' Bash Command:<START>COLUMN=`echo $1 | tr -d -`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # tr\n\n> Translate characters: run replacements based on single characters and character sets.\n> More information: <https://www.gnu.org/software/coreutils/tr>.\n\n- Replace all occurrences of a character in a file, and print the result:\n\n`tr {{find_character}} {{replace_character}} < {{path/to/file}}`\n\n- Replace all occurrences of a character from another command's output:\n\n`echo {{text}} | tr {{find_character}} {{replace_character}}`\n\n- Map each character of the first set to the corresponding character of the second set:\n\n`tr '{{abcd}}' '{{jkmn}}' < {{path/to/file}}`\n\n- Delete all occurrences of the specified set of characters from the input:\n\n`tr -d '{{input_characters}}' < {{path/to/file}}`\n\n- Compress a series of identical characters to a single character:\n\n`tr -s '{{input_characters}}' < {{path/to/file}}`\n\n- Translate the contents of a file to upper-case:\n\n`tr "[:lower:]" "[:upper:]" < {{path/to/file}}`\n\n- Strip out non-printable characters from a file:\n\n`tr -cd "[:print:]" < {{path/to/file}}`\n # echo\n\n> Print given arguments.\n> More information: <https://www.gnu.org/software/coreutils/echo>.\n\n- Print a text message. Note: quotes are optional:\n\n`echo "{{Hello World}}"`\n\n- Print a message with environment variables:\n\n`echo "{{My path is $PATH}}"`\n\n- Print a message without the trailing newline:\n\n`echo -n "{{Hello World}}"`\n\n- Append a message to the file:\n\n`echo "{{Hello World}}" >> {{file.txt}}`\n\n- Enable interpretation of backslash escapes (special characters):\n\n`echo -e "{{Column 1\tColumn 2}}"`\n\n- Print the exit status of the last executed command (Note: In Windows Command Prompt and PowerShell the equivalent commands are `echo %errorlevel%` and `$lastexitcode` respectively):\n\n`echo $?`\n Task: Delete all '-' character from $1 and save the resultant string to variable 'COLUMN' Bash Command:<START>COLUMN=`echo $1 | tr -d -`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: tr(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training tr(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | BUGS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON TR(1) User Commands TR(1) NAME top tr - translate or delete characters SYNOPSIS top tr [OPTION]... STRING1 [STRING2] DESCRIPTION top Translate, squeeze, and/or delete characters from standard input, writing to standard output. STRING1 and STRING2 specify arrays of characters ARRAY1 and ARRAY2 that control the action. -c, -C, --complement use the complement of ARRAY1 -d, --delete delete characters in ARRAY1, do not translate -s, --squeeze-repeats replace each sequence of a repeated character that is listed in the last specified ARRAY, with a single occurrence of that character -t, --truncate-set1 first truncate ARRAY1 to length of ARRAY2 --help display this help and exit --version output version information and exit ARRAYs are specified as strings of characters. Most represent themselves. Interpreted sequences are: \NNN character with octal value NNN (1 to 3 octal digits) \\ backslash \a audible BEL \b backspace \f form feed \n new line \r return \t horizontal tab \v vertical tab CHAR1-CHAR2 all characters from CHAR1 to CHAR2 in ascending order [CHAR*] in ARRAY2, copies of CHAR until length of ARRAY1 [CHAR*REPEAT] REPEAT copies of CHAR, REPEAT octal if starting with 0 [:alnum:] all letters and digits [:alpha:] all letters [:blank:] all horizontal whitespace [:cntrl:] all control characters [:digit:] all digits [:graph:] all printable characters, not including space [:lower:] all lower case letters [:print:] all printable characters, including space [:punct:] all punctuation characters [:space:] all horizontal or vertical whitespace [:upper:] all upper case letters [:xdigit:] all hexadecimal digits [=CHAR=] all characters which are equivalent to CHAR Translation occurs if -d is not given and both STRING1 and STRING2 appear. -t is only significant when translating. ARRAY2 is extended to length of ARRAY1 by repeating its last character as necessary. Excess characters of ARRAY2 are ignored. Character classes expand in unspecified order; while translating, [:lower:] and [:upper:] may be used in pairs to specify case conversion. Squeezing occurs after translation or deletion. BUGS top Full support is available only for safe single-byte locales, in which every possible input byte represents a single character. The C locale is safe in GNU systems, so you can avoid this issue in the shell by running LC_ALL=C tr instead of plain tr. AUTHOR top Written by Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top Full documentation <https://www.gnu.org/software/coreutils/tr> or available locally via: info '(coreutils) tr invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 TR(1) Pages that refer to this page: sed(1), proc(5) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. echo(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training echo(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON ECHO(1) User Commands ECHO(1) NAME top echo - display a line of text SYNOPSIS top echo [SHORT-OPTION]... [STRING]... echo LONG-OPTION DESCRIPTION top Echo the STRING(s) to standard output. -n do not output the trailing newline -e enable interpretation of backslash escapes -E disable interpretation of backslash escapes (default) --help display this help and exit --version output version information and exit If -e is in effect, the following sequences are recognized: \\ backslash \a alert (BEL) \b backspace \c produce no further output \e escape \f form feed \n new line \r carriage return \t horizontal tab \v vertical tab \0NNN byte with octal value NNN (1 to 3 digits) \xHH byte with hexadecimal value HH (1 to 2 digits) NOTE: your shell may have its own version of echo, which usually supersedes the version described here. Please refer to your shell's documentation for details about the options it supports. NOTE: printf(1) is a preferred alternative, which does not have issues outputting option-like strings. AUTHOR top Written by Brian Fox and Chet Ramey. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top printf(1) Full documentation <https://www.gnu.org/software/coreutils/echo> or available locally via: info '(coreutils) echo invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 ECHO(1) Pages that refer to this page: ldapcompare(1), systemd-ask-password(1), systemd-run(1), cpuset(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all '-' character from $1 and save the resultant string to variable 'COLUMN' Bash Command:<START>COLUMN=`echo $1 | tr -d -`<END>

Delete all 'restore.php' files in /var/www and 3 levels below

find /var/www -maxdepth 4 -name 'restore.php' -exec rm -r {} \;

['find', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all 'restore.php' files in /var/www and 3 levels below Bash Command:<START>find /var/www -maxdepth 4 -name 'restore.php' -exec rm -r {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all 'restore.php' files in /var/www and 3 levels below Bash Command:<START>find /var/www -maxdepth 4 -name 'restore.php' -exec rm -r {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all 'restore.php' files in /var/www and 3 levels below Bash Command:<START>find /var/www -maxdepth 4 -name 'restore.php' -exec rm -r {} \;<END>

Delete all *.zip files under current directory that are older than 2 days

find . -name "*.zip" -mtime +2 -print0 | xargs -0 -I {} rm {}

['find', 'xargs', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all *.zip files under current directory that are older than 2 days Bash Command:<START>find . -name "*.zip" -mtime +2 -print0 | xargs -0 -I {} rm {}<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all *.zip files under current directory that are older than 2 days Bash Command:<START>find . -name "*.zip" -mtime +2 -print0 | xargs -0 -I {} rm {}<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all *.zip files under current directory that are older than 2 days Bash Command:<START>find . -name "*.zip" -mtime +2 -print0 | xargs -0 -I {} rm {}<END>

Delete all *.zip files under current directory that are older than 2 days

find . -name "*.zip" -mtime +2 orint0 | xargs -0 rm

['find', 'xargs', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all *.zip files under current directory that are older than 2 days Bash Command:<START>find . -name "*.zip" -mtime +2 orint0 | xargs -0 rm<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all *.zip files under current directory that are older than 2 days Bash Command:<START>find . -name "*.zip" -mtime +2 orint0 | xargs -0 rm<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all *.zip files under current directory that are older than 2 days Bash Command:<START>find . -name "*.zip" -mtime +2 orint0 | xargs -0 rm<END>

Delete all *txt files under current directory

find . -name "*txt" -type f -print | xargs rm

['find', 'xargs', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all *txt files under current directory Bash Command:<START>find . -name "*txt" -type f -print | xargs rm<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all *txt files under current directory Bash Command:<START>find . -name "*txt" -type f -print | xargs rm<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all *txt files under current directory Bash Command:<START>find . -name "*txt" -type f -print | xargs rm<END>

Delete all .bam files in the current directory tree

find . -name "*.bam" | xargs rm

['find', 'xargs', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all .bam files in the current directory tree Bash Command:<START>find . -name "*.bam" | xargs rm<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all .bam files in the current directory tree Bash Command:<START>find . -name "*.bam" | xargs rm<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all .bam files in the current directory tree Bash Command:<START>find . -name "*.bam" | xargs rm<END>

Delete all .pyc files in the current directory tree

find . -name "*.pyc" | xargs -0 rm -rf

['find', 'xargs', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all .pyc files in the current directory tree Bash Command:<START>find . -name "*.pyc" | xargs -0 rm -rf<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all .pyc files in the current directory tree Bash Command:<START>find . -name "*.pyc" | xargs -0 rm -rf<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all .pyc files in the current directory tree Bash Command:<START>find . -name "*.pyc" | xargs -0 rm -rf<END>

Delete all .pyc files in the current directory tree

find . -name "*.pyc" | xargs rm -rf

['find', 'xargs', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all .pyc files in the current directory tree Bash Command:<START>find . -name "*.pyc" | xargs rm -rf<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all .pyc files in the current directory tree Bash Command:<START>find . -name "*.pyc" | xargs rm -rf<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all .pyc files in the current directory tree Bash Command:<START>find . -name "*.pyc" | xargs rm -rf<END>

Delete all .svn directories under current directory

find . -type d -name .svn -print0|xargs -0 rm -rf

['find', 'xargs', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all .svn directories under current directory Bash Command:<START>find . -type d -name .svn -print0|xargs -0 rm -rf<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all .svn directories under current directory Bash Command:<START>find . -type d -name .svn -print0|xargs -0 rm -rf<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all .svn directories under current directory Bash Command:<START>find . -type d -name .svn -print0|xargs -0 rm -rf<END>

Delete all .svn files/directories under current directory

find . -depth -name .svn -exec rm -fr {} \;

['find', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -depth -name .svn -exec rm -fr {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -depth -name .svn -exec rm -fr {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -depth -name .svn -exec rm -fr {} \;<END>

Delete all .svn files/directories under current directory

find . -name .svn -delete

['find']

Output a Bash command to accomplish the following task. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -delete<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -delete<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -delete<END>

Delete all .svn files/directories under current directory

find . -name .svn -exec rm -rf '{}' \;

['find', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -exec rm -rf '{}' \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -exec rm -rf '{}' \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -exec rm -rf '{}' \;<END>

Delete all .svn files/directories under current directory

find . -name .svn -exec rm -rf {} +

['find', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -exec rm -rf {} +<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -exec rm -rf {} +<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -exec rm -rf {} +<END>

Delete all .svn files/directories under current directory

find . -name .svn -exec rm -rf {} \;

['find', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -exec rm -rf {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -exec rm -rf {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -exec rm -rf {} \;<END>

Delete all .svn files/directories under current directory

find . -name .svn -exec rm -v {} \;

['find', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -exec rm -v {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -exec rm -v {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn -exec rm -v {} \;<END>

Delete all .svn files/directories under current directory

find . -name .svn | xargs rm -fr

['find', 'xargs', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn | xargs rm -fr<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn | xargs rm -fr<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn | xargs rm -fr<END>

Delete all .svn files/directories under current directory

find . -name .svn |xargs rm -rf

['find', 'xargs', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn |xargs rm -rf<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn |xargs rm -rf<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all .svn files/directories under current directory Bash Command:<START>find . -name .svn |xargs rm -rf<END>

Delete all .svn subdirectories under current directory

rm -rf `find . -type d -name ".svn"`

['find', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all .svn subdirectories under current directory Bash Command:<START>rm -rf `find . -type d -name ".svn"`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all .svn subdirectories under current directory Bash Command:<START>rm -rf `find . -type d -name ".svn"`<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all .svn subdirectories under current directory Bash Command:<START>rm -rf `find . -type d -name ".svn"`<END>

Delete all 1US* (case insensitive) files under current directory

find . -iname "1US*" -exec rm {} \;

['find', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all 1US* (case insensitive) files under current directory Bash Command:<START>find . -iname "1US*" -exec rm {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all 1US* (case insensitive) files under current directory Bash Command:<START>find . -iname "1US*" -exec rm {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all 1US* (case insensitive) files under current directory Bash Command:<START>find . -iname "1US*" -exec rm {} \;<END>

Delete all HTML files under tree ~/mydir

find ~/mydir -iname '*.htm' -exec rm {} \;

['find', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all HTML files under tree ~/mydir Bash Command:<START>find ~/mydir -iname '*.htm' -exec rm {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all HTML files under tree ~/mydir Bash Command:<START>find ~/mydir -iname '*.htm' -exec rm {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all HTML files under tree ~/mydir Bash Command:<START>find ~/mydir -iname '*.htm' -exec rm {} \;<END>

Delete all MP3 files under /tmp

find /tmp -iname '*.mp3' -print0 | xargs -0 rm

['find', 'xargs', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all MP3 files under /tmp Bash Command:<START>find /tmp -iname '*.mp3' -print0 | xargs -0 rm<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all MP3 files under /tmp Bash Command:<START>find /tmp -iname '*.mp3' -print0 | xargs -0 rm<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all MP3 files under /tmp Bash Command:<START>find /tmp -iname '*.mp3' -print0 | xargs -0 rm<END>

Delete all __temp__* directories under maximum 1 level down the current directory tree

find . -maxdepth 1 -type d -name '__temp__*' -print0 | xargs -0 rm -rf

['find', 'xargs', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all __temp__* directories under maximum 1 level down the current directory tree Bash Command:<START>find . -maxdepth 1 -type d -name '__temp__*' -print0 | xargs -0 rm -rf<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all __temp__* directories under maximum 1 level down the current directory tree Bash Command:<START>find . -maxdepth 1 -type d -name '__temp__*' -print0 | xargs -0 rm -rf<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all __temp__* directories under maximum 1 level down the current directory tree Bash Command:<START>find . -maxdepth 1 -type d -name '__temp__*' -print0 | xargs -0 rm -rf<END>

Delete all __temp__* files/directories under current directory tree

find . -depth -name '__temp__*' -exec rm -rf '{}' \;

['find', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all __temp__* files/directories under current directory tree Bash Command:<START>find . -depth -name '__temp__*' -exec rm -rf '{}' \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all __temp__* files/directories under current directory tree Bash Command:<START>find . -depth -name '__temp__*' -exec rm -rf '{}' \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all __temp__* files/directories under current directory tree Bash Command:<START>find . -depth -name '__temp__*' -exec rm -rf '{}' \;<END>

Delete all __temp__* files/directories under current directory tree

find . -name __temp__* -exec rm -rf '{}' \;

['find', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all __temp__* files/directories under current directory tree Bash Command:<START>find . -name __temp__* -exec rm -rf '{}' \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all __temp__* files/directories under current directory tree Bash Command:<START>find . -name __temp__* -exec rm -rf '{}' \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all __temp__* files/directories under current directory tree Bash Command:<START>find . -name __temp__* -exec rm -rf '{}' \;<END>

Delete all broken symbolic links under '/usr/ports/packages' directory tree

find -L /usr/ports/packages -type l -exec rm -- {} +

['find', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all broken symbolic links under '/usr/ports/packages' directory tree Bash Command:<START>find -L /usr/ports/packages -type l -exec rm -- {} +<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all broken symbolic links under '/usr/ports/packages' directory tree Bash Command:<START>find -L /usr/ports/packages -type l -exec rm -- {} +<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all broken symbolic links under '/usr/ports/packages' directory tree Bash Command:<START>find -L /usr/ports/packages -type l -exec rm -- {} +<END>

