# ar

## NAME



           ar - create, modify, and extract from archives
    


## SYNOPSIS



           ar [**-X32_64**] [**-**]_p_[_mod_] [**--plugin** _name_] [**--target** _bfdname_]
           [**--output** _dirname_] [**--record-libdeps** _libdeps_] [**--thin**] [_relpos_]
           [_count_] _archive_ [_member_...]
    


## DESCRIPTION



           The GNU **ar** program creates, modifies, and extracts from archives.
           An _archive_ is a single file holding a collection of other files in
           a structure that makes it possible to retrieve the original
           individual files (called _members_ of the archive).
    
           The original files' contents, mode (permissions), timestamp,
           owner, and group are preserved in the archive, and can be restored
           on extraction.
    
           GNU **ar** can maintain archives whose members have names of any
           length; however, depending on how **ar** is configured on your system,
           a limit on member-name length may be imposed for compatibility
           with archive formats maintained with other tools.  If it exists,
           the limit is often 15 characters (typical of formats related to
           a.out) or 16 characters (typical of formats related to coff).
    
           **ar** is considered a binary utility because archives of this sort
           are most often used as _libraries_ holding commonly needed
           subroutines.  Since libraries often will depend on other
           libraries, **ar** can also record the dependencies of a library when
           the **--record-libdeps** option is specified.
    
           **ar** creates an index to the symbols defined in relocatable object
           modules in the archive when you specify the modifier **s**.  Once
           created, this index is updated in the archive whenever **ar** makes a
           change to its contents (save for the **q** update operation).  An
           archive with such an index speeds up linking to the library, and
           allows routines in the library to call each other without regard
           to their placement in the archive.
    
           You may use **nm -s** or **nm --print-armap** to list this index table.
           If an archive lacks the table, another form of **ar** called **ranlib**
           can be used to add just the table.
    
           GNU **ar** can optionally create a _thin_ archive, which contains a
           symbol index and references to the original copies of the member
           files of the archive.  This is useful for building libraries for
           use within a local build tree, where the relocatable objects are
           expected to remain available, and copying the contents of each
           object would only waste time and space.
    
           An archive can either be _thin_ or it can be normal.  It cannot be
           both at the same time.  Once an archive is created its format
           cannot be changed without first deleting it and then creating a
           new archive in its place.
    
           Thin archives are also _flattened_ , so that adding one thin archive
           to another thin archive does not nest it, as would happen with a
           normal archive.  Instead the elements of the first archive are
           added individually to the second archive.
    
           The paths to the elements of the archive are stored relative to
           the archive itself.
    
           GNU **ar** is designed to be compatible with two different facilities.
           You can control its activity using command-line options, like the
           different varieties of **ar** on Unix systems; or, if you specify the
           single command-line option **-M** , you can control it with a script
           supplied via standard input, like the MRI "librarian" program.
    


## OPTIONS



           GNU **ar** allows you to mix the operation code _p_ and modifier flags
           _mod_ in any order, within the first command-line argument.
    
           If you wish, you may begin the first command-line argument with a
           dash.
    
           The _p_ keyletter specifies what operation to execute; it may be any
           of the following, but you must specify only one of them:
    
           **d** _Delete_ modules from the archive.  Specify the names of modules
               to be deleted as _member_...; the archive is untouched if you
               specify no files to delete.
    
               If you specify the **v** modifier, **ar** lists each module as it is
               deleted.
    
           **m** Use this operation to _move_ members in an archive.
    
               The ordering of members in an archive can make a difference in
               how programs are linked using the library, if a symbol is
               defined in more than one member.
    
               If no modifiers are used with "m", any members you name in the
               _member_ arguments are moved to the _end_ of the archive; you can
               use the **a** , **b** , or **i** modifiers to move them to a specified place
               instead.
    
           **p** _Print_ the specified members of the archive, to the standard
               output file.  If the **v** modifier is specified, show the member
               name before copying its contents to standard output.
    
               If you specify no _member_ arguments, all the files in the
               archive are printed.
    
           **q** _Quick append_ ; Historically, add the files _member_... to the end
               of _archive_ , without checking for replacement.
    
               The modifiers **a** , **b** , and **i** do _not_ affect this operation; new
               members are always placed at the end of the archive.
    
               The modifier **v** makes **ar** list each file as it is appended.
    
               Since the point of this operation is speed, implementations of
               **ar** have the option of not updating the archive's symbol table
               if one exists.  Too many different systems however assume that
               symbol tables are always up-to-date, so GNU **ar** will rebuild
               the table even with a quick append.
    
               Note - GNU **ar** treats the command **qs** as a synonym for **r** -
               replacing already existing files in the archive and appending
               new ones at the end.
    
           **r** Insert the files _member_... into _archive_ (with _replacement_).
               This operation differs from **q** in that any previously existing
               members are deleted if their names match those being added.
    
               If one of the files named in _member_... does not