Delete all but the most recent 5 files

ls -tr | head -n -5 | xargs rm

['ls', 'head', 'xargs', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all but the most recent 5 files Bash Command:<START>ls -tr | head -n -5 | xargs rm<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # ls\n\n> List directory contents.\n> More information: <https://www.gnu.org/software/coreutils/ls>.\n\n- List files one per line:\n\n`ls -1`\n\n- List all files, including hidden files:\n\n`ls -a`\n\n- List all files, with trailing `/` added to directory names:\n\n`ls -F`\n\n- Long format list (permissions, ownership, size, and modification date) of all files:\n\n`ls -la`\n\n- Long format list with size displayed using human-readable units (KiB, MiB, GiB):\n\n`ls -lh`\n\n- Long format list sorted by size (descending) recursively:\n\n`ls -lSR`\n\n- Long format list of all files, sorted by modification date (oldest first):\n\n`ls -ltr`\n\n- Only list directories:\n\n`ls -d */`\n # head\n\n> Output the first part of files.\n> More information: <https://www.gnu.org/software/coreutils/head>.\n\n- Output the first few lines of a file:\n\n`head --lines {{count}} {{path/to/file}}`\n\n- Output the first few bytes of a file:\n\n`head --bytes {{count}} {{path/to/file}}`\n\n- Output everything but the last few lines of a file:\n\n`head --lines -{{count}} {{path/to/file}}`\n\n- Output everything but the last few bytes of a file:\n\n`head --bytes -{{count}} {{path/to/file}}`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all but the most recent 5 files Bash Command:<START>ls -tr | head -n -5 | xargs rm<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: ls(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training ls(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON LS(1) User Commands LS(1) NAME top ls - list directory contents SYNOPSIS top ls [OPTION]... [FILE]... DESCRIPTION top List information about the FILEs (the current directory by default). Sort entries alphabetically if none of -cftuvSUX nor --sort is specified. Mandatory arguments to long options are mandatory for short options too. -a, --all do not ignore entries starting with . -A, --almost-all do not list implied . and .. --author with -l, print the author of each file -b, --escape print C-style escapes for nongraphic characters --block-size=SIZE with -l, scale sizes by SIZE when printing them; e.g., '--block-size=M'; see SIZE format below -B, --ignore-backups do not list implied entries ending with ~ -c with -lt: sort by, and show, ctime (time of last change of file status information); with -l: show ctime and sort by name; otherwise: sort by ctime, newest first -C list entries by columns --color[=WHEN] color the output WHEN; more info below -d, --directory list directories themselves, not their contents -D, --dired generate output designed for Emacs' dired mode -f list all entries in directory order -F, --classify[=WHEN] append indicator (one of */=>@|) to entries WHEN --file-type likewise, except do not append '*' --format=WORD across -x, commas -m, horizontal -x, long -l, single-column -1, verbose -l, vertical -C --full-time like -l --time-style=full-iso -g like -l, but do not list owner --group-directories-first group directories before files; can be augmented with a --sort option, but any use of --sort=none (-U) disables grouping -G, --no-group in a long listing, don't print group names -h, --human-readable with -l and -s, print sizes like 1K 234M 2G etc. --si likewise, but use powers of 1000 not 1024 -H, --dereference-command-line follow symbolic links listed on the command line --dereference-command-line-symlink-to-dir follow each command line symbolic link that points to a directory --hide=PATTERN do not list implied entries matching shell PATTERN (overridden by -a or -A) --hyperlink[=WHEN] hyperlink file names WHEN --indicator-style=WORD append indicator with style WORD to entry names: none (default), slash (-p), file-type (--file-type), classify (-F) -i, --inode print the index number of each file -I, --ignore=PATTERN do not list implied entries matching shell PATTERN -k, --kibibytes default to 1024-byte blocks for file system usage; used only with -s and per directory totals -l use a long listing format -L, --dereference when showing file information for a symbolic link, show information for the file the link references rather than for the link itself -m fill width with a comma separated list of entries -n, --numeric-uid-gid like -l, but list numeric user and group IDs -N, --literal print entry names without quoting -o like -l, but do not list group information -p, --indicator-style=slash append / indicator to directories -q, --hide-control-chars print ? instead of nongraphic characters --show-control-chars show nongraphic characters as-is (the default, unless program is 'ls' and output is a terminal) -Q, --quote-name enclose entry names in double quotes --quoting-style=WORD use quoting style WORD for entry names: literal, locale, shell, shell-always, shell-escape, shell-escape-always, c, escape (overrides QUOTING_STYLE environment variable) -r, --reverse reverse order while sorting -R, --recursive list subdirectories recursively -s, --size print the allocated size of each file, in blocks -S sort by file size, largest first --sort=WORD sort by WORD instead of name: none (-U), size (-S), time (-t), version (-v), extension (-X), width --time=WORD select which timestamp used to display or sort; access time (-u): atime, access, use; metadata change time (-c): ctime, status; modified time (default): mtime, modification; birth time: birth, creation; with -l, WORD determines which time to show; with --sort=time, sort by WORD (newest first) --time-style=TIME_STYLE time/date format with -l; see TIME_STYLE below -t sort by time, newest first; see --time -T, --tabsize=COLS assume tab stops at each COLS instead of 8 -u with -lt: sort by, and show, access time; with -l: show access time and sort by name; otherwise: sort by access time, newest first -U do not sort; list entries in directory order -v natural sort of (version) numbers within text -w, --width=COLS set output width to COLS. 0 means no limit -x list entries by lines instead of by columns -X sort alphabetically by entry extension -Z, --context print any security context of each file --zero end each output line with NUL, not newline -1 list one file per line --help display this help and exit --version output version information and exit The SIZE argument is an integer and optional unit (example: 10K is 10*1024). Units are K,M,G,T,P,E,Z,Y,R,Q (powers of 1024) or KB,MB,... (powers of 1000). Binary prefixes can be used, too: KiB=K, MiB=M, and so on. The TIME_STYLE argument can be full-iso, long-iso, iso, locale, or +FORMAT. FORMAT is interpreted like in date(1). If FORMAT is FORMAT1<newline>FORMAT2, then FORMAT1 applies to non-recent files and FORMAT2 to recent files. TIME_STYLE prefixed with 'posix-' takes effect only outside the POSIX locale. Also the TIME_STYLE environment variable sets the default style to use. The WHEN argument defaults to 'always' and can also be 'auto' or 'never'. Using color to distinguish file types is disabled both by default and with --color=never. With --color=auto, ls emits color codes only when standard output is connected to a terminal. The LS_COLORS environment variable can change the settings. Use the dircolors(1) command to set it. Exit status: 0 if OK, 1 if minor problems (e.g., cannot access subdirectory), 2 if serious trouble (e.g., cannot access command-line argument). AUTHOR top Written by Richard M. Stallman and David MacKenzie. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top dircolors(1) Full documentation <https://www.gnu.org/software/coreutils/ls> or available locally via: info '(coreutils) ls invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 LS(1) Pages that refer to this page: column(1), find(1), namei(1), stat(2), statx(2), glob(3), strverscmp(3), core(5), dir_colors(5), passwd(5), proc(5), mq_overview(7), symlink(7), lsblk(8), lsof(8), setfiles(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. head(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training head(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON HEAD(1) User Commands HEAD(1) NAME top head - output the first part of files SYNOPSIS top head [OPTION]... [FILE]... DESCRIPTION top Print the first 10 lines of each FILE to standard output. With more than one FILE, precede each with a header giving the file name. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -c, --bytes=[-]NUM print the first NUM bytes of each file; with the leading '-', print all but the last NUM bytes of each file -n, --lines=[-]NUM print the first NUM lines instead of the first 10; with the leading '-', print all but the last NUM lines of each file -q, --quiet, --silent never print headers giving file names -v, --verbose always print headers giving file names -z, --zero-terminated line delimiter is NUL, not newline --help display this help and exit --version output version information and exit NUM may have a multiplier suffix: b 512, kB 1000, K 1024, MB 1000*1000, M 1024*1024, GB 1000*1000*1000, G 1024*1024*1024, and so on for T, P, E, Z, Y, R, Q. Binary prefixes can be used, too: KiB=K, MiB=M, and so on. AUTHOR top Written by David MacKenzie and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top tail(1) Full documentation <https://www.gnu.org/software/coreutils/head> or available locally via: info '(coreutils) head invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 HEAD(1) Pages that refer to this page: tail(1) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all but the most recent 5 files Bash Command:<START>ls -tr | head -n -5 | xargs rm<END>

Delete all contents form the files that contain the case insensitive regex 'stringtofind' in maximum 1 level down the / directory excluding other partitions

find / -maxdepth 1 -xdev -type f -exec grep -i "stringtofind" -l {} \; -exec sed -i '/./d' {} \;

['find', 'grep', 'sed']

Output a Bash command to accomplish the following task. Task: Delete all contents form the files that contain the case insensitive regex 'stringtofind' in maximum 1 level down the / directory excluding other partitions Bash Command:<START>find / -maxdepth 1 -xdev -type f -exec grep -i "stringtofind" -l {} \; -exec sed -i '/./d' {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # grep\n\n> Find patterns in files using regular expressions.\n> More information: <https://www.gnu.org/software/grep/manual/grep.html>.\n\n- Search for a pattern within a file:\n\n`grep "{{search_pattern}}" {{path/to/file}}`\n\n- Search for an exact string (disables regular expressions):\n\n`grep --fixed-strings "{{exact_string}}" {{path/to/file}}`\n\n- Search for a pattern in all files recursively in a directory, showing line numbers of matches, ignoring binary files:\n\n`grep --recursive --line-number --binary-files={{without-match}} "{{search_pattern}}" {{path/to/directory}}`\n\n- Use extended regular expressions (supports `?`, `+`, `{}`, `()` and `|`), in case-insensitive mode:\n\n`grep --extended-regexp --ignore-case "{{search_pattern}}" {{path/to/file}}`\n\n- Print 3 lines of context around, before, or after each match:\n\n`grep --{{context|before-context|after-context}}={{3}} "{{search_pattern}}" {{path/to/file}}`\n\n- Print file name and line number for each match with color output:\n\n`grep --with-filename --line-number --color=always "{{search_pattern}}" {{path/to/file}}`\n\n- Search for lines matching a pattern, printing only the matched text:\n\n`grep --only-matching "{{search_pattern}}" {{path/to/file}}`\n\n- Search `stdin` for lines that do not match a pattern:\n\n`cat {{path/to/file}} | grep --invert-match "{{search_pattern}}"`\n # sed\n\n> Edit text in a scriptable manner.\n> See also: `awk`, `ed`.\n> More information: <https://www.gnu.org/software/sed/manual/sed.html>.\n\n- Replace all `apple` (basic regex) occurrences with `mango` (basic regex) in all input lines and print the result to `stdout`:\n\n`{{command}} | sed 's/apple/mango/g'`\n\n- Replace all `apple` (extended regex) occurrences with `APPLE` (extended regex) in all input lines and print the result to `stdout`:\n\n`{{command}} | sed -E 's/(apple)/\U\1/g'`\n\n- Replace all `apple` (basic regex) occurrences with `mango` (basic regex) in a specific file and overwrite the original file in place:\n\n`sed -i 's/apple/mango/g' {{path/to/file}}`\n\n- Execute a specific script [f]ile and print the result to `stdout`:\n\n`{{command}} | sed -f {{path/to/script.sed}}`\n\n- Print just the first line to `stdout`:\n\n`{{command}} | sed -n '1p'`\n\n- [d]elete the first line of a file:\n\n`sed -i 1d {{path/to/file}}`\n\n- [i]nsert a new line at the first line of a file:\n\n`sed -i '1i\your new line text\' {{path/to/file}}`\n Task: Delete all contents form the files that contain the case insensitive regex 'stringtofind' in maximum 1 level down the / directory excluding other partitions Bash Command:<START>find / -maxdepth 1 -xdev -type f -exec grep -i "stringtofind" -l {} \; -exec sed -i '/./d' {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. grep(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training grep(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | REGULAR EXPRESSIONS | EXIT STATUS | ENVIRONMENT | NOTES | COPYRIGHT | BUGS | EXAMPLE | SEE ALSO | COLOPHON GREP(1) User Commands GREP(1) NAME top grep - print lines that match patterns SYNOPSIS top grep [OPTION...] PATTERNS [FILE...] grep [OPTION...] -e PATTERNS ... [FILE...] grep [OPTION...] -f PATTERN_FILE ... [FILE...] DESCRIPTION top grep searches for PATTERNS in each FILE. PATTERNS is one or more patterns separated by newline characters, and grep prints each line that matches a pattern. Typically PATTERNS should be quoted when grep is used in a shell command. A FILE of - stands for standard input. If no FILE is given, recursive searches examine the working directory, and nonrecursive searches read standard input. OPTIONS top Generic Program Information --help Output a usage message and exit. -V, --version Output the version number of grep and exit. Pattern Syntax -E, --extended-regexp Interpret PATTERNS as extended regular expressions (EREs, see below). -F, --fixed-strings Interpret PATTERNS as fixed strings, not regular expressions. -G, --basic-regexp Interpret PATTERNS as basic regular expressions (BREs, see below). This is the default. -P, --perl-regexp Interpret PATTERNS as Perl-compatible regular expressions (PCREs). This option is experimental when combined with the -z (--null-data) option, and grep -P may warn of unimplemented features. Matching Control -e PATTERNS, --regexp=PATTERNS Use PATTERNS as the patterns. If this option is used multiple times or is combined with the -f (--file) option, search for all patterns given. This option can be used to protect a pattern beginning with -. -f FILE, --file=FILE Obtain patterns from FILE, one per line. If this option is used multiple times or is combined with the -e (--regexp) option, search for all patterns given. The empty file contains zero patterns, and therefore matches nothing. If FILE is - , read patterns from standard input. -i, --ignore-case Ignore case distinctions in patterns and input data, so that characters that differ only in case match each other. --no-ignore-case Do not ignore case distinctions in patterns and input data. This is the default. This option is useful for passing to shell scripts that already use -i, to cancel its effects because the two options override each other. -v, --invert-match Invert the sense of matching, to select non-matching lines. -w, --word-regexp Select only those lines containing matches that form whole words. The test is that the matching substring must either be at the beginning of the line, or preceded by a non-word constituent character. Similarly, it must be either at the end of the line or followed by a non-word constituent character. Word-constituent characters are letters, digits, and the underscore. This option has no effect if -x is also specified. -x, --line-regexp Select only those matches that exactly match the whole line. For a regular expression pattern, this is like parenthesizing the pattern and then surrounding it with ^ and $. General Output Control -c, --count Suppress normal output; instead print a count of matching lines for each input file. With the -v, --invert-match option (see above), count non-matching lines. --color[=WHEN], --colour[=WHEN] Surround the matched (non-empty) strings, matching lines, context lines, file names, line numbers, byte offsets, and separators (for fields and groups of context lines) with escape sequences to display them in color on the terminal. The colors are defined by the environment variable GREP_COLORS. WHEN is never, always, or auto. -L, --files-without-match Suppress normal output; instead print the name of each input file from which no output would normally have been printed. -l, --files-with-matches Suppress normal output; instead print the name of each input file from which output would normally have been printed. Scanning each input file stops upon first match. -m NUM, --max-count=NUM Stop reading a file after NUM matching lines. If NUM is zero, grep stops right away without reading input. A NUM of -1 is treated as infinity and grep does not stop; this is the default. If the input is standard input from a regular file, and NUM matching lines are output, grep ensures that the standard input is positioned to just after the last matching line before exiting, regardless of the presence of trailing context lines. This enables a calling process to resume a search. When grep stops after NUM matching lines, it outputs any trailing context lines. When the -c or --count option is also used, grep does not output a count greater than NUM. When the -v or --invert-match option is also used, grep stops after outputting NUM non-matching lines. -o, --only-matching Print only the matched (non-empty) parts of a matching line, with each such part on a separate output line. -q, --quiet, --silent Quiet; do not write anything to standard output. Exit immediately with zero status if any match is found, even if an error was detected. Also see the -s or --no-messages option. -s, --no-messages Suppress error messages about nonexistent or unreadable files. Output Line Prefix Control -b, --byte-offset Print the 0-based byte offset within the input file before each line of output. If -o (--only-matching) is specified, print the offset of the matching part itself. -H, --with-filename Print the file name for each match. This is the default when there is more than one file to search. This is a GNU extension. -h, --no-filename Suppress the prefixing of file names on output. This is the default when there is only one file (or only standard input) to search. --label=LABEL Display input actually coming from standard input as input coming from file LABEL. This can be useful for commands that transform a file's contents before searching, e.g., gzip -cd foo.gz | grep --label=foo -H 'some pattern'. See also the -H option. -n, --line-number Prefix each line of output with the 1-based line number within its input file. -T, --initial-tab Make sure that the first character of actual line content lies on a tab stop, so that the alignment of tabs looks normal. This is useful with options that prefix their output to the actual content: -H,-n, and -b. In order to improve the probability that lines from a single file will all start at the same column, this also causes the line number and byte offset (if present) to be printed in a minimum size field width. -Z, --null Output a zero byte (the ASCII NUL character) instead of the character that normally follows a file name. For example, grep -lZ outputs a zero byte after each file name instead of the usual newline. This option makes the output unambiguous, even in the presence of file names containing unusual characters like newlines. This option can be used with commands like find -print0, perl -0, sort -z, and xargs -0 to process arbitrary file names, even those that contain newline characters. Context Line Control -A NUM, --after-context=NUM Print NUM lines of trailing context after matching lines. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. -B NUM, --before-context=NUM Print NUM lines of leading context before matching lines. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. -C NUM, -NUM, --context=NUM Print NUM lines of output context. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. --group-separator=SEP When -A, -B, or -C are in use, print SEP instead of -- between groups of lines. --no-group-separator When -A, -B, or -C are in use, do not print a separator between groups of lines. File and Directory Selection -a, --text Process a binary file as if it were text; this is equivalent to the --binary-files=text option. --binary-files=TYPE If a file's data or metadata indicate that the file contains binary data, assume that the file is of type TYPE. Non-text bytes indicate binary data; these are either output bytes that are improperly encoded for the current locale, or null input bytes when the -z option is not given. By default, TYPE is binary, and grep suppresses output after null input binary data is discovered, and suppresses output lines that contain improperly encoded data. When some output is suppressed, grep follows any output with a message to standard error saying that a binary file matches. If TYPE is without-match, when grep discovers null input binary data it assumes that the rest of the file does not match; this is equivalent to the -I option. If TYPE is text, grep processes a binary file as if it were text; this is equivalent to the -a option. When type is binary, grep may treat non-text bytes as line terminators even without the -z option. This means choosing binary versus text can affect whether a pattern matches a file. For example, when type is binary the pattern q$ might match q immediately followed by a null byte, even though this is not matched when type is text. Conversely, when type is binary the pattern . (period) might not match a null byte. Warning: The -a option might output binary garbage, which can have nasty side effects if the output is a terminal and if the terminal driver interprets some of it as commands. On the other hand, when reading files whose text encodings are unknown, it can be helpful to use -a or to set LC_ALL='C' in the environment, in order to find more matches even if the matches are unsafe for direct display. -D ACTION, --devices=ACTION If an input file is a device, FIFO or socket, use ACTION to process it. By default, ACTION is read, which means that devices are read just as if they were ordinary files. If ACTION is skip, devices are silently skipped. -d ACTION, --directories=ACTION If an input file is a directory, use ACTION to process it. By default, ACTION is read, i.e., read directories just as if they were ordinary files. If ACTION is skip, silently skip directories. If ACTION is recurse, read all files under each directory, recursively, following symbolic links only if they are on the command line. This is equivalent to the -r option. --exclude=GLOB Skip any command-line file with a name suffix that matches the pattern GLOB, using wildcard matching; a name suffix is either the whole name, or a trailing part that starts with a non-slash character immediately after a slash (/) in the name. When searching recursively, skip any subfile whose base name matches GLOB; the base name is the part after the last slash. A pattern can use *, ?, and [...] as wildcards, and \ to quote a wildcard or backslash character literally. --exclude-from=FILE Skip files whose base name matches any of the file-name globs read from FILE (using wildcard matching as described under --exclude). --exclude-dir=GLOB Skip any command-line directory with a name suffix that matches the pattern GLOB. When searching recursively, skip any subdirectory whose base name matches GLOB. Ignore any redundant trailing slashes in GLOB. -I Process a binary file as if it did not contain matching data; this is equivalent to the --binary-files=without-match option. --include=GLOB Search only files whose base name matches GLOB (using wildcard matching as described under --exclude). If contradictory --include and --exclude options are given, the last matching one wins. If no --include or --exclude options match, a file is included unless the first such option is --include. -r, --recursive Read all files under each directory, recursively, following symbolic links only if they are on the command line. Note that if no file operand is given, grep searches the working directory. This is equivalent to the -d recurse option. -R, --dereference-recursive Read all files under each directory, recursively. Follow all symbolic links, unlike -r. Other Options --line-buffered Use line buffering on output. This can cause a performance penalty. -U, --binary Treat the file(s) as binary. By default, under MS-DOS and MS-Windows, grep guesses whether a file is text or binary as described for the --binary-files option. If grep decides the file is a text file, it strips the CR characters from the original file contents (to make regular expressions with ^ and $ work correctly). Specifying -U overrules this guesswork, causing all files to be read and passed to the matching mechanism verbatim; if the file is a text file with CR/LF pairs at the end of each line, this will cause some regular expressions to fail. This option has no effect on platforms other than MS-DOS and MS-Windows. -z, --null-data Treat input and output data as sequences of lines, each terminated by a zero byte (the ASCII NUL character) instead of a newline. Like the -Z or --null option, this option can be used with commands like sort -z to process arbitrary file names. REGULAR EXPRESSIONS top A regular expression is a pattern that describes a set of strings. Regular expressions are constructed analogously to arithmetic expressions, by using various operators to combine smaller expressions. grep understands three different versions of regular expression syntax: basic (BRE), extended (ERE) and perl (PCRE). In GNU grep, basic and extended regular expressions are merely different notations for the same pattern-matching functionality. In other implementations, basic regular expressions are ordinarily less powerful than extended, though occasionally it is the other way around. The following description applies to extended regular expressions; differences for basic regular expressions are summarized afterwards. Perl-compatible regular expressions have different functionality, and are documented in pcre2syntax(3) and pcre2pattern(3), but work only if PCRE support is enabled. The fundamental building blocks are the regular expressions that match a single character. Most characters, including all letters and digits, are regular expressions that match themselves. Any meta-character with special meaning may be quoted by preceding it with a backslash. The period . matches any single character. It is unspecified whether it matches an encoding error. Character Classes and Bracket Expressions A bracket expression is a list of characters enclosed by [ and ]. It matches any single character in that list. If the first character of the list is the caret ^ then it matches any character not in the list; it is unspecified whether it matches an encoding error. For example, the regular expression [0123456789] matches any single digit. Within a bracket expression, a range expression consists of two characters separated by a hyphen. It matches any single character that sorts between the two characters, inclusive, using the locale's collating sequence and character set. For example, in the default C locale, [a-d] is equivalent to [abcd]. Many locales sort characters in dictionary order, and in these locales [a-d] is typically not equivalent to [abcd]; it might be equivalent to [aBbCcDd], for example. To obtain the traditional interpretation of bracket expressions, you can use the C locale by setting the LC_ALL environment variable to the value C. Finally, certain named classes of characters are predefined within bracket expressions, as follows. Their names are self explanatory, and they are [:alnum:], [:alpha:], [:blank:], [:cntrl:], [:digit:], [:graph:], [:lower:], [:print:], [:punct:], [:space:], [:upper:], and [:xdigit:]. For example, [[:alnum:]] means the character class of numbers and letters in the current locale. In the C locale and ASCII character set encoding, this is the same as [0-9A-Za-z]. (Note that the brackets in these class names are part of the symbolic names, and must be included in addition to the brackets delimiting the bracket expression.) Most meta-characters lose their special meaning inside bracket expressions. To include a literal ] place it first in the list. Similarly, to include a literal ^ place it anywhere but first. Finally, to include a literal - place it last. Anchoring The caret ^ and the dollar sign $ are meta-characters that respectively match the empty string at the beginning and end of a line. The Backslash Character and Special Expressions The symbols \< and \> respectively match the empty string at the beginning and end of a word. The symbol \b matches the empty string at the edge of a word, and \B matches the empty string provided it's not at the edge of a word. The symbol \w is a synonym for [_[:alnum:]] and \W is a synonym for [^_[:alnum:]]. Repetition A regular expression may be followed by one of several repetition operators: ? The preceding item is optional and matched at most once. * The preceding item will be matched zero or more times. + The preceding item will be matched one or more times. {n} The preceding item is matched exactly n times. {n,} The preceding item is matched n or more times. {,m} The preceding item is matched at most m times. This is a GNU extension. {n,m} The preceding item is matched at least n times, but not more than m times. Concatenation Two regular expressions may be concatenated; the resulting regular expression matches any string formed by concatenating two substrings that respectively match the concatenated expressions. Alternation Two regular expressions may be joined by the infix operator |; the resulting regular expression matches any string matching either alternate expression. Precedence Repetition takes precedence over concatenation, which in turn takes precedence over alternation. A whole expression may be enclosed in parentheses to override these precedence rules and form a subexpression. Back-references and Subexpressions The back-reference \n, where n is a single digit, matches the substring previously matched by the nth parenthesized subexpression of the regular expression. Basic vs Extended Regular Expressions In basic regular expressions the meta-characters ?, +, {, |, (, and ) lose their special meaning; instead use the backslashed versions \?, \+, \{, \|, \(, and \). EXIT STATUS top Normally the exit status is 0 if a line is selected, 1 if no lines were selected, and 2 if an error occurred. However, if the -q or --quiet or --silent is used and a line is selected, the exit status is 0 even if an error occurred. ENVIRONMENT top The behavior of grep is affected by the following environment variables. The locale for category LC_foo is specified by examining the three environment variables LC_ALL, LC_foo, LANG, in that order. The first of these variables that is set specifies the locale. For example, if LC_ALL is not set, but LC_MESSAGES is set to pt_BR, then the Brazilian Portuguese locale is used for the LC_MESSAGES category. The C locale is used if none of these environment variables are set, if the locale catalog is not installed, or if grep was not compiled with national language support (NLS). The shell command locale -a lists locales that are currently available. GREP_COLORS Controls how the --color option highlights output. Its value is a colon-separated list of capabilities that defaults to ms=01;31:mc=01;31:sl=:cx=:fn=35:ln=32:bn=32:se=36 with the rv and ne boolean capabilities omitted (i.e., false). Supported capabilities are as follows. sl= SGR substring for whole selected lines (i.e., matching lines when the -v command-line option is omitted, or non-matching lines when -v is specified). If however the boolean rv capability and the -v command-line option are both specified, it applies to context matching lines instead. The default is empty (i.e., the terminal's default color pair). cx= SGR substring for whole context lines (i.e., non- matching lines when the -v command-line option is omitted, or matching lines when -v is specified). If however the boolean rv capability and the -v command-line option are both specified, it applies to selected non-matching lines instead. The default is empty (i.e., the terminal's default color pair). rv Boolean value that reverses (swaps) the meanings of the sl= and cx= capabilities when the -v command- line option is specified. The default is false (i.e., the capability is omitted). mt=01;31 SGR substring for matching non-empty text in any matching line (i.e., a selected line when the -v command-line option is omitted, or a context line when -v is specified). Setting this is equivalent to setting both ms= and mc= at once to the same value. The default is a bold red text foreground over the current line background. ms=01;31 SGR substring for matching non-empty text in a selected line. (This is only used when the -v command-line option is omitted.) The effect of the sl= (or cx= if rv) capability remains active when this kicks in. The default is a bold red text foreground over the current line background. mc=01;31 SGR substring for matching non-empty text in a context line. (This is only used when the -v command-line option is specified.) The effect of the cx= (or sl= if rv) capability remains active when this kicks in. The default is a bold red text foreground over the current line background. fn=35 SGR substring for file names prefixing any content line. The default is a magenta text foreground over the terminal's default background. ln=32 SGR substring for line numbers prefixing any content line. The default is a green text foreground over the terminal's default background. bn=32 SGR substring for byte offsets prefixing any content line. The default is a green text foreground over the terminal's default background. se=36 SGR substring for separators that are inserted between selected line fields (:), between context line fields, (-), and between groups of adjacent lines when nonzero context is specified (--). The default is a cyan text foreground over the terminal's default background. ne Boolean value that prevents clearing to the end of line using Erase in Line (EL) to Right (\33[K) each time a colorized item ends. This is needed on terminals on which EL is not supported. It is otherwise useful on terminals for which the back_color_erase (bce) boolean terminfo capability does not apply, when the chosen highlight colors do not affect the background, or when EL is too slow or causes too much flicker. The default is false (i.e., the capability is omitted). Note that boolean capabilities have no =... part. They are omitted (i.e., false) by default and become true when specified. See the Select Graphic Rendition (SGR) section in the documentation of the text terminal that is used for permitted values and their meaning as character attributes. These substring values are integers in decimal representation and can be concatenated with semicolons. grep takes care of assembling the result into a complete SGR sequence (\33[...m). Common values to concatenate include 1 for bold, 4 for underline, 5 for blink, 7 for inverse, 39 for default foreground color, 30 to 37 for foreground colors, 90 to 97 for 16-color mode foreground colors, 38;5;0 to 38;5;255 for 88-color and 256-color modes foreground colors, 49 for default background color, 40 to 47 for background colors, 100 to 107 for 16-color mode background colors, and 48;5;0 to 48;5;255 for 88-color and 256-color modes background colors. LC_ALL, LC_COLLATE, LANG These variables specify the locale for the LC_COLLATE category, which determines the collating sequence used to interpret range expressions like [a-z]. LC_ALL, LC_CTYPE, LANG These variables specify the locale for the LC_CTYPE category, which determines the type of characters, e.g., which characters are whitespace. This category also determines the character encoding, that is, whether text is encoded in UTF-8, ASCII, or some other encoding. In the C or POSIX locale, all characters are encoded as a single byte and every byte is a valid character. LC_ALL, LC_MESSAGES, LANG These variables specify the locale for the LC_MESSAGES category, which determines the language that grep uses for messages. The default C locale uses American English messages. POSIXLY_CORRECT If set, grep behaves as POSIX requires; otherwise, grep behaves more like other GNU programs. POSIX requires that options that follow file names must be treated as file names; by default, such options are permuted to the front of the operand list and are treated as options. Also, POSIX requires that unrecognized options be diagnosed as illegal, but since they are not really against the law the default is to diagnose them as invalid. NOTES top This man page is maintained only fitfully; the full documentation is often more up-to-date. COPYRIGHT top Copyright 1998-2000, 2002, 2005-2023 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. BUGS top Reporting Bugs Email bug reports to the bug-reporting address bug- grep@gnu.org. An email archive https://lists.gnu.org/mailman/listinfo/bug-grep and a bug tracker https://debbugs.gnu.org/cgi/pkgreport.cgi?package=grep are available. Known Bugs Large repetition counts in the {n,m} construct may cause grep to use lots of memory. In addition, certain other obscure regular expressions require exponential time and space, and may cause grep to run out of memory. Back-references are very slow, and may require exponential time. EXAMPLE top The following example outputs the location and contents of any line containing f and ending in .c, within all files in the current directory whose names contain g and end in .h. The -n option outputs line numbers, the -- argument treats expansions of *g*.h starting with - as file names not options, and the empty file /dev/null causes file names to be output even if only one file name happens to be of the form *g*.h. $ grep -n -- 'f.*\.c$' *g*.h /dev/null argmatch.h:1:/* definitions and prototypes for argmatch.c The only line that matches is line 1 of argmatch.h. Note that the regular expression syntax used in the pattern differs from the globbing syntax that the shell uses to match file names. SEE ALSO top Regular Manual Pages awk(1), cmp(1), diff(1), find(1), perl(1), sed(1), sort(1), xargs(1), read(2), pcre2(3), pcre2syntax(3), pcre2pattern(3), terminfo(5), glob(7), regex(7) Full Documentation A complete manual https://www.gnu.org/software/grep/manual/ is available. If the info and grep programs are properly installed at your site, the command info grep should give you access to the complete manual. COLOPHON top This page is part of the GNU grep (regular expression file search tool) project. Information about the project can be found at https://www.gnu.org/software/grep/. If you have a bug report for this manual page, send it to bug-grep@gnu.org. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/grep.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-09-14.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU grep 3.11.21-102b-dirty 2019-12-29 GREP(1) Pages that refer to this page: look(1), pmrep(1), sed(1), regex(3), regex(7), bridge(8), ip(8), tc(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. sed(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training sed(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | COMMAND SYNOPSIS | REGULAR EXPRESSIONS | BUGS | AUTHOR | COPYRIGHT | SEE ALSO | COLOPHON SED(1) User Commands SED(1) NAME top sed - stream editor for filtering and transforming text SYNOPSIS top sed [-V] [--version] [--help] [-n] [--quiet] [--silent] [-l N] [--line-length=N] [-u] [--unbuffered] [-E] [-r] [--regexp-extended] [-e script] [--expression=script] [-f script-file] [--file=script-file] [script-if-no-other-script] [file...] DESCRIPTION top Sed is a stream editor. A stream editor is used to perform basic text transformations on an input stream (a file or input from a pipeline). While in some ways similar to an editor which permits scripted edits (such as ed), sed works by making only one pass over the input(s), and is consequently more efficient. But it is sed's ability to filter text in a pipeline which particularly distinguishes it from other types of editors. -n, --quiet, --silent suppress automatic printing of pattern space --debug annotate program execution -e script, --expression=script add the script to the commands to be executed -f script-file, --file=script-file add the contents of script-file to the commands to be executed --follow-symlinks follow symlinks when processing in place -i[SUFFIX], --in-place[=SUFFIX] edit files in place (makes backup if SUFFIX supplied) -l N, --line-length=N specify the desired line-wrap length for the `l' command --posix disable all GNU extensions. -E, -r, --regexp-extended use extended regular expressions in the script (for portability use POSIX -E). -s, --separate consider files as separate rather than as a single, continuous long stream. --sandbox operate in sandbox mode (disable e/r/w commands). -u, --unbuffered load minimal amounts of data from the input files and flush the output buffers more often -z, --null-data separate lines by NUL characters --help display this help and exit --version output version information and exit If no -e, --expression, -f, or --file option is given, then the first non-option argument is taken as the sed script to interpret. All remaining arguments are names of input files; if no input files are specified, then the standard input is read. GNU sed home page: <https://www.gnu.org/software/sed/>. General help using GNU software: <https://www.gnu.org/gethelp/>. E-mail bug reports to: <bug-sed@gnu.org>. COMMAND SYNOPSIS top This is just a brief synopsis of sed commands to serve as a reminder to those who already know sed; other documentation (such as the texinfo document) must be consulted for fuller descriptions. Zero-address ``commands'' : label Label for b and t commands. #comment The comment extends until the next newline (or the end of a -e script fragment). } The closing bracket of a { } block. Zero- or One- address commands = Print the current line number. a \ text Append text, which has each embedded newline preceded by a backslash. i \ text Insert text, which has each embedded newline preceded by a backslash. q [exit-code] Immediately quit the sed script without processing any more input, except that if auto-print is not disabled the current pattern space will be printed. The exit code argument is a GNU extension. Q [exit-code] Immediately quit the sed script without processing any more input. This is a GNU extension. r filename Append text read from filename. R filename Append a line read from filename. Each invocation of the command reads a line from the file. This is a GNU extension. Commands which accept address ranges { Begin a block of commands (end with a }). b label Branch to label; if label is omitted, branch to end of script. c \ text Replace the selected lines with text, which has each embedded newline preceded by a backslash. d Delete pattern space. Start next cycle. D If pattern space contains no newline, start a normal new cycle as if the d command was issued. Otherwise, delete text in the pattern space up to the first newline, and restart cycle with the resultant pattern space, without reading a new line of input. h H Copy/append pattern space to hold space. g G Copy/append hold space to pattern space. l List out the current line in a ``visually unambiguous'' form. l width List out the current line in a ``visually unambiguous'' form, breaking it at width characters. This is a GNU extension. n N Read/append the next line of input into the pattern space. p Print the current pattern space. P Print up to the first embedded newline of the current pattern space. s/regexp/replacement/ Attempt to match regexp against the pattern space. If successful, replace that portion matched with replacement. The replacement may contain the special character & to refer to that portion of the pattern space which matched, and the special escapes \1 through \9 to refer to the corresponding matching sub-expressions in the regexp. t label If a s/// has done a successful substitution since the last input line was read and since the last t or T command, then branch to label; if label is omitted, branch to end of script. T label If no s/// has done a successful substitution since the last input line was read and since the last t or T command, then branch to label; if label is omitted, branch to end of script. This is a GNU extension. w filename Write the current pattern space to filename. W filename Write the first line of the current pattern space to filename. This is a GNU extension. x Exchange the contents of the hold and pattern spaces. y/source/dest/ Transliterate the characters in the pattern space which appear in source to the corresponding character in dest. Addresses Sed commands can be given with no addresses, in which case the command will be executed for all input lines; with one address, in which case the command will only be executed for input lines which match that address; or with two addresses, in which case the command will be executed for all input lines which match the inclusive range of lines starting from the first address and continuing to the second address. Three things to note about address ranges: the syntax is addr1,addr2 (i.e., the addresses are separated by a comma); the line which addr1 matched will always be accepted, even if addr2 selects an earlier line; and if addr2 is a regexp, it will not be tested against the line that addr1 matched. After the address (or address-range), and before the command, a ! may be inserted, which specifies that the command shall only be executed if the address (or address-range) does not match. The following address types are supported: number Match only the specified line number (which increments cumulatively across files, unless the -s option is specified on the command line). first~step Match every step'th line starting with line first. For example, ``sed -n 1~2p'' will print all the odd-numbered lines in the input stream, and the address 2~5 will match every fifth line, starting with the second. first can be zero; in this case, sed operates as if it were equal to step. (This is an extension.) $ Match the last line. /regexp/ Match lines matching the regular expression regexp. Matching is performed on the current pattern space, which can be modified with commands such as ``s///''. \cregexpc Match lines matching the regular expression regexp. The c may be any character. GNU sed also supports some special 2-address forms: 0,addr2 Start out in "matched first address" state, until addr2 is found. This is similar to 1,addr2, except that if addr2 matches the very first line of input the 0,addr2 form will be at the end of its range, whereas the 1,addr2 form will still be at the beginning of its range. This works only when addr2 is a regular expression. addr1,+N Will match addr1 and the N lines following addr1. addr1,~N Will match addr1 and the lines following addr1 until the next line whose input line number is a multiple of N. REGULAR EXPRESSIONS top POSIX.2 BREs should be supported, but they aren't completely because of performance problems. The \n sequence in a regular expression matches the newline character, and similarly for \a, \t, and other sequences. The -E option switches to using extended regular expressions instead; it has been supported for years by GNU sed, and is now included in POSIX. BUGS top E-mail bug reports to bug-sed@gnu.org. Also, please include the output of ``sed --version'' in the body of your report if at all possible. AUTHOR top Written by Jay Fenlason, Tom Lord, Ken Pizzini, Paolo Bonzini, Jim Meyering, and Assaf Gordon. This sed program was built with SELinux support. SELinux is enabled on this system. GNU sed home page: <https://www.gnu.org/software/sed/>. General help using GNU software: <https://www.gnu.org/gethelp/>. E-mail bug reports to: <bug-sed@gnu.org>. COPYRIGHT top Copyright 2022 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top awk(1), ed(1), grep(1), tr(1), perlre(1), sed.info, any of various books on sed, the sed FAQ (http://sed.sf.net/grabbag/tutorials/sedfaq.txt), http://sed.sf.net/grabbag/. The full documentation for sed is maintained as a Texinfo manual. If the info and sed programs are properly installed at your site, the command info sed should give you access to the complete manual. COLOPHON top This page is part of the sed (stream-oriented editor) project. Information about the project can be found at http://www.gnu.org/software/sed/. If you have a bug report for this manual page, send it to bug-sed@gnu.org. This page was obtained from the tarball sed-4.9.tar.gz fetched from https://www.gnu.org/software/sed/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU sed 4.9 November 2022 SED(1) Pages that refer to this page: gawk(1), grep(1), iostat2pcp(1), pmdaopenmetrics(1), pmlogrewrite(1), sheet2pcp(1), cpuset(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all contents form the files that contain the case insensitive regex 'stringtofind' in maximum 1 level down the / directory excluding other partitions Bash Command:<START>find / -maxdepth 1 -xdev -type f -exec grep -i "stringtofind" -l {} \; -exec sed -i '/./d' {} \;<END>

Delete all contents form the files that contain the case insensitive regex 'stringtofind' in maximum 1 level down the / directory excluding other partitions

find / -maxdepth 1 -xdev -type f -exec grep -i "stringtofind" -q "{}" \; -print0 | xargs -0 sed '/./d'

['sed', 'xargs', 'grep', 'find']

Output a Bash command to accomplish the following task. Task: Delete all contents form the files that contain the case insensitive regex 'stringtofind' in maximum 1 level down the / directory excluding other partitions Bash Command:<START>find / -maxdepth 1 -xdev -type f -exec grep -i "stringtofind" -q "{}" \; -print0 | xargs -0 sed '/./d'<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # sed\n\n> Edit text in a scriptable manner.\n> See also: `awk`, `ed`.\n> More information: <https://www.gnu.org/software/sed/manual/sed.html>.\n\n- Replace all `apple` (basic regex) occurrences with `mango` (basic regex) in all input lines and print the result to `stdout`:\n\n`{{command}} | sed 's/apple/mango/g'`\n\n- Replace all `apple` (extended regex) occurrences with `APPLE` (extended regex) in all input lines and print the result to `stdout`:\n\n`{{command}} | sed -E 's/(apple)/\U\1/g'`\n\n- Replace all `apple` (basic regex) occurrences with `mango` (basic regex) in a specific file and overwrite the original file in place:\n\n`sed -i 's/apple/mango/g' {{path/to/file}}`\n\n- Execute a specific script [f]ile and print the result to `stdout`:\n\n`{{command}} | sed -f {{path/to/script.sed}}`\n\n- Print just the first line to `stdout`:\n\n`{{command}} | sed -n '1p'`\n\n- [d]elete the first line of a file:\n\n`sed -i 1d {{path/to/file}}`\n\n- [i]nsert a new line at the first line of a file:\n\n`sed -i '1i\your new line text\' {{path/to/file}}`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # grep\n\n> Find patterns in files using regular expressions.\n> More information: <https://www.gnu.org/software/grep/manual/grep.html>.\n\n- Search for a pattern within a file:\n\n`grep "{{search_pattern}}" {{path/to/file}}`\n\n- Search for an exact string (disables regular expressions):\n\n`grep --fixed-strings "{{exact_string}}" {{path/to/file}}`\n\n- Search for a pattern in all files recursively in a directory, showing line numbers of matches, ignoring binary files:\n\n`grep --recursive --line-number --binary-files={{without-match}} "{{search_pattern}}" {{path/to/directory}}`\n\n- Use extended regular expressions (supports `?`, `+`, `{}`, `()` and `|`), in case-insensitive mode:\n\n`grep --extended-regexp --ignore-case "{{search_pattern}}" {{path/to/file}}`\n\n- Print 3 lines of context around, before, or after each match:\n\n`grep --{{context|before-context|after-context}}={{3}} "{{search_pattern}}" {{path/to/file}}`\n\n- Print file name and line number for each match with color output:\n\n`grep --with-filename --line-number --color=always "{{search_pattern}}" {{path/to/file}}`\n\n- Search for lines matching a pattern, printing only the matched text:\n\n`grep --only-matching "{{search_pattern}}" {{path/to/file}}`\n\n- Search `stdin` for lines that do not match a pattern:\n\n`cat {{path/to/file}} | grep --invert-match "{{search_pattern}}"`\n # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n Task: Delete all contents form the files that contain the case insensitive regex 'stringtofind' in maximum 1 level down the / directory excluding other partitions Bash Command:<START>find / -maxdepth 1 -xdev -type f -exec grep -i "stringtofind" -q "{}" \; -print0 | xargs -0 sed '/./d'<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: sed(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training sed(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | COMMAND SYNOPSIS | REGULAR EXPRESSIONS | BUGS | AUTHOR | COPYRIGHT | SEE ALSO | COLOPHON SED(1) User Commands SED(1) NAME top sed - stream editor for filtering and transforming text SYNOPSIS top sed [-V] [--version] [--help] [-n] [--quiet] [--silent] [-l N] [--line-length=N] [-u] [--unbuffered] [-E] [-r] [--regexp-extended] [-e script] [--expression=script] [-f script-file] [--file=script-file] [script-if-no-other-script] [file...] DESCRIPTION top Sed is a stream editor. A stream editor is used to perform basic text transformations on an input stream (a file or input from a pipeline). While in some ways similar to an editor which permits scripted edits (such as ed), sed works by making only one pass over the input(s), and is consequently more efficient. But it is sed's ability to filter text in a pipeline which particularly distinguishes it from other types of editors. -n, --quiet, --silent suppress automatic printing of pattern space --debug annotate program execution -e script, --expression=script add the script to the commands to be executed -f script-file, --file=script-file add the contents of script-file to the commands to be executed --follow-symlinks follow symlinks when processing in place -i[SUFFIX], --in-place[=SUFFIX] edit files in place (makes backup if SUFFIX supplied) -l N, --line-length=N specify the desired line-wrap length for the `l' command --posix disable all GNU extensions. -E, -r, --regexp-extended use extended regular expressions in the script (for portability use POSIX -E). -s, --separate consider files as separate rather than as a single, continuous long stream. --sandbox operate in sandbox mode (disable e/r/w commands). -u, --unbuffered load minimal amounts of data from the input files and flush the output buffers more often -z, --null-data separate lines by NUL characters --help display this help and exit --version output version information and exit If no -e, --expression, -f, or --file option is given, then the first non-option argument is taken as the sed script to interpret. All remaining arguments are names of input files; if no input files are specified, then the standard input is read. GNU sed home page: <https://www.gnu.org/software/sed/>. General help using GNU software: <https://www.gnu.org/gethelp/>. E-mail bug reports to: <bug-sed@gnu.org>. COMMAND SYNOPSIS top This is just a brief synopsis of sed commands to serve as a reminder to those who already know sed; other documentation (such as the texinfo document) must be consulted for fuller descriptions. Zero-address ``commands'' : label Label for b and t commands. #comment The comment extends until the next newline (or the end of a -e script fragment). } The closing bracket of a { } block. Zero- or One- address commands = Print the current line number. a \ text Append text, which has each embedded newline preceded by a backslash. i \ text Insert text, which has each embedded newline preceded by a backslash. q [exit-code] Immediately quit the sed script without processing any more input, except that if auto-print is not disabled the current pattern space will be printed. The exit code argument is a GNU extension. Q [exit-code] Immediately quit the sed script without processing any more input. This is a GNU extension. r filename Append text read from filename. R filename Append a line read from filename. Each invocation of the command reads a line from the file. This is a GNU extension. Commands which accept address ranges { Begin a block of commands (end with a }). b label Branch to label; if label is omitted, branch to end of script. c \ text Replace the selected lines with text, which has each embedded newline preceded by a backslash. d Delete pattern space. Start next cycle. D If pattern space contains no newline, start a normal new cycle as if the d command was issued. Otherwise, delete text in the pattern space up to the first newline, and restart cycle with the resultant pattern space, without reading a new line of input. h H Copy/append pattern space to hold space. g G Copy/append hold space to pattern space. l List out the current line in a ``visually unambiguous'' form. l width List out the current line in a ``visually unambiguous'' form, breaking it at width characters. This is a GNU extension. n N Read/append the next line of input into the pattern space. p Print the current pattern space. P Print up to the first embedded newline of the current pattern space. s/regexp/replacement/ Attempt to match regexp against the pattern space. If successful, replace that portion matched with replacement. The replacement may contain the special character & to refer to that portion of the pattern space which matched, and the special escapes \1 through \9 to refer to the corresponding matching sub-expressions in the regexp. t label If a s/// has done a successful substitution since the last input line was read and since the last t or T command, then branch to label; if label is omitted, branch to end of script. T label If no s/// has done a successful substitution since the last input line was read and since the last t or T command, then branch to label; if label is omitted, branch to end of script. This is a GNU extension. w filename Write the current pattern space to filename. W filename Write the first line of the current pattern space to filename. This is a GNU extension. x Exchange the contents of the hold and pattern spaces. y/source/dest/ Transliterate the characters in the pattern space which appear in source to the corresponding character in dest. Addresses Sed commands can be given with no addresses, in which case the command will be executed for all input lines; with one address, in which case the command will only be executed for input lines which match that address; or with two addresses, in which case the command will be executed for all input lines which match the inclusive range of lines starting from the first address and continuing to the second address. Three things to note about address ranges: the syntax is addr1,addr2 (i.e., the addresses are separated by a comma); the line which addr1 matched will always be accepted, even if addr2 selects an earlier line; and if addr2 is a regexp, it will not be tested against the line that addr1 matched. After the address (or address-range), and before the command, a ! may be inserted, which specifies that the command shall only be executed if the address (or address-range) does not match. The following address types are supported: number Match only the specified line number (which increments cumulatively across files, unless the -s option is specified on the command line). first~step Match every step'th line starting with line first. For example, ``sed -n 1~2p'' will print all the odd-numbered lines in the input stream, and the address 2~5 will match every fifth line, starting with the second. first can be zero; in this case, sed operates as if it were equal to step. (This is an extension.) $ Match the last line. /regexp/ Match lines matching the regular expression regexp. Matching is performed on the current pattern space, which can be modified with commands such as ``s///''. \cregexpc Match lines matching the regular expression regexp. The c may be any character. GNU sed also supports some special 2-address forms: 0,addr2 Start out in "matched first address" state, until addr2 is found. This is similar to 1,addr2, except that if addr2 matches the very first line of input the 0,addr2 form will be at the end of its range, whereas the 1,addr2 form will still be at the beginning of its range. This works only when addr2 is a regular expression. addr1,+N Will match addr1 and the N lines following addr1. addr1,~N Will match addr1 and the lines following addr1 until the next line whose input line number is a multiple of N. REGULAR EXPRESSIONS top POSIX.2 BREs should be supported, but they aren't completely because of performance problems. The \n sequence in a regular expression matches the newline character, and similarly for \a, \t, and other sequences. The -E option switches to using extended regular expressions instead; it has been supported for years by GNU sed, and is now included in POSIX. BUGS top E-mail bug reports to bug-sed@gnu.org. Also, please include the output of ``sed --version'' in the body of your report if at all possible. AUTHOR top Written by Jay Fenlason, Tom Lord, Ken Pizzini, Paolo Bonzini, Jim Meyering, and Assaf Gordon. This sed program was built with SELinux support. SELinux is enabled on this system. GNU sed home page: <https://www.gnu.org/software/sed/>. General help using GNU software: <https://www.gnu.org/gethelp/>. E-mail bug reports to: <bug-sed@gnu.org>. COPYRIGHT top Copyright 2022 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top awk(1), ed(1), grep(1), tr(1), perlre(1), sed.info, any of various books on sed, the sed FAQ (http://sed.sf.net/grabbag/tutorials/sedfaq.txt), http://sed.sf.net/grabbag/. The full documentation for sed is maintained as a Texinfo manual. If the info and sed programs are properly installed at your site, the command info sed should give you access to the complete manual. COLOPHON top This page is part of the sed (stream-oriented editor) project. Information about the project can be found at http://www.gnu.org/software/sed/. If you have a bug report for this manual page, send it to bug-sed@gnu.org. This page was obtained from the tarball sed-4.9.tar.gz fetched from https://www.gnu.org/software/sed/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU sed 4.9 November 2022 SED(1) Pages that refer to this page: gawk(1), grep(1), iostat2pcp(1), pmdaopenmetrics(1), pmlogrewrite(1), sheet2pcp(1), cpuset(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. grep(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training grep(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | REGULAR EXPRESSIONS | EXIT STATUS | ENVIRONMENT | NOTES | COPYRIGHT | BUGS | EXAMPLE | SEE ALSO | COLOPHON GREP(1) User Commands GREP(1) NAME top grep - print lines that match patterns SYNOPSIS top grep [OPTION...] PATTERNS [FILE...] grep [OPTION...] -e PATTERNS ... [FILE...] grep [OPTION...] -f PATTERN_FILE ... [FILE...] DESCRIPTION top grep searches for PATTERNS in each FILE. PATTERNS is one or more patterns separated by newline characters, and grep prints each line that matches a pattern. Typically PATTERNS should be quoted when grep is used in a shell command. A FILE of - stands for standard input. If no FILE is given, recursive searches examine the working directory, and nonrecursive searches read standard input. OPTIONS top Generic Program Information --help Output a usage message and exit. -V, --version Output the version number of grep and exit. Pattern Syntax -E, --extended-regexp Interpret PATTERNS as extended regular expressions (EREs, see below). -F, --fixed-strings Interpret PATTERNS as fixed strings, not regular expressions. -G, --basic-regexp Interpret PATTERNS as basic regular expressions (BREs, see below). This is the default. -P, --perl-regexp Interpret PATTERNS as Perl-compatible regular expressions (PCREs). This option is experimental when combined with the -z (--null-data) option, and grep -P may warn of unimplemented features. Matching Control -e PATTERNS, --regexp=PATTERNS Use PATTERNS as the patterns. If this option is used multiple times or is combined with the -f (--file) option, search for all patterns given. This option can be used to protect a pattern beginning with -. -f FILE, --file=FILE Obtain patterns from FILE, one per line. If this option is used multiple times or is combined with the -e (--regexp) option, search for all patterns given. The empty file contains zero patterns, and therefore matches nothing. If FILE is - , read patterns from standard input. -i, --ignore-case Ignore case distinctions in patterns and input data, so that characters that differ only in case match each other. --no-ignore-case Do not ignore case distinctions in patterns and input data. This is the default. This option is useful for passing to shell scripts that already use -i, to cancel its effects because the two options override each other. -v, --invert-match Invert the sense of matching, to select non-matching lines. -w, --word-regexp Select only those lines containing matches that form whole words. The test is that the matching substring must either be at the beginning of the line, or preceded by a non-word constituent character. Similarly, it must be either at the end of the line or followed by a non-word constituent character. Word-constituent characters are letters, digits, and the underscore. This option has no effect if -x is also specified. -x, --line-regexp Select only those matches that exactly match the whole line. For a regular expression pattern, this is like parenthesizing the pattern and then surrounding it with ^ and $. General Output Control -c, --count Suppress normal output; instead print a count of matching lines for each input file. With the -v, --invert-match option (see above), count non-matching lines. --color[=WHEN], --colour[=WHEN] Surround the matched (non-empty) strings, matching lines, context lines, file names, line numbers, byte offsets, and separators (for fields and groups of context lines) with escape sequences to display them in color on the terminal. The colors are defined by the environment variable GREP_COLORS. WHEN is never, always, or auto. -L, --files-without-match Suppress normal output; instead print the name of each input file from which no output would normally have been printed. -l, --files-with-matches Suppress normal output; instead print the name of each input file from which output would normally have been printed. Scanning each input file stops upon first match. -m NUM, --max-count=NUM Stop reading a file after NUM matching lines. If NUM is zero, grep stops right away without reading input. A NUM of -1 is treated as infinity and grep does not stop; this is the default. If the input is standard input from a regular file, and NUM matching lines are output, grep ensures that the standard input is positioned to just after the last matching line before exiting, regardless of the presence of trailing context lines. This enables a calling process to resume a search. When grep stops after NUM matching lines, it outputs any trailing context lines. When the -c or --count option is also used, grep does not output a count greater than NUM. When the -v or --invert-match option is also used, grep stops after outputting NUM non-matching lines. -o, --only-matching Print only the matched (non-empty) parts of a matching line, with each such part on a separate output line. -q, --quiet, --silent Quiet; do not write anything to standard output. Exit immediately with zero status if any match is found, even if an error was detected. Also see the -s or --no-messages option. -s, --no-messages Suppress error messages about nonexistent or unreadable files. Output Line Prefix Control -b, --byte-offset Print the 0-based byte offset within the input file before each line of output. If -o (--only-matching) is specified, print the offset of the matching part itself. -H, --with-filename Print the file name for each match. This is the default when there is more than one file to search. This is a GNU extension. -h, --no-filename Suppress the prefixing of file names on output. This is the default when there is only one file (or only standard input) to search. --label=LABEL Display input actually coming from standard input as input coming from file LABEL. This can be useful for commands that transform a file's contents before searching, e.g., gzip -cd foo.gz | grep --label=foo -H 'some pattern'. See also the -H option. -n, --line-number Prefix each line of output with the 1-based line number within its input file. -T, --initial-tab Make sure that the first character of actual line content lies on a tab stop, so that the alignment of tabs looks normal. This is useful with options that prefix their output to the actual content: -H,-n, and -b. In order to improve the probability that lines from a single file will all start at the same column, this also causes the line number and byte offset (if present) to be printed in a minimum size field width. -Z, --null Output a zero byte (the ASCII NUL character) instead of the character that normally follows a file name. For example, grep -lZ outputs a zero byte after each file name instead of the usual newline. This option makes the output unambiguous, even in the presence of file names containing unusual characters like newlines. This option can be used with commands like find -print0, perl -0, sort -z, and xargs -0 to process arbitrary file names, even those that contain newline characters. Context Line Control -A NUM, --after-context=NUM Print NUM lines of trailing context after matching lines. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. -B NUM, --before-context=NUM Print NUM lines of leading context before matching lines. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. -C NUM, -NUM, --context=NUM Print NUM lines of output context. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given. --group-separator=SEP When -A, -B, or -C are in use, print SEP instead of -- between groups of lines. --no-group-separator When -A, -B, or -C are in use, do not print a separator between groups of lines. File and Directory Selection -a, --text Process a binary file as if it were text; this is equivalent to the --binary-files=text option. --binary-files=TYPE If a file's data or metadata indicate that the file contains binary data, assume that the file is of type TYPE. Non-text bytes indicate binary data; these are either output bytes that are improperly encoded for the current locale, or null input bytes when the -z option is not given. By default, TYPE is binary, and grep suppresses output after null input binary data is discovered, and suppresses output lines that contain improperly encoded data. When some output is suppressed, grep follows any output with a message to standard error saying that a binary file matches. If TYPE is without-match, when grep discovers null input binary data it assumes that the rest of the file does not match; this is equivalent to the -I option. If TYPE is text, grep processes a binary file as if it were text; this is equivalent to the -a option. When type is binary, grep may treat non-text bytes as line terminators even without the -z option. This means choosing binary versus text can affect whether a pattern matches a file. For example, when type is binary the pattern q$ might match q immediately followed by a null byte, even though this is not matched when type is text. Conversely, when type is binary the pattern . (period) might not match a null byte. Warning: The -a option might output binary garbage, which can have nasty side effects if the output is a terminal and if the terminal driver interprets some of it as commands. On the other hand, when reading files whose text encodings are unknown, it can be helpful to use -a or to set LC_ALL='C' in the environment, in order to find more matches even if the matches are unsafe for direct display. -D ACTION, --devices=ACTION If an input file is a device, FIFO or socket, use ACTION to process it. By default, ACTION is read, which means that devices are read just as if they were ordinary files. If ACTION is skip, devices are silently skipped. -d ACTION, --directories=ACTION If an input file is a directory, use ACTION to process it. By default, ACTION is read, i.e., read directories just as if they were ordinary files. If ACTION is skip, silently skip directories. If ACTION is recurse, read all files under each directory, recursively, following symbolic links only if they are on the command line. This is equivalent to the -r option. --exclude=GLOB Skip any command-line file with a name suffix that matches the pattern GLOB, using wildcard matching; a name suffix is either the whole name, or a trailing part that starts with a non-slash character immediately after a slash (/) in the name. When searching recursively, skip any subfile whose base name matches GLOB; the base name is the part after the last slash. A pattern can use *, ?, and [...] as wildcards, and \ to quote a wildcard or backslash character literally. --exclude-from=FILE Skip files whose base name matches any of the file-name globs read from FILE (using wildcard matching as described under --exclude). --exclude-dir=GLOB Skip any command-line directory with a name suffix that matches the pattern GLOB. When searching recursively, skip any subdirectory whose base name matches GLOB. Ignore any redundant trailing slashes in GLOB. -I Process a binary file as if it did not contain matching data; this is equivalent to the --binary-files=without-match option. --include=GLOB Search only files whose base name matches GLOB (using wildcard matching as described under --exclude). If contradictory --include and --exclude options are given, the last matching one wins. If no --include or --exclude options match, a file is included unless the first such option is --include. -r, --recursive Read all files under each directory, recursively, following symbolic links only if they are on the command line. Note that if no file operand is given, grep searches the working directory. This is equivalent to the -d recurse option. -R, --dereference-recursive Read all files under each directory, recursively. Follow all symbolic links, unlike -r. Other Options --line-buffered Use line buffering on output. This can cause a performance penalty. -U, --binary Treat the file(s) as binary. By default, under MS-DOS and MS-Windows, grep guesses whether a file is text or binary as described for the --binary-files option. If grep decides the file is a text file, it strips the CR characters from the original file contents (to make regular expressions with ^ and $ work correctly). Specifying -U overrules this guesswork, causing all files to be read and passed to the matching mechanism verbatim; if the file is a text file with CR/LF pairs at the end of each line, this will cause some regular expressions to fail. This option has no effect on platforms other than MS-DOS and MS-Windows. -z, --null-data Treat input and output data as sequences of lines, each terminated by a zero byte (the ASCII NUL character) instead of a newline. Like the -Z or --null option, this option can be used with commands like sort -z to process arbitrary file names. REGULAR EXPRESSIONS top A regular expression is a pattern that describes a set of strings. Regular expressions are constructed analogously to arithmetic expressions, by using various operators to combine smaller expressions. grep understands three different versions of regular expression syntax: basic (BRE), extended (ERE) and perl (PCRE). In GNU grep, basic and extended regular expressions are merely different notations for the same pattern-matching functionality. In other implementations, basic regular expressions are ordinarily less powerful than extended, though occasionally it is the other way around. The following description applies to extended regular expressions; differences for basic regular expressions are summarized afterwards. Perl-compatible regular expressions have different functionality, and are documented in pcre2syntax(3) and pcre2pattern(3), but work only if PCRE support is enabled. The fundamental building blocks are the regular expressions that match a single character. Most characters, including all letters and digits, are regular expressions that match themselves. Any meta-character with special meaning may be quoted by preceding it with a backslash. The period . matches any single character. It is unspecified whether it matches an encoding error. Character Classes and Bracket Expressions A bracket expression is a list of characters enclosed by [ and ]. It matches any single character in that list. If the first character of the list is the caret ^ then it matches any character not in the list; it is unspecified whether it matches an encoding error. For example, the regular expression [0123456789] matches any single digit. Within a bracket expression, a range expression consists of two characters separated by a hyphen. It matches any single character that sorts between the two characters, inclusive, using the locale's collating sequence and character set. For example, in the default C locale, [a-d] is equivalent to [abcd]. Many locales sort characters in dictionary order, and in these locales [a-d] is typically not equivalent to [abcd]; it might be equivalent to [aBbCcDd], for example. To obtain the traditional interpretation of bracket expressions, you can use the C locale by setting the LC_ALL environment variable to the value C. Finally, certain named classes of characters are predefined within bracket expressions, as follows. Their names are self explanatory, and they are [:alnum:], [:alpha:], [:blank:], [:cntrl:], [:digit:], [:graph:], [:lower:], [:print:], [:punct:], [:space:], [:upper:], and [:xdigit:]. For example, [[:alnum:]] means the character class of numbers and letters in the current locale. In the C locale and ASCII character set encoding, this is the same as [0-9A-Za-z]. (Note that the brackets in these class names are part of the symbolic names, and must be included in addition to the brackets delimiting the bracket expression.) Most meta-characters lose their special meaning inside bracket expressions. To include a literal ] place it first in the list. Similarly, to include a literal ^ place it anywhere but first. Finally, to include a literal - place it last. Anchoring The caret ^ and the dollar sign $ are meta-characters that respectively match the empty string at the beginning and end of a line. The Backslash Character and Special Expressions The symbols \< and \> respectively match the empty string at the beginning and end of a word. The symbol \b matches the empty string at the edge of a word, and \B matches the empty string provided it's not at the edge of a word. The symbol \w is a synonym for [_[:alnum:]] and \W is a synonym for [^_[:alnum:]]. Repetition A regular expression may be followed by one of several repetition operators: ? The preceding item is optional and matched at most once. * The preceding item will be matched zero or more times. + The preceding item will be matched one or more times. {n} The preceding item is matched exactly n times. {n,} The preceding item is matched n or more times. {,m} The preceding item is matched at most m times. This is a GNU extension. {n,m} The preceding item is matched at least n times, but not more than m times. Concatenation Two regular expressions may be concatenated; the resulting regular expression matches any string formed by concatenating two substrings that respectively match the concatenated expressions. Alternation Two regular expressions may be joined by the infix operator |; the resulting regular expression matches any string matching either alternate expression. Precedence Repetition takes precedence over concatenation, which in turn takes precedence over alternation. A whole expression may be enclosed in parentheses to override these precedence rules and form a subexpression. Back-references and Subexpressions The back-reference \n, where n is a single digit, matches the substring previously matched by the nth parenthesized subexpression of the regular expression. Basic vs Extended Regular Expressions In basic regular expressions the meta-characters ?, +, {, |, (, and ) lose their special meaning; instead use the backslashed versions \?, \+, \{, \|, \(, and \). EXIT STATUS top Normally the exit status is 0 if a line is selected, 1 if no lines were selected, and 2 if an error occurred. However, if the -q or --quiet or --silent is used and a line is selected, the exit status is 0 even if an error occurred. ENVIRONMENT top The behavior of grep is affected by the following environment variables. The locale for category LC_foo is specified by examining the three environment variables LC_ALL, LC_foo, LANG, in that order. The first of these variables that is set specifies the locale. For example, if LC_ALL is not set, but LC_MESSAGES is set to pt_BR, then the Brazilian Portuguese locale is used for the LC_MESSAGES category. The C locale is used if none of these environment variables are set, if the locale catalog is not installed, or if grep was not compiled with national language support (NLS). The shell command locale -a lists locales that are currently available. GREP_COLORS Controls how the --color option highlights output. Its value is a colon-separated list of capabilities that defaults to ms=01;31:mc=01;31:sl=:cx=:fn=35:ln=32:bn=32:se=36 with the rv and ne boolean capabilities omitted (i.e., false). Supported capabilities are as follows. sl= SGR substring for whole selected lines (i.e., matching lines when the -v command-line option is omitted, or non-matching lines when -v is specified). If however the boolean rv capability and the -v command-line option are both specified, it applies to context matching lines instead. The default is empty (i.e., the terminal's default color pair). cx= SGR substring for whole context lines (i.e., non- matching lines when the -v command-line option is omitted, or matching lines when -v is specified). If however the boolean rv capability and the -v command-line option are both specified, it applies to selected non-matching lines instead. The default is empty (i.e., the terminal's default color pair). rv Boolean value that reverses (swaps) the meanings of the sl= and cx= capabilities when the -v command- line option is specified. The default is false (i.e., the capability is omitted). mt=01;31 SGR substring for matching non-empty text in any matching line (i.e., a selected line when the -v command-line option is omitted, or a context line when -v is specified). Setting this is equivalent to setting both ms= and mc= at once to the same value. The default is a bold red text foreground over the current line background. ms=01;31 SGR substring for matching non-empty text in a selected line. (This is only used when the -v command-line option is omitted.) The effect of the sl= (or cx= if rv) capability remains active when this kicks in. The default is a bold red text foreground over the current line background. mc=01;31 SGR substring for matching non-empty text in a context line. (This is only used when the -v command-line option is specified.) The effect of the cx= (or sl= if rv) capability remains active when this kicks in. The default is a bold red text foreground over the current line background. fn=35 SGR substring for file names prefixing any content line. The default is a magenta text foreground over the terminal's default background. ln=32 SGR substring for line numbers prefixing any content line. The default is a green text foreground over the terminal's default background. bn=32 SGR substring for byte offsets prefixing any content line. The default is a green text foreground over the terminal's default background. se=36 SGR substring for separators that are inserted between selected line fields (:), between context line fields, (-), and between groups of adjacent lines when nonzero context is specified (--). The default is a cyan text foreground over the terminal's default background. ne Boolean value that prevents clearing to the end of line using Erase in Line (EL) to Right (\33[K) each time a colorized item ends. This is needed on terminals on which EL is not supported. It is otherwise useful on terminals for which the back_color_erase (bce) boolean terminfo capability does not apply, when the chosen highlight colors do not affect the background, or when EL is too slow or causes too much flicker. The default is false (i.e., the capability is omitted). Note that boolean capabilities have no =... part. They are omitted (i.e., false) by default and become true when specified. See the Select Graphic Rendition (SGR) section in the documentation of the text terminal that is used for permitted values and their meaning as character attributes. These substring values are integers in decimal representation and can be concatenated with semicolons. grep takes care of assembling the result into a complete SGR sequence (\33[...m). Common values to concatenate include 1 for bold, 4 for underline, 5 for blink, 7 for inverse, 39 for default foreground color, 30 to 37 for foreground colors, 90 to 97 for 16-color mode foreground colors, 38;5;0 to 38;5;255 for 88-color and 256-color modes foreground colors, 49 for default background color, 40 to 47 for background colors, 100 to 107 for 16-color mode background colors, and 48;5;0 to 48;5;255 for 88-color and 256-color modes background colors. LC_ALL, LC_COLLATE, LANG These variables specify the locale for the LC_COLLATE category, which determines the collating sequence used to interpret range expressions like [a-z]. LC_ALL, LC_CTYPE, LANG These variables specify the locale for the LC_CTYPE category, which determines the type of characters, e.g., which characters are whitespace. This category also determines the character encoding, that is, whether text is encoded in UTF-8, ASCII, or some other encoding. In the C or POSIX locale, all characters are encoded as a single byte and every byte is a valid character. LC_ALL, LC_MESSAGES, LANG These variables specify the locale for the LC_MESSAGES category, which determines the language that grep uses for messages. The default C locale uses American English messages. POSIXLY_CORRECT If set, grep behaves as POSIX requires; otherwise, grep behaves more like other GNU programs. POSIX requires that options that follow file names must be treated as file names; by default, such options are permuted to the front of the operand list and are treated as options. Also, POSIX requires that unrecognized options be diagnosed as illegal, but since they are not really against the law the default is to diagnose them as invalid. NOTES top This man page is maintained only fitfully; the full documentation is often more up-to-date. COPYRIGHT top Copyright 1998-2000, 2002, 2005-2023 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. BUGS top Reporting Bugs Email bug reports to the bug-reporting address bug- grep@gnu.org. An email archive https://lists.gnu.org/mailman/listinfo/bug-grep and a bug tracker https://debbugs.gnu.org/cgi/pkgreport.cgi?package=grep are available. Known Bugs Large repetition counts in the {n,m} construct may cause grep to use lots of memory. In addition, certain other obscure regular expressions require exponential time and space, and may cause grep to run out of memory. Back-references are very slow, and may require exponential time. EXAMPLE top The following example outputs the location and contents of any line containing f and ending in .c, within all files in the current directory whose names contain g and end in .h. The -n option outputs line numbers, the -- argument treats expansions of *g*.h starting with - as file names not options, and the empty file /dev/null causes file names to be output even if only one file name happens to be of the form *g*.h. $ grep -n -- 'f.*\.c$' *g*.h /dev/null argmatch.h:1:/* definitions and prototypes for argmatch.c The only line that matches is line 1 of argmatch.h. Note that the regular expression syntax used in the pattern differs from the globbing syntax that the shell uses to match file names. SEE ALSO top Regular Manual Pages awk(1), cmp(1), diff(1), find(1), perl(1), sed(1), sort(1), xargs(1), read(2), pcre2(3), pcre2syntax(3), pcre2pattern(3), terminfo(5), glob(7), regex(7) Full Documentation A complete manual https://www.gnu.org/software/grep/manual/ is available. If the info and grep programs are properly installed at your site, the command info grep should give you access to the complete manual. COLOPHON top This page is part of the GNU grep (regular expression file search tool) project. Information about the project can be found at https://www.gnu.org/software/grep/. If you have a bug report for this manual page, send it to bug-grep@gnu.org. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/grep.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-09-14.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU grep 3.11.21-102b-dirty 2019-12-29 GREP(1) Pages that refer to this page: look(1), pmrep(1), sed(1), regex(3), regex(7), bridge(8), ip(8), tc(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all contents form the files that contain the case insensitive regex 'stringtofind' in maximum 1 level down the / directory excluding other partitions Bash Command:<START>find / -maxdepth 1 -xdev -type f -exec grep -i "stringtofind" -q "{}" \; -print0 | xargs -0 sed '/./d'<END>

Delete all directories found in $LOGDIR that are more than a work-week old

find $LOGDIR -type d -mtime +5 -exec rm -rf {} \;

['find', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all directories found in $LOGDIR that are more than a work-week old Bash Command:<START>find $LOGDIR -type d -mtime +5 -exec rm -rf {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all directories found in $LOGDIR that are more than a work-week old Bash Command:<START>find $LOGDIR -type d -mtime +5 -exec rm -rf {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all directories found in $LOGDIR that are more than a work-week old Bash Command:<START>find $LOGDIR -type d -mtime +5 -exec rm -rf {} \;<END>

Delete all directories in the /myDir directory tree

find /myDir -type d -delete

['find']

Output a Bash command to accomplish the following task. Task: Delete all directories in the /myDir directory tree Bash Command:<START>find /myDir -type d -delete<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n Task: Delete all directories in the /myDir directory tree Bash Command:<START>find /myDir -type d -delete<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all directories in the /myDir directory tree Bash Command:<START>find /myDir -type d -delete<END>

Delete all directories in the TBD directory that were modified more than 1 day ago

find /TBD -mtime +1 -type d | xargs rm -f -r

['find', 'xargs', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all directories in the TBD directory that were modified more than 1 day ago Bash Command:<START>find /TBD -mtime +1 -type d | xargs rm -f -r<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # xargs\n\n> Execute a command with piped arguments coming from another command, a file, etc.\n> The input is treated as a single block of text and split into separate pieces on spaces, tabs, newlines and end-of-file.\n> More information: <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/xargs.html>.\n\n- Run a command using the input data as arguments:\n\n`{{arguments_source}} | xargs {{command}}`\n\n- Run multiple chained commands on the input data:\n\n`{{arguments_source}} | xargs sh -c "{{command1}} && {{command2}} | {{command3}}"`\n\n- Delete all files with a `.backup` extension (`-print0` uses a null character to split file names, and `-0` uses it as delimiter):\n\n`find . -name {{'*.backup'}} -print0 | xargs -0 rm -v`\n\n- Execute the command once for each input line, replacing any occurrences of the placeholder (here marked as `_`) with the input line:\n\n`{{arguments_source}} | xargs -I _ {{command}} _ {{optional_extra_arguments}}`\n\n- Parallel runs of up to `max-procs` processes at a time; the default is 1. If `max-procs` is 0, xargs will run as many processes as possible at a time:\n\n`{{arguments_source}} | xargs -P {{max-procs}} {{command}}`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all directories in the TBD directory that were modified more than 1 day ago Bash Command:<START>find /TBD -mtime +1 -type d | xargs rm -f -r<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. xargs(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training xargs(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | STANDARDS CONFORMANCE | HISTORY | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON XARGS(1) General Commands Manual XARGS(1) NAME top xargs - build and execute command lines from standard input SYNOPSIS top xargs [options] [command [initial-arguments]] DESCRIPTION top This manual page documents the GNU version of xargs. xargs reads items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list of input items. In general, there will be many fewer invocations of command than there were items in the input. This will normally have significant performance benefits. Some commands can usefully be executed in parallel too; see the -P option. Because Unix filenames can contain blanks and newlines, this default behaviour is often problematic; filenames containing blanks and/or newlines are incorrectly processed by xargs. In these situations it is better to use the -0 option, which prevents such problems. When using this option you will need to ensure that the program which produces the input for xargs also uses a null character as a separator. If that program is GNU find for example, the -print0 option does this for you. If any invocation of the command exits with a status of 255, xargs will stop immediately without reading any further input. An error message is issued on stderr when this happens. OPTIONS top -0, --null Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally). Disables the end-of-file string, which is treated like any other argument. Useful when input items might contain white space, quote marks, or backslashes. The GNU find -print0 option produces input suitable for this mode. -a file, --arg-file=file Read items from file instead of standard input. If you use this option, stdin remains unchanged when commands are run. Otherwise, stdin is redirected from /dev/null. --delimiter=delim, -d delim Input items are terminated by the specified character. The specified delimiter may be a single character, a C- style character escape such as \n, or an octal or hexadecimal escape code. Octal and hexadecimal escape codes are understood as for the printf command. Multibyte characters are not supported. When processing the input, quotes and backslash are not special; every character in the input is taken literally. The -d option disables any end-of-file string, which is treated like any other argument. You can use this option when the input consists of simply newline-separated items, although it is almost always better to design your program to use --null where this is possible. -E eof-str Set the end-of-file string to eof-str. If the end-of-file string occurs as a line of input, the rest of the input is ignored. If neither -E nor -e is used, no end-of-file string is used. -e[eof-str], --eof[=eof-str] This option is a synonym for the -E option. Use -E instead, because it is POSIX compliant while this option is not. If eof-str is omitted, there is no end-of-file string. If neither -E nor -e is used, no end-of-file string is used. -I replace-str Replace occurrences of replace-str in the initial- arguments with names read from standard input. Also, unquoted blanks do not terminate input items; instead the separator is the newline character. Implies -x and -L 1. -i[replace-str], --replace[=replace-str] This option is a synonym for -Ireplace-str if replace-str is specified. If the replace-str argument is missing, the effect is the same as -I{}. The -i option is deprecated; use -I instead. -L max-lines Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x. -l[max-lines], --max-lines[=max-lines] Synonym for the -L option. Unlike -L, the max-lines argument is optional. If max-lines is not specified, it defaults to one. The -l option is deprecated since the POSIX standard specifies -L instead. -n max-args, --max-args=max-args Use at most max-args arguments per command line. Fewer than max-args arguments will be used if the size (see the -s option) is exceeded, unless the -x option is given, in which case xargs will exit. -P max-procs, --max-procs=max-procs Run up to max-procs processes at a time; the default is 1. If max-procs is 0, xargs will run as many processes as possible at a time. Use the -n option or the -L option with -P; otherwise chances are that only one exec will be done. While xargs is running, you can send its process a SIGUSR1 signal to increase the number of commands to run simultaneously, or a SIGUSR2 to decrease the number. You cannot increase it above an implementation-defined limit (which is shown with --show-limits). You cannot decrease it below 1. xargs never terminates its commands; when asked to decrease, it merely waits for more than one existing command to terminate before starting another. Please note that it is up to the called processes to properly manage parallel access to shared resources. For example, if more than one of them tries to print to stdout, the output will be produced in an indeterminate order (and very likely mixed up) unless the processes collaborate in some way to prevent this. Using some kind of locking scheme is one way to prevent such problems. In general, using a locking scheme will help ensure correct output but reduce performance. If you don't want to tolerate the performance difference, simply arrange for each process to produce a separate output file (or otherwise use separate resources). -o, --open-tty Reopen stdin as /dev/tty in the child process before executing the command. This is useful if you want xargs to run an interactive application. -p, --interactive Prompt the user about whether to run each command line and read a line from the terminal. Only run the command line if the response starts with `y' or `Y'. Implies -t. --process-slot-var=name Set the environment variable name to a unique value in each running child process. Values are reused once child processes exit. This can be used in a rudimentary load distribution scheme, for example. -r, --no-run-if-empty If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This option is a GNU extension. -s max-chars, --max-chars=max-chars Use at most max-chars characters per command line, including the command and initial-arguments and the terminating nulls at the ends of the argument strings. The largest allowed value is system-dependent, and is calculated as the argument length limit for exec, less the size of your environment, less 2048 bytes of headroom. If this value is more than 128 KiB, 128 KiB is used as the default value; otherwise, the default value is the maximum. 1 KiB is 1024 bytes. xargs automatically adapts to tighter constraints. --show-limits Display the limits on the command-line length which are imposed by the operating system, xargs' choice of buffer size and the -s option. Pipe the input from /dev/null (and perhaps specify --no-run-if-empty) if you don't want xargs to do anything. -t, --verbose Print the command line on the standard error output before executing it. -x, --exit Exit if the size (see the -s option) is exceeded. -- Delimit the option list. Later arguments, if any, are treated as operands even if they begin with -. For example, xargs -- --help runs the command --help (found in PATH) instead of printing the usage text, and xargs -- --mycommand runs the command --mycommand instead of rejecting this as unrecognized option. --help Print a summary of the options to xargs and exit. --version Print the version number of xargs and exit. The options --max-lines (-L, -l), --replace (-I, -i) and --max- args (-n) are mutually exclusive. If some of them are specified at the same time, then xargs will generally use the option specified last on the command line, i.e., it will reset the value of the offending option (given before) to its default value. Additionally, xargs will issue a warning diagnostic on stderr. The exception to this rule is that the special max-args value 1 ('-n1') is ignored after the --replace option and its aliases -I and -i, because it would not actually conflict. EXAMPLES top find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing spaces or newlines are correctly handled. find /tmp -depth -name core -type f -delete Find files named core in or below the directory /tmp and delete them, but more efficiently than in the previous example (because we avoid the need to use fork(2) and exec(2) to launch rm and we don't need the extra xargs process). cut -d: -f1 < /etc/passwd | sort | xargs echo Generates a compact listing of all the users on the system. EXIT STATUS top xargs exits with the following status: 0 if it succeeds 123 if any invocation of the command exited with status 1125 124 if the command exited with status 255 125 if the command is killed by a signal 126 if the command cannot be run 127 if the command is not found 1 if some other error occurred. Exit codes greater than 128 are used by the shell to indicate that a program died due to a fatal signal. STANDARDS CONFORMANCE top As of GNU xargs version 4.2.9, the default behaviour of xargs is not to have a logical end-of-file marker. POSIX (IEEE Std 1003.1, 2004 Edition) allows this. The -l and -i options appear in the 1997 version of the POSIX standard, but do not appear in the 2004 version of the standard. Therefore you should use -L and -I instead, respectively. The -o option is an extension to the POSIX standard for better compatibility with BSD. The POSIX standard allows implementations to have a limit on the size of arguments to the exec functions. This limit could be as low as 4096 bytes including the size of the environment. For scripts to be portable, they must not rely on a larger value. However, I know of no implementation whose actual limit is that small. The --show-limits option can be used to discover the actual limits in force on the current system. HISTORY top The xargs program was invented by Herb Gellis at Bell Labs. See the Texinfo manual for findutils, Finding Files, for more information. BUGS top It is not possible for xargs to be used securely, since there will always be a time gap between the production of the list of input files and their use in the commands that xargs issues. If other users have access to the system, they can manipulate the filesystem during this time window to force the action of the commands xargs runs to apply to files that you didn't intend. For a more detailed discussion of this and related problems, please refer to the ``Security Considerations'' chapter in the findutils Texinfo documentation. The -execdir option of find can often be used as a more secure alternative. When you use the -I option, each line read from the input is buffered internally. This means that there is an upper limit on the length of input line that xargs will accept when used with the -I option. To work around this limitation, you can use the -s option to increase the amount of buffer space that xargs uses, and you can also use an extra invocation of xargs to ensure that very long lines do not occur. For example: somecommand | xargs -s 50000 echo | xargs -I '{}' -s 100000 rm '{}' Here, the first invocation of xargs has no input line length limit because it doesn't use the -i option. The second invocation of xargs does have such a limit, but we have ensured that it never encounters a line which is longer than it can handle. This is not an ideal solution. Instead, the -i option should not impose a line length limit, which is why this discussion appears in the BUGS section. The problem doesn't occur with the output of find(1) because it emits just one filename per line. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 19902023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top find(1), kill(1), locate(1), updatedb(1), fork(2), execvp(3), locatedb(5), signal(7) Full documentation <https://www.gnu.org/software/findutils/xargs> or available locally via: info xargs COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org XARGS(1) Pages that refer to this page: dpkg-name(1), find(1), grep(1), locate(1), updatedb(1), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all directories in the TBD directory that were modified more than 1 day ago Bash Command:<START>find /TBD -mtime +1 -type d | xargs rm -f -r<END>

Delete all directories under '.cache/chromium/Default/Cache' directory tree that are at least 1 level deep and are bigger than 100 MB in size

find .cache/chromium/Default/Cache/ -mindepth 1 -type d -size +100M -delete

['find']

Output a Bash command to accomplish the following task. Task: Delete all directories under '.cache/chromium/Default/Cache' directory tree that are at least 1 level deep and are bigger than 100 MB in size Bash Command:<START>find .cache/chromium/Default/Cache/ -mindepth 1 -type d -size +100M -delete<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n Task: Delete all directories under '.cache/chromium/Default/Cache' directory tree that are at least 1 level deep and are bigger than 100 MB in size Bash Command:<START>find .cache/chromium/Default/Cache/ -mindepth 1 -type d -size +100M -delete<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all directories under '.cache/chromium/Default/Cache' directory tree that are at least 1 level deep and are bigger than 100 MB in size Bash Command:<START>find .cache/chromium/Default/Cache/ -mindepth 1 -type d -size +100M -delete<END>

Delete all directories under '.cache/chromium/Default/Cache/' directory tree that are bigger than 100MB and are at least 1 level deep

find .cache/chromium/Default/Cache/ -mindepth 1 -type d -size +100M -exec rm -rf {} \;

['find', 'rm']

Output a Bash command to accomplish the following task. Task: Delete all directories under '.cache/chromium/Default/Cache/' directory tree that are bigger than 100MB and are at least 1 level deep Bash Command:<START>find .cache/chromium/Default/Cache/ -mindepth 1 -type d -size +100M -exec rm -rf {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # rm\n\n> Remove files or directories.\n> See also: `rmdir`.\n> More information: <https://www.gnu.org/software/coreutils/rm>.\n\n- Remove specific files:\n\n`rm {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files ignoring nonexistent ones:\n\n`rm --force {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files interactively prompting before each removal:\n\n`rm --interactive {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files printing info about each removal:\n\n`rm --verbose {{path/to/file1 path/to/file2 ...}}`\n\n- Remove specific files and directories recursively:\n\n`rm --recursive {{path/to/file_or_directory1 path/to/file_or_directory2 ...}}`\n Task: Delete all directories under '.cache/chromium/Default/Cache/' directory tree that are bigger than 100MB and are at least 1 level deep Bash Command:<START>find .cache/chromium/Default/Cache/ -mindepth 1 -type d -size +100M -exec rm -rf {} \;<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. rm(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training rm(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON RM(1) User Commands RM(1) NAME top rm - remove files or directories SYNOPSIS top rm [OPTION]... [FILE]... DESCRIPTION top This manual page documents the GNU version of rm. rm removes each specified file. By default, it does not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. OPTIONS top Remove (unlink) the FILE(s). -f, --force ignore nonexistent files and arguments, never prompt -i prompt before every removal -I prompt once before removing more than three files, or when removing recursively; less intrusive than -i, while still giving protection against most mistakes --interactive[=WHEN] prompt according to WHEN: never, once (-I), or always (-i); without WHEN, prompt always --one-file-system when removing a hierarchy recursively, skip any directory that is on a file system different from that of the corresponding command line argument --no-preserve-root do not treat '/' specially --preserve-root[=all] do not remove '/' (default); with 'all', reject any command line argument on a separate device from its parent -r, -R, --recursive remove directories and their contents recursively -d, --dir remove empty directories -v, --verbose explain what is being done --help display this help and exit --version output version information and exit By default, rm does not remove directories. Use the --recursive (-r or -R) option to remove each listed directory, too, along with all of its contents. To remove a file whose name starts with a '-', for example '-foo', use one of these commands: rm -- -foo rm ./-foo Note that if you use rm to remove a file, it might be possible to recover some of its contents, given sufficient expertise and/or time. For greater assurance that the contents are truly unrecoverable, consider using shred(1). AUTHOR top Written by Paul Rubin, David MacKenzie, Richard M. Stallman, and Jim Meyering. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top unlink(1), unlink(2), chattr(1), shred(1) Full documentation <https://www.gnu.org/software/coreutils/rm> or available locally via: info '(coreutils) rm invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 RM(1) Pages that refer to this page: rmdir(2), unlink(2), remove(3), mq_overview(7), symlink(7), debugfs(8), lsof(8) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all directories under '.cache/chromium/Default/Cache/' directory tree that are bigger than 100MB and are at least 1 level deep Bash Command:<START>find .cache/chromium/Default/Cache/ -mindepth 1 -type d -size +100M -exec rm -rf {} \;<END>

Delete all empty directories in minimum 1 level down the directory 'directory'

find directory -mindepth 1 -type d -empty -delete

['find']

Output a Bash command to accomplish the following task. Task: Delete all empty directories in minimum 1 level down the directory 'directory' Bash Command:<START>find directory -mindepth 1 -type d -empty -delete<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n Task: Delete all empty directories in minimum 1 level down the directory 'directory' Bash Command:<START>find directory -mindepth 1 -type d -empty -delete<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all empty directories in minimum 1 level down the directory 'directory' Bash Command:<START>find directory -mindepth 1 -type d -empty -delete<END>

Delete all empty directories in minimum 2 levels down the root directory

find root -mindepth 2 -type d -empty -delete

['find']

Output a Bash command to accomplish the following task. Task: Delete all empty directories in minimum 2 levels down the root directory Bash Command:<START>find root -mindepth 2 -type d -empty -delete<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n Task: Delete all empty directories in minimum 2 levels down the root directory Bash Command:<START>find root -mindepth 2 -type d -empty -delete<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all empty directories in minimum 2 levels down the root directory Bash Command:<START>find root -mindepth 2 -type d -empty -delete<END>

Delete all empty directories in the "test" directory tree

find test -depth -type d -empty -delete

['find', 'test']

Output a Bash command to accomplish the following task. Task: Delete all empty directories in the "test" directory tree Bash Command:<START>find test -depth -type d -empty -delete<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: # find\n\n> Find files or directories under a directory tree, recursively.\n> More information: <https://manned.org/find>.\n\n- Find files by extension:\n\n`find {{root_path}} -name '{{*.ext}}'`\n\n- Find files matching multiple path/name patterns:\n\n`find {{root_path}} -path '{{**/path/**/*.ext}}' -or -name '{{*pattern*}}'`\n\n- Find directories matching a given name, in case-insensitive mode:\n\n`find {{root_path}} -type d -iname '{{*lib*}}'`\n\n- Find files matching a given pattern, excluding specific paths:\n\n`find {{root_path}} -name '{{*.py}}' -not -path '{{*/site-packages/*}}'`\n\n- Find files matching a given size range, limiting the recursive depth to "1":\n\n`find {{root_path}} -maxdepth 1 -size {{+500k}} -size {{-10M}}`\n\n- Run a command for each file (use `{}` within the command to access the filename):\n\n`find {{root_path}} -name '{{*.ext}}' -exec {{wc -l}} {} \;`\n\n- Find all files modified today and pass the results to a single command as arguments:\n\n`find {{root_path}} -daystart -mtime {{-1}} -exec {{tar -cvf archive.tar}} {} \+`\n\n- Find empty (0 byte) files and delete them:\n\n`find {{root_path}} -type {{f}} -empty -delete`\n # test\n\n> Check file types and compare values.\n> Returns 0 if the condition evaluates to true, 1 if it evaluates to false.\n> More information: <https://www.gnu.org/software/coreutils/test>.\n\n- Test if a given variable is equal to a given string:\n\n`test "{{$MY_VAR}}" = "{{/bin/zsh}}"`\n\n- Test if a given variable is empty:\n\n`test -z "{{$GIT_BRANCH}}"`\n\n- Test if a file exists:\n\n`test -f "{{path/to/file_or_directory}}"`\n\n- Test if a directory does not exist:\n\n`test ! -d "{{path/to/directory}}"`\n\n- If A is true, then do B, or C in the case of an error (notice that C may run even if A fails):\n\n`test {{condition}} && {{echo "true"}} || {{echo "false"}}`\n Task: Delete all empty directories in the "test" directory tree Bash Command:<START>find test -depth -type d -empty -delete<END>

Use the provided context to output a Bash command that accomplishes the following task. Context: find(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training find(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXPRESSION | UNUSUAL FILENAMES | STANDARDS CONFORMANCE | ENVIRONMENT VARIABLES | EXAMPLES | EXIT STATUS | HISTORY | COMPATIBILITY | NON-BUGS | BUGS | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON FIND(1) General Commands Manual FIND(1) NAME top find - search for files in a directory hierarchy SYNOPSIS top find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression] DESCRIPTION top This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information. OPTIONS top The -H, -L and -P options control the treatment of symbolic links. Command-line arguments following these are taken to be names of files or directories to be examined, up to the first argument that begins with `-', or the argument `(' or `!'. That argument and any following arguments are taken to be the expression describing what is to be searched for. If no paths are given, the current directory is used. If no expression is given, the expression -print is used (but you should probably consider using -print0 instead, anyway). This manual page talks about `options' within the expression list. These options control the behaviour of find but are specified immediately after the last path name. The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all. A double dash -- could theoretically be used to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-'). Now, if a path argument would start with a `-', then find would treat it as expression argument instead. Thus, to ensure that all start points are taken as such, and especially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer to prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'. Alternatively, it is generally safe though non-portable to use the GNU option -files0-from to pass arbitrary starting points to find. -P Never follow symbolic links. This is the default behaviour. When find examines or prints information about files, and the file is a symbolic link, the information used shall be taken from the properties of the symbolic link itself. -L Follow symbolic links. When find examines or prints information about files, the information used shall be taken from the properties of the file to which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which the link points). Use of this option implies -noleaf. If you later use the -P option, -noleaf will still be in effect. If -L is in effect and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched. When the -L option is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself (unless the symbolic link is broken). Actions that can cause symbolic links to become broken while find is executing (for example -delete) can give rise to confusing behaviour. Using -L causes the -lname and -ilname predicates always to return false. -H Do not follow symbolic links, except while processing the command line arguments. When find examines or prints information about files, the information used shall be taken from the properties of the symbolic link itself. The only exception to this behaviour is when a file specified on the command line is a symbolic link, and the link can be resolved. For that situation, the information used is taken from whatever the link points to (that is, the link is followed). The information about the link itself is used as a fallback if the file pointed to by the symbolic link cannot be examined. If -H is in effect and one of the paths specified on the command line is a symbolic link to a directory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this). If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect. Since it is the default, the -P option should be considered to be in effect unless either -H or -L is specified. GNU find frequently stats files during the processing of the command line itself, before any searching has begun. These options also affect how those arguments are processed. Specifically, there are a number of tests that compare files listed on the command line against a file we are currently considering. In each case, the file specified on the command line will have been examined and some of its properties will have been saved. If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for the comparison will be taken from the properties of the symbolic link. Otherwise, it will be taken from the properties of the file the link points to. If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties of the link itself will be used. When the -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken from the file to which the symbolic link points. The same consideration applies to -newerXY, -anewer and -cnewer. The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is, any symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not). -D debugopts Print diagnostic information; this can be helpful to diagnose problems with why find is not doing what you want. The list of debug options should be comma separated. Compatibility of the debug options is not guaranteed between releases of findutils. For a complete list of valid debug options, see the output of find -D help. Valid debug options include exec Show diagnostic information relating to -exec, -execdir, -ok and -okdir opt Prints diagnostic information relating to the optimisation of the expression tree; see the -O option. rates Prints a summary indicating how often each predicate succeeded or failed. search Navigate the directory tree verbosely. stat Print messages as files are examined with the stat and lstat system calls. The find program tries to minimise such calls. tree Show the expression tree in its original and optimised form. all Enable all of the other debug options (but help). help Explain the debugging options. -Olevel Enables query optimisation. The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates with side effects are not reordered relative to each other. The optimisations performed at each optimisation level are as follows. 0 Equivalent to optimisation level 1. 1 This is the default optimisation level and corresponds to the traditional behaviour. Expressions are reordered so that tests based only on the names of files (for example -name and -regex) are performed first. 2 Any -type or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode. On many modern versions of Unix, file types are returned by readdir() and so these predicates are faster to evaluate than predicates which need to stat the file first. If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false. 3 At this optimisation level, the full cost-based query optimiser is enabled. The order of tests is modified so that cheap (i.e. fast) tests are performed first and more expensive ones are performed later, if necessary. Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not. For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier. The cost-based optimiser has a fixed idea of how likely any given test is to succeed. In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c). The cost-based optimiser is currently being evaluated. If it does not actually improve the performance of find, it will be removed again. Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time. However, the default behaviour (i.e. optimisation level 1) will not be changed in the 4.3.x release series. The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same. EXPRESSION top The part of the command line after the list of starting points is the expression. This is a kind of query specification describing how we match files and what we do with the files that were matched. An expression is composed of a sequence of things: Tests Tests return a true or false value, usually on the basis of some property of a file we are considering. The -empty test for example is true only when the current file is empty. Actions Actions have side effects (such as printing something on the standard output) and return either true or false, usually based on whether or not they are successful. The -print action for example prints the name of the current file on the standard output. Global options Global options affect the operation of tests and actions specified on any part of the command line. Global options always return true. The -depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them. Positional options always return true. The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line. Operators Operators join together the other items within the expression. They include for example -o (meaning logical OR) and -a (meaning logical AND). Where an operator is missing, -a is assumed. The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune or -quit. Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -fprint, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth). POSITIONAL OPTIONS Positional options always return true. They affect only tests occurring later on the command line. -daystart Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago. This option only affects tests which appear later on the command line. -follow Deprecated; use the -L option instead. Dereference symbolic links. Implies -noleaf. The -follow option affects only those tests which appear after it on the command line. Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links. The same consideration applies to -newerXY, -anewer and -cnewer. Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself. Using -follow causes the -lname and -ilname predicates always to return false. -regextype type Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line. To see which regular expression types are known, use -regextype help. The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression. -warn, -nowarn Turn warning messages on or off. These warnings apply only to the command line usage, not to any conditions that find might encounter when it searches directories. The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise. If a warning message relating to command-line usage is produced, the exit status of find is not affected. If the POSIXLY_CORRECT environment variable is set, and -warn is also used, it is not specified which, if any, warnings will be active. GLOBAL OPTIONS Global options always return true. Global options take effect even for tests which occur earlier on the command line. To prevent confusion, global options should be specified on the command-line after the list of start points, just before the first test, positional option or action. If you specify a global option in some other place, find will issue a warning message explaining that this can be confusing. The global options occur after the list of start points, and so are not the same kind of option as -L, for example. -d A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD. -depth Process each directory's contents before the directory itself. The -delete action also implies -depth. -files0-from file Read the starting points from file instead of getting them on the command line. In contrast to the known limitations of passing starting points via arguments on the command line, namely the limitation of the amount of file names, and the inherent ambiguity of file names clashing with option names, using this option allows to safely pass an arbitrary number of starting points to find. Using this option and passing starting points on the command line is mutually exclusive, and is therefore not allowed at the same time. The file argument is mandatory. One can use -files0-from - to read the list of starting points from the standard input stream, and e.g. from a pipe. In this case, the actions -ok and -okdir are not allowed, because they would obviously interfere with reading from standard input in order to get a user confirmation. The starting points in file have to be separated by ASCII NUL characters. Two consecutive NUL characters, i.e., a starting point with a Zero-length file name is not allowed and will lead to an error diagnostic followed by a non- Zero exit code later. In the case the given file is empty, find does not process any starting point and therefore will exit immediately after parsing the program arguments. This is unlike the standard invocation where find assumes the current directory as starting point if no path argument is passed. The processing of the starting points is otherwise as usual, e.g. find will recurse into subdirectories unless otherwise prevented. To process only the starting points, one can additionally pass -maxdepth 0. Further notes: if a file is listed more than once in the input file, it is unspecified whether it is visited more than once. If the file is mutated during the operation of find, the result is unspecified as well. Finally, the seek position within the named file at the time find exits, be it with -quit or in any other way, is also unspecified. By "unspecified" here is meant that it may or may not work or do any specific thing, and that the behavior may change from platform to platform, or from findutils release to release. -help, --help Print a summary of the command-line usage of find and exit. -ignore_readdir_race Normally, find will emit an error message when it fails to stat a file. If you give this option and a file is deleted between the time find reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued. This also applies to files or directories whose names are given on the command line. This option takes effect at the time the command line is read, which means that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that, you will need to issue two find commands instead, one with the option and one without it). Furthermore, find with the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true. -maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the starting-points. Using -maxdepth 0 means only apply the tests and actions to the starting- points themselves. -mindepth levels Do not apply any tests or actions at levels less than levels (a non-negative integer). Using -mindepth 1 means process all files except the starting-points. -mount Don't descend directories on other filesystems. An alternate name for -xdev, for compatibility with some other versions of find. -noignore_readdir_race Turns off the effect of -ignore_readdir_race. -noleaf Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry. Additionally, its subdirectories (if any) each have a `..' entry linked to that directory. When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed. -version, --version Print the find version number and exit. -xdev Don't descend directories on other filesystems. TESTS Some tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line. When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -follow, but the reference file is only examined once, at the time the command line is parsed. If the reference file cannot be examined (for example, the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status. A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as +n for greater than n, -n for less than n, n for exactly n. Supported tests: -amin n File was last accessed less than, more than or exactly n minutes ago. -anewer reference Time of the last access of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -atime n File was last accessed less than, more than or exactly n*24 hours ago. When find figures out how many 24-hour periods ago the file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago. -cmin n File's status was last changed less than, more than or exactly n minutes ago. -cnewer reference Time of the last status change of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -ctime n File's status was last changed less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file status change times. -empty File is empty and is either a regular file or a directory. -executable Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. Because this test is based only on the result of the access(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed. -false Always false. -fstype type File is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can use -printf with the %F directive to see the types of your filesystems. -gid n File's numeric group ID is less than, more than or exactly n. -group gname File belongs to group gname (numeric group ID allowed). -ilname pattern Like -lname, but the match is case insensitive. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -iname pattern Like -name, but the match is case insensitive. For example, the patterns `fo*' and `F??' match the file names `Foo', `FOO', `foo', `fOo', etc. The pattern `*foo*` will also match a file called '.foobar'. -inum n File has inode number smaller than, greater than or exactly n. It is normally easier to use the -samefile test instead. -ipath pattern Like -path. but the match is case insensitive. -iregex pattern Like -regex, but the match is case insensitive. -iwholename pattern See -ipath. This alternative is less portable than -ipath. -links n File has less than, more than or exactly n hard links. -lname pattern File is a symbolic link whose contents match shell pattern pattern. The metacharacters do not treat `/' or `.' specially. If the -L option or the -follow option is in effect, this test returns false unless the symbolic link is broken. -mmin n File's data was last modified less than, more than or exactly n minutes ago. -mtime n File's data was last modified less than, more than or exactly n*24 hours ago. See the comments for -atime to understand how rounding affects the interpretation of file modification times. -name pattern Base of file name (the path with the leading directories removed) matches shell pattern pattern. Because the leading directories of the file names are removed, the pattern should not include a slash, because `-name a/b' will never match anything (and you probably want to use -path instead). An exception to this is when using only a slash as pattern (`-name /'), because that is a valid string for matching the root directory "/" (because the base name of "/" is "/"). A warning is issued if you try to pass a pattern containing a - but not consisting solely of one - slash, unless the environment variable POSIXLY_CORRECT is set or the option -nowarn is used. To ignore a directory and the files under it, use -prune rather than checking every file in the tree; see an example in the description of that action. Braces are not recognised as being special, despite the fact that some shells including Bash imbue braces with a special meaning in shell patterns. The filename matching is performed with the use of the fnmatch(3) library function. Don't forget to enclose the pattern in quotes in order to protect it from expansion by the shell. -newer reference Time of the last data modification of the current file is more recent than that of the last data modification of the reference file. If reference is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always used. -newerXY reference Succeeds if timestamp X of the file being considered is newer than timestamp Y of the file reference. The letters X and Y can be any of the following letters: a The access time of the file reference B The birth time of the file reference c The inode status change time of reference m The modification time of the file reference t reference is interpreted directly as a time Some combinations are invalid; for example, it is invalid for X to be t. Some combinations are not implemented on all systems; for example B is not supported on all systems. If an invalid or unsupported combination of XY is specified, a fatal error results. Time specifications are interpreted as for the argument to the -d option of GNU date. If you try to use the birth time of a reference file, and the birth time cannot be determined, a fatal error message results. If you specify a test which refers to the birth time of files being examined, this test will fail for any files where the birth time is unknown. -nogroup No group corresponds to file's numeric group ID. -nouser No user corresponds to file's numeric user ID. -path pattern File name matches shell pattern pattern. The metacharacters do not treat `/' or `.' specially; so, for example, find . -path "./sr*sc" will print an entry for a directory called ./src/misc (if one exists). To ignore a whole directory tree, use -prune rather than checking every file in the tree. Note that the pattern match test applies to the whole file name, starting from one of the start points named on the command line. It would only make sense to use an absolute path name here if the relevant start point is also an absolute path. This means that this command will never match anything: find bar -path /foo/bar/myfile -print Find compares the -path argument with the concatenation of a directory name and the base name of the file it's examining. Since the concatenation will never end with a slash, -path arguments ending in a slash will match nothing (except perhaps a start point specified on the command line). The predicate -path is also supported by HP-UX find and is part of the POSIX 2008 standard. -perm mode File's permission bits are exactly mode (octal or symbolic). Since an exact match is required, if you want to use this form for symbolic modes, you may have to specify a rather complex mode string. For example `-perm g=w' will only match files which have mode 0020 (that is, ones for which group write permission is the only permission set). It is more likely that you will want to use the `/' or `-' forms, for example `-perm -g=w', which matches any file with group write permission. See the EXAMPLES section for some illustrative examples. -perm -mode All of the permission bits mode are set for the file. Symbolic modes are accepted in this form, and this is usually the way in which you would want to use them. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. -perm /mode Any of the permission bits mode are set for the file. Symbolic modes are accepted in this form. You must specify `u', `g' or `o' if you use a symbolic mode. See the EXAMPLES section for some illustrative examples. If no permission bits in mode are set, this test matches any file (the idea here is to be consistent with the behaviour of -perm -000). -perm +mode This is no longer supported (and has been deprecated since 2005). Use -perm /mode instead. -readable Matches files which are readable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -regex pattern File name matches regular expression pattern. This is a match on the whole path, not a search. For example, to match a file named ./fubar3, you can use the regular expression `.*bar.' or `.*b.*3', but not `f.*r3'. The regular expressions understood by find are by default Emacs Regular Expressions (except that `.' matches newline), but this can be changed with the -regextype option. -samefile name File refers to the same inode as name. When -L is in effect, this can include symbolic links. -size n[cwbkMG] File uses less than, more than or exactly n units of space, rounding up. The following suffixes can be used: `b' for 512-byte blocks (this is the default if no suffix is used) `c' for bytes `w' for two-byte words `k' for kibibytes (KiB, units of 1024 bytes) `M' for mebibytes (MiB, units of 1024 * 1024 = 1048576 bytes) `G' for gibibytes (GiB, units of 1024 * 1024 * 1024 = 1073741824 bytes) The size is simply the st_size member of the struct stat populated by the lstat (or stat) system call, rounded up as shown above. In other words, it's consistent with the result you get for ls -l. Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently. The `b' suffix always denotes 512-byte blocks and never 1024-byte blocks, which is different to the behaviour of -ls. The + and - prefixes signify greater than and less than, as usual; i.e., an exact size of n units does not match. Bear in mind that the size is rounded up to the next unit. Therefore -size -1M is not equivalent to -size -1048576c. The former only matches empty files, the latter matches files from 0 to 1,048,575 bytes. -true Always true. -type c File is of type c: b block (buffered) special c character (unbuffered) special d directory p named pipe (FIFO) f regular file l symbolic link; this is never true if the -L option or the -follow option is in effect, unless the symbolic link is broken. If you want to search for symbolic links when -L is in effect, use -xtype. s socket D door (Solaris) To search for more than one type at once, you can supply the combined list of type letters separated by a comma `,' (GNU extension). -uid n File's numeric user ID is less than, more than or exactly n. -used n File was last accessed less than, more than or exactly n days after its status was last changed. -user uname File is owned by user uname (numeric user ID allowed). -wholename pattern See -path. This alternative is less portable than -path. -writable Matches files which are writable by the current user. This takes into account access control lists and other permissions artefacts which the -perm test ignores. This test makes use of the access(2) system call, and so can be fooled by NFS servers which do UID mapping (or root- squashing), since many systems implement access(2) in the client's kernel and so cannot make use of the UID mapping information held on the server. -xtype c The same as -type unless the file is a symbolic link. For symbolic links: if the -H or -P option was specified, true if the file is a link to a file of type c; if the -L option has been given, true if c is `l'. In other words, for symbolic links, -xtype checks the type of the file that -type does not check. -context pattern (SELinux only) Security context of the file matches glob pattern. ACTIONS -delete Delete files or directories; true if removal succeeded. If the removal failed, an error message is issued and find's exit status will be nonzero (when it eventually exits). Warning: Don't forget that find evaluates the command line as an expression, so putting -delete first will make find try to delete everything below the starting points you specified. The use of the -delete action on the command line automatically turns on the -depth option. As in turn -depth makes -prune ineffective, the -delete action cannot usefully be combined with -prune. Often, the user might want to test a find command line with -print prior to adding -delete for the actual removal run. To avoid surprising results, it is usually best to remember to use -depth explicitly during those earlier test runs. The -delete action will fail to remove a directory unless it is empty. Together with the -ignore_readdir_race option, find will ignore errors of the -delete action in the case the file has disappeared since the parent directory was read: it will not output an error diagnostic, not change the exit code to nonzero, and the return code of the -delete action will be true. -exec command ; Execute command; true if 0 status is returned. All following arguments to find are taken to be arguments to the command until an argument consisting of `;' is encountered. The string `{}' is replaced by the current file name being processed everywhere it occurs in the arguments to the command, not just in arguments where it is alone, as in some versions of find. Both of these constructions might need to be escaped (with a `\') or quoted to protect them from expansion by the shell. See the EXAMPLES section for examples of the use of the -exec option. The specified command is run once for each matched file. The command is executed in the starting directory. There are unavoidable security problems surrounding use of the -exec action; you should use the -execdir option instead. -exec command {} + This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end; the total number of invocations of the command will be much less than the number of matched files. The command line is built in much the same way that xargs builds its command lines. Only one instance of `{}' is allowed within the command, and it must appear at the end, immediately before the `+'; it needs to be escaped (with a `\') or quoted to protect it from interpretation by the shell. The command is executed in the starting directory. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. For this reason -exec my- command ... {} + -quit may not result in my-command actually being run. This variant of -exec always returns true. -execdir command ; -execdir command {} + Like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find. As with -exec, the {} should be quoted if find is being invoked from a shell. This a much more secure method for invoking commands, as it avoids race conditions during resolution of the paths to the matched files. As with the -exec action, the `+' form of -execdir will build a command line to process more than one matched file, but any given invocation of command will only list files that exist in the same subdirectory. If you use this option, you must ensure that your PATH environment variable does not reference `.'; otherwise, an attacker can run any commands they like by leaving an appropriately-named file in a directory in which you will run -execdir. The same applies to having entries in PATH which are empty or which are not absolute directory names. If any invocation with the `+' form returns a non-zero value as exit status, then find returns a non-zero exit status. If find encounters an error, this can sometimes cause an immediate exit, so some pending commands may not be run at all. The result of the action depends on whether the + or the ; variant is being used; -execdir command {} + always returns true, while -execdir command {} ; returns true only if command returns 0. -fls file True; like -ls but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint file True; print the full file name into file file. If file does not exist when find is run, it is created; if it does exist, it is truncated. The file names /dev/stdout and /dev/stderr are handled specially; they refer to the standard output and standard error output, respectively. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprint0 file True; like -print0 but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -fprintf file format True; like -printf but write to file like -fprint. The output file is always created, even if the predicate is never matched. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ls True; list current file in ls -dils format on standard output. The block counts are of 1 KB blocks, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -ok command ; Like -exec but ask the user first. If the user agrees, run the command. Otherwise just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. The response to the prompt is matched against a pair of regular expressions to determine if it is an affirmative or negative response. This regular expression is obtained from the system if the POSIXLY_CORRECT environment variable is set, or otherwise from find's message translations. If the system has no suitable definition, find's own definition will be used. In either case, the interpretation of the regular expression itself will be affected by the environment variables LC_CTYPE (character classes) and LC_COLLATE (character ranges and equivalence classes). -okdir command ; Like -execdir but ask the user first in the same way as for -ok. If the user does not agree, just return false. If the command is run, its standard input is redirected from /dev/null. This action may not be specified together with the -files0-from option. -print True; print the full file name on the standard output, followed by a newline. If you are piping the output of find into another program and there is the faintest possibility that the files which you are searching for might contain a newline, then you should seriously consider using the -print0 option instead of -print. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -print0 True; print the full file name on the standard output, followed by a null character (instead of the newline character that -print uses). This allows file names that contain newlines or other types of white space to be correctly interpreted by programs that process the find output. This option corresponds to the -0 option of xargs. -printf format True; print format on the standard output, interpreting `\' escapes and `%' directives. Field widths and precisions can be specified as with the printf(3) C function. Please note that many of the fields are printed as %s rather than %d, and this may mean that flags don't work as you might expect. This also means that the `-' flag does work (it forces fields to be left-aligned). Unlike -print, -printf does not add a newline at the end of the string. The escapes and directives are: \a Alarm bell. \b Backspace. \c Stop printing from this format immediately and flush the output. \f Form feed. \n Newline. \r Carriage return. \t Horizontal tab. \v Vertical tab. \0 ASCII NUL. \\ A literal backslash (`\'). \NNN The character whose ASCII code is NNN (octal). A `\' character followed by any other character is treated as an ordinary character, so they both are printed. %% A literal percent sign. %a File's last access time in the format returned by the C ctime(3) function. %Ak File's last access time in the format specified by k, which is either `@' or a directive for the C strftime(3) function. The following shows an incomplete list of possible values for k. Please refer to the documentation of strftime(3) for the full list. Some of the conversion specification characters might not be available on all systems, due to differences in the implementation of the strftime(3) library function. @ seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Time fields: H hour (00..23) I hour (01..12) k hour ( 0..23) l hour ( 1..12) M minute (00..59) p locale's AM or PM r time, 12-hour (hh:mm:ss [AP]M) S Second (00.00 .. 61.00). There is a fractional part. T time, 24-hour (hh:mm:ss.xxxxxxxxxx) + Date and time, separated by `+', for example `2004-04-28+22:22:05.0'. This is a GNU extension. The time is given in the current timezone (which may be affected by setting the TZ environment variable). The seconds field includes a fractional part. X locale's time representation (H:M:S). The seconds field includes a fractional part. Z time zone (e.g., EDT), or nothing if no time zone is determinable Date fields: a locale's abbreviated weekday name (Sun..Sat) A locale's full weekday name, variable length (Sunday..Saturday) b locale's abbreviated month name (Jan..Dec) B locale's full month name, variable length (January..December) c locale's date and time (Sat Nov 04 12:02:33 EST 1989). The format is the same as for ctime(3) and so to preserve compatibility with that format, there is no fractional part in the seconds field. d day of month (01..31) D date (mm/dd/yy) F date (yyyy-mm-dd) h same as b j day of year (001..366) m month (01..12) U week number of year with Sunday as first day of week (00..53) w day of week (0..6) W week number of year with Monday as first day of week (00..53) x locale's date representation (mm/dd/yy) y last two digits of year (00..99) Y year (1970...) %b The amount of disk space used for this file in 512-byte blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/512, but it can also be smaller if the file is a sparse file. %Bk File's birth time, i.e., its creation time, in the format specified by k, which is the same as for %A. This directive produces an empty string if the underlying operating system or filesystem does not support birth times. %c File's last status change time in the format returned by the C ctime(3) function. %Ck File's last status change time in the format specified by k, which is the same as for %A. %d File's depth in the directory tree; 0 means the file is a starting-point. %D The device number on which the file exists (the st_dev field of struct stat), in decimal. %f Print the basename; the file's name with any leading directories removed (only the last element). For /, the result is `/'. See the EXAMPLES section for an example. %F Type of the filesystem the file is on; this value can be used for -fstype. %g File's group name, or numeric group ID if the group has no name. %G File's numeric group ID. %h Dirname; the Leading directories of the file's name (all but the last element). If the file name contains no slashes (since it is in the current directory) the %h specifier expands to `.'. For files which are themselves directories and contain a slash (including /), %h expands to the empty string. See the EXAMPLES section for an example. %H Starting-point under which file was found. %i File's inode number (in decimal). %k The amount of disk space used for this file in 1 KB blocks. Since disk space is allocated in multiples of the filesystem block size this is usually greater than %s/1024, but it can also be smaller if the file is a sparse file. %l Object of symbolic link (empty string if file is not a symbolic link). %m File's permission bits (in octal). This option uses the `traditional' numbers which most Unix implementations use, but if your particular implementation uses an unusual ordering of octal permissions bits, you will see a difference between the actual value of the file's mode and the output of %m. Normally you will want to have a leading zero on this number, and to do this, you should use the # flag (as in, for example, `%#m'). %M File's permissions (in symbolic form, as for ls). This directive is supported in findutils 4.2.5 and later. %n Number of hard links to file. %p File's name. %P File's name with the name of the starting-point under which it was found removed. %s File's size in bytes. %S File's sparseness. This is calculated as (BLOCKSIZE*st_blocks / st_size). The exact value you will get for an ordinary file of a certain length is system-dependent. However, normally sparse files will have values less than 1.0, and files which use indirect blocks may have a value which is greater than 1.0. In general the number of blocks used by a file is file system dependent. The value used for BLOCKSIZE is system-dependent, but is usually 512 bytes. If the file size is zero, the value printed is undefined. On systems which lack support for st_blocks, a file's sparseness is assumed to be 1.0. %t File's last modification time in the format returned by the C ctime(3) function. %Tk File's last modification time in the format specified by k, which is the same as for %A. %u File's user name, or numeric user ID if the user has no name. %U File's numeric user ID. %y File's type (like in ls -l), U=unknown type (shouldn't happen) %Y File's type (like %y), plus follow symbolic links: `L'=loop, `N'=nonexistent, `?' for any other error when determining the type of the target of a symbolic link. %Z (SELinux only) file's security context. %{ %[ %( Reserved for future use. A `%' character followed by any other character is discarded, but the other character is printed (don't rely on this, as further format characters may be introduced). A `%' at the end of the format argument causes undefined behaviour since there is no following character. In some locales, it may hide your door keys, while in others it may remove the final page from the novel you are reading. The %m and %d directives support the #, 0 and + flags, but the other directives do not, even if they print numbers. Numeric directives that do not support these flags include G, U, b, D, k and n. The `-' format flag is supported and changes the alignment of a field from right-justified (which is the default) to left-justified. See the UNUSUAL FILENAMES section for information about how unusual characters in filenames are handled. -prune True; if the file is a directory, do not descend into it. If -depth is given, then -prune has no effect. Because -delete implies -depth, you cannot usefully use -prune and -delete together. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found, do something like this: find . -path ./src/emacs -prune -o -print -quit Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, while -quit simply makes find stop immediately. No child processes will be left running. Any command lines which have been built by -exec ... + or -execdir ... + are invoked before the program is exited. After -quit is executed, no more files specified on the command line will be processed. For example, `find /tmp/foo /tmp/bar -print -quit` will print only `/tmp/foo`. One common use of -quit is to stop searching the file system once we have found what we want. For example, if we want to find just a single file we can do this: find / -name needle -print -quit OPERATORS Listed in order of decreasing precedence: ( expr ) Force precedence. Since parentheses are special to the shell, you will normally need to quote them. Many of the examples in this manual page use backslashes for this purpose: `\(...\)' instead of `(...)'. ! expr True if expr is false. This character will also usually need protection from interpretation by the shell. -not expr Same as ! expr, but not POSIX compliant. expr1 expr2 Two expressions in a row are taken to be joined with an implied -a; expr2 is not evaluated if expr1 is false. expr1 -a expr2 Same as expr1 expr2. expr1 -and expr2 Same as expr1 expr2, but not POSIX compliant. expr1 -o expr2 Or; expr2 is not evaluated if expr1 is true. expr1 -or expr2 Same as expr1 -o expr2, but not POSIX compliant. expr1 , expr2 List; both expr1 and expr2 are always evaluated. The value of expr1 is discarded; the value of the list is the value of expr2. The comma operator can be useful for searching for several different types of thing, but traversing the filesystem hierarchy only once. The -fprintf action can be used to list the various matched items into several different output files. Please note that -a when specified implicitly (for example by two tests appearing without an explicit operator between them) or explicitly has higher precedence than -o. This means that find . -name afile -o -name bfile -print will never print afile. UNUSUAL FILENAMES top Many of the actions of find result in the printing of data which is under the control of other users. This includes file names, sizes, modification times and so forth. File names are a potential problem since they can contain any character except `\0' and `/'. Unusual characters in file names can do unexpected and often undesirable things to your terminal (for example, changing the settings of your function keys on some terminals). Unusual characters are handled differently by various actions, as described below. -print0, -fprint0 Always print the exact filename, unchanged, even if the output is going to a terminal. -ls, -fls Unusual characters are always escaped. White space, backslash, and double quote characters are printed using C-style escaping (for example `\f', `\"'). Other unusual characters are printed using an octal escape. Other printable characters (for -ls and -fls these are the characters between octal 041 and 0176) are printed as-is. -printf, -fprintf If the output is not going to a terminal, it is printed as-is. Otherwise, the result depends on which directive is in use. The directives %D, %F, %g, %G, %H, %Y, and %y expand to values which are not under control of files' owners, and so are printed as-is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t, %u and %U have values which are under the control of files' owners but which cannot be used to send arbitrary data to the terminal, and so these are printed as-is. The directives %f, %h, %l, %p and %P are quoted. This quoting is performed in the same way as for GNU ls. This is not the same quoting mechanism as the one used for -ls and -fls. If you are able to decide what format to use for the output of find then it is normally better to use `\0' as a terminator than to use newline, as file names can contain white space and newline characters. The setting of the LC_CTYPE environment variable is used to determine which characters need to be quoted. -print, -fprint Quoting is handled in the same way as for -printf and -fprintf. If you are using find in a script or in a situation where the matched files might have arbitrary names, you should consider using -print0 instead of -print. The -ok and -okdir actions print the current filename as-is. This may change in a future release. STANDARDS CONFORMANCE top For closest compliance to the POSIX standard, you should set the POSIXLY_CORRECT environment variable. The following options are specified in the POSIX standard (IEEE Std 1003.1-2008, 2016 Edition): -H This option is supported. -L This option is supported. -name This option is supported, but POSIX conformance depends on the POSIX conformance of the system's fnmatch(3) library function. As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) match a leading `.', because IEEE PASC interpretation 126 requires this. This is a change from previous versions of findutils. -type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and `s'. GNU find also supports `D', representing a Door, where the OS provides these. Furthermore, GNU find allows multiple types to be specified at once in a comma- separated list. -ok Supported. Interpretation of the response is according to the `yes' and `no' patterns selected by setting the LC_MESSAGES environment variable. When the POSIXLY_CORRECT environment variable is set, these patterns are taken system's definition of a positive (yes) or negative (no) response. See the system's documentation for nl_langinfo(3), in particular YESEXPR and NOEXPR. When POSIXLY_CORRECT is not set, the patterns are instead taken from find's own message catalogue. -newer Supported. If the file specified is a symbolic link, it is always dereferenced. This is a change from previous behaviour, which used to take the relevant time from the symbolic link; see the HISTORY section below. -perm Supported. If the POSIXLY_CORRECT environment variable is not set, some mode arguments (for example +a+x) which are not valid in POSIX are supported for backward- compatibility. Other primaries The primaries -atime, -ctime, -depth, -exec, -group, -links, -mtime, -nogroup, -nouser, -ok, -path, -print, -prune, -size, -user and -xdev are all supported. The POSIX standard specifies parentheses `(', `)', negation `!' and the logical AND/OR operators -a and -o. All other options, predicates, expressions and so forth are extensions beyond the POSIX standard. Many of these extensions are not unique to GNU find, however. The POSIX standard requires that find detects loops: The find utility shall detect infinite loops; that is, entering a previously visited directory that is an ancestor of the last file encountered. When it detects an infinite loop, find shall write a diagnostic message to standard error and shall either recover its position in the hierarchy or terminate. GNU find complies with these requirements. The link count of directories which contain entries which are hard links to an ancestor will often be lower than they otherwise should be. This can mean that GNU find will sometimes optimise away the visiting of a subdirectory which is actually a link to an ancestor. Since find does not actually enter such a subdirectory, it is allowed to avoid emitting a diagnostic message. Although this behaviour may be somewhat confusing, it is unlikely that anybody actually depends on this behaviour. If the leaf optimisation has been turned off with -noleaf, the directory entry will always be examined and the diagnostic message will be issued where it is appropriate. Symbolic links cannot be used to create filesystem cycles as such, but if the -L option or the -follow option is in use, a diagnostic message is issued when find encounters a loop of symbolic links. As with loops containing hard links, the leaf optimisation will often mean that find knows that it doesn't need to call stat() or chdir() on the symbolic link, so this diagnostic is frequently not necessary. The -d option is supported for compatibility with various BSD systems, but you should use the POSIX-compliant option -depth instead. The POSIXLY_CORRECT environment variable does not affect the behaviour of the -regex or -iregex tests because those tests aren't specified in the POSIX standard. ENVIRONMENT VARIABLES top LANG Provides a default value for the internationalization variables that are unset or null. LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables. LC_COLLATE The POSIX standard specifies that this variable affects the pattern matching to be used for the -name option. GNU find uses the fnmatch(3) library function, and so support for LC_COLLATE depends on the system library. This variable also affects the interpretation of the response to -ok; while the LC_MESSAGES variable selects the actual pattern used to interpret the response to -ok, the interpretation of any bracket expressions in the pattern will be affected by LC_COLLATE. LC_CTYPE This variable affects the treatment of character classes used in regular expressions and also with the -name test, if the system's fnmatch(3) library function supports this. This variable also affects the interpretation of any character classes in the regular expressions used to interpret the response to the prompt issued by -ok. The LC_CTYPE environment variable will also affect which characters are considered to be unprintable when filenames are printed; see the section UNUSUAL FILENAMES. LC_MESSAGES Determines the locale to be used for internationalised messages. If the POSIXLY_CORRECT environment variable is set, this also determines the interpretation of the response to the prompt made by the -ok action. NLSPATH Determines the location of the internationalisation message catalogues. PATH Affects the directories which are searched to find the executables invoked by -exec, -execdir, -ok and -okdir. POSIXLY_CORRECT Determines the block size used by -ls and -fls. If POSIXLY_CORRECT is set, blocks are units of 512 bytes. Otherwise they are units of 1024 bytes. Setting this variable also turns off warning messages (that is, implies -nowarn) by default, because POSIX requires that apart from the output for -ok, all messages printed on stderr are diagnostics and must result in a non-zero exit status. When POSIXLY_CORRECT is not set, -perm +zzz is treated just like -perm /zzz if +zzz is not a valid symbolic mode. When POSIXLY_CORRECT is set, such constructs are treated as an error. When POSIXLY_CORRECT is set, the response to the prompt made by the -ok action is interpreted according to the system's message catalogue, as opposed to according to find's own message translations. TZ Affects the time zone used for some of the time-related format directives of -printf and -fprintf. EXAMPLES top Simple `find|xargs` approach Find files named core in or below the directory /tmp and delete them. $ find /tmp -name core -type f -print | xargs /bin/rm -f Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. Safer `find -print0 | xargs -0` approach Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. $ find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f The -name test comes before the -type test in order to avoid having to call stat(2) on every file. Note that there is still a race between the time find traverses the hierarchy printing the matching filenames, and the time the process executed by xargs works with that file. Processing arbitrary starting points Given that another program proggy pre-filters and creates a huge NUL-separated list of files, process those as starting points, and find all regular, empty files among them: $ proggy | find -files0-from - -maxdepth 0 -type f -empty The use of `-files0-from -` means to read the names of the starting points from standard input, i.e., from the pipe; and -maxdepth 0 ensures that only explicitly those entries are examined without recursing into directories (in the case one of the starting points is one). Executing a command for each file Run file on every file in or below the current directory. $ find . -type f -exec file '{}' \; Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. In many cases, one might prefer the `-exec ... +` or better the `-execdir ... +` syntax for performance and security reasons. Traversing the filesystem just once - for 2 different actions Traverse the filesystem just once, listing set-user-ID files and directories into /root/suid.txt and large files into /root/big.txt. $ find / \ \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) This example uses the line-continuation character '\' on the first two lines to instruct the shell to continue reading the command on the next line. Searching files by age Search for files in your home directory which have been modified in the last twenty-four hours. $ find $HOME -mtime 0 This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. Searching files by permissions Search for files which are executable but not readable. $ find /sbin /usr/sbin -executable \! -readable -print Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. $ find . -perm 664 Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). $ find . -perm -664 This will match a file which has mode 0777, for example. Search for files which are writable by somebody (their owner, or their group, or anybody else). $ find . -perm /222 Search for files which are writable by either their owner or their group. $ find . -perm /220 $ find . -perm /u+w,g+w $ find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. The files don't have to be writable by both the owner and group to be matched; either will do. Search for files which are writable by both their owner and their group. $ find . -perm -220 $ find . -perm -g+w,u+w Both these commands do the same thing. A more elaborate search on permissions. $ find . -perm -444 -perm /222 \! -perm /111 $ find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody (-perm -444 or -perm -a+r), have at least one write bit set (-perm /222 or -perm /a+w) but are not executable for anybody (! -perm /111 or ! -perm /a+x respectively). Pruning - omitting files and subdirectories Copy the contents of /source-dir to /dest-dir, but omit files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in `~', but not their contents. $ cd /source-dir $ find . -name .snapshot -prune -o \( \! -name '*~' -print0 \) \ | cpio -pmd0 /dest-dir The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: $ find repo/ \ \( -exec test -d '{}/.svn' \; \ -or -exec test -d '{}/.git' \; \ -or -exec test -d '{}/CVS' \; \ \) -print -prune Sample output: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. Other useful examples Search for several file types. $ find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: $ find /tmp \( -type f -o -type d -o -type l \) Search for files with the particular name needle and stop immediately when we find the first one. $ find / -name needle -print -quit Demonstrate the interpretation of the %f and %h format directives of the -printf action for some corner-cases. Here is an example including some output. $ find . .. / /tmp /tmp/TRACE compile compile/64/tests/find -maxdepth 0 -printf '[%h][%f]\n' [.][.] [.][..] [][/] [][tmp] [/tmp][TRACE] [.][compile] [compile/64/tests][find] EXIT STATUS top find exits with status 0 if all files are processed successfully, greater than 0 if errors occur. This is deliberately a very broad description, but if the return value is non-zero, you should not rely on the correctness of the results of find. When some error occurs, find may stop immediately, without completing all the actions specified. For example, some starting points may not have been examined or some pending program invocations for -exec ... {} + or -execdir ... {} + may not have been performed. HISTORY top A find program appeared in Version 5 Unix as part of the Programmer's Workbench project and was written by Dick Haight. Doug McIlroy's A Research UNIX Reader: Annotated Excerpts from the Programmers Manual, 1971-1986 provides some additional details; you can read it on-line at <https://www.cs.dartmouth.edu/~doug/reader.pdf>. GNU find was originally written by Eric Decker, with enhancements by David MacKenzie, Jay Plett, and Tim Wood. The idea for find -print0 and xargs -0 came from Dan Bernstein. COMPATIBILITY top As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -files0-from 4.9.0 -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005. NON-BUGS top Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. paths must precede expression error message $ find . -name *.c -print find: paths must precede expression find: possible unquoted pattern after predicate `-name'? This happens when the shell could expand the pattern *.c to more than one file name existing in the current directory, and passing the resulting file names in the command line to find like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work, because the -name predicate allows exactly only one pattern as argument. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard, thus allowing find to use the pattern with the wildcard during the search for file name matching instead of file names expanded by the parent shell: $ find . -name '*.c' -print $ find . -name \*.c -print BUGS top There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. The environment variable LC_COLLATE has no effect on the -ok action. REPORTING BUGS top GNU findutils online help: <https://www.gnu.org/software/findutils/#get-help> Report any translation bugs to <https://translationproject.org/team/> Report any other issue via the form at the GNU Savannah bug tracker: <https://savannah.gnu.org/bugs/?group=findutils> General topics about the GNU findutils package are discussed at the bug-findutils mailing list: <https://lists.gnu.org/mailman/listinfo/bug-findutils> COPYRIGHT top Copyright 1990-2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top chmod(1), locate(1), ls(1), updatedb(1), xargs(1), lstat(2), stat(2), ctime(3) fnmatch(3), printf(3), strftime(3), locatedb(5), regex(7) Full documentation <https://www.gnu.org/software/findutils/find> or available locally via: info find COLOPHON top This page is part of the findutils (find utilities) project. Information about the project can be found at http://www.gnu.org/software/findutils/. If you have a bug report for this manual page, see https://savannah.gnu.org/bugs/?group=findutils. This page was obtained from the project's upstream Git repository git://git.savannah.gnu.org/findutils.git on 2023-12-22. (At that time, the date of the most recent commit that was found in the repository was 2023-11-11.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org FIND(1) Pages that refer to this page: dpkg(1), dpkg-name(1), find-filter(1), grep(1), ippfind(1), locate(1), mkaf(1), pmlogger_daily(1), tar(1), updatedb(1), xargs(1), fts(3), proc(5), hier(7), symlink(7) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. test(1) - Linux manual page man7.org > Linux > man-pages Linux/UNIX system programming training test(1) Linux manual page NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO | COLOPHON TEST(1) User Commands TEST(1) NAME top test - check file types and compare values SYNOPSIS top test EXPRESSION test [ EXPRESSION ] [ ] [ OPTION DESCRIPTION top Exit with the status determined by EXPRESSION. --help display this help and exit --version output version information and exit An omitted EXPRESSION defaults to false. Otherwise, EXPRESSION is true or false and sets exit status. It is one of: ( EXPRESSION ) EXPRESSION is true ! EXPRESSION EXPRESSION is false EXPRESSION1 -a EXPRESSION2 both EXPRESSION1 and EXPRESSION2 are true EXPRESSION1 -o EXPRESSION2 either EXPRESSION1 or EXPRESSION2 is true -n STRING the length of STRING is nonzero STRING equivalent to -n STRING -z STRING the length of STRING is zero STRING1 = STRING2 the strings are equal STRING1 != STRING2 the strings are not equal INTEGER1 -eq INTEGER2 INTEGER1 is equal to INTEGER2 INTEGER1 -ge INTEGER2 INTEGER1 is greater than or equal to INTEGER2 INTEGER1 -gt INTEGER2 INTEGER1 is greater than INTEGER2 INTEGER1 -le INTEGER2 INTEGER1 is less than or equal to INTEGER2 INTEGER1 -lt INTEGER2 INTEGER1 is less than INTEGER2 INTEGER1 -ne INTEGER2 INTEGER1 is not equal to INTEGER2 FILE1 -ef FILE2 FILE1 and FILE2 have the same device and inode numbers FILE1 -nt FILE2 FILE1 is newer (modification date) than FILE2 FILE1 -ot FILE2 FILE1 is older than FILE2 -b FILE FILE exists and is block special -c FILE FILE exists and is character special -d FILE FILE exists and is a directory -e FILE FILE exists -f FILE FILE exists and is a regular file -g FILE FILE exists and is set-group-ID -G FILE FILE exists and is owned by the effective group ID -h FILE FILE exists and is a symbolic link (same as -L) -k FILE FILE exists and has its sticky bit set -L FILE FILE exists and is a symbolic link (same as -h) -N FILE FILE exists and has been modified since it was last read -O FILE FILE exists and is owned by the effective user ID -p FILE FILE exists and is a named pipe -r FILE FILE exists and the user has read access -s FILE FILE exists and has a size greater than zero -S FILE FILE exists and is a socket -t FD file descriptor FD is opened on a terminal -u FILE FILE exists and its set-user-ID bit is set -w FILE FILE exists and the user has write access -x FILE FILE exists and the user has execute (or search) access Except for -h and -L, all FILE-related tests dereference symbolic links. Beware that parentheses need to be escaped (e.g., by backslashes) for shells. INTEGER may also be -l STRING, which evaluates to the length of STRING. NOTE: Binary -a and -o are inherently ambiguous. Use 'test EXPR1 && test EXPR2' or 'test EXPR1 || test EXPR2' instead. NOTE: [ honors the --help and --version options, but test does not. test treats each of those as it treats any other nonempty STRING. NOTE: your shell may have its own version of test and/or [, which usually supersedes the version described here. Please refer to your shell's documentation for details about the options it supports. AUTHOR top Written by Kevin Braunsdorf and Matthew Bradburn. REPORTING BUGS top GNU coreutils online help: <https://www.gnu.org/software/coreutils/> Report any translation bugs to <https://translationproject.org/team/> COPYRIGHT top Copyright 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO top access(2) Full documentation <https://www.gnu.org/software/coreutils/test> or available locally via: info '(coreutils) test invocation' COLOPHON top This page is part of the coreutils (basic file, shell and text manipulation utilities) project. Information about the project can be found at http://www.gnu.org/software/coreutils/. If you have a bug report for this manual page, see http://www.gnu.org/software/coreutils/. This page was obtained from the tarball coreutils-9.4.tar.xz fetched from http://ftp.gnu.org/gnu/coreutils/ on 2023-12-22. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org GNU coreutils 9.4 August 2023 TEST(1) HTML rendering created 2023-12-22 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. Task: Delete all empty directories in the "test" directory tree Bash Command:<START>find test -depth -type d -empty -delete<END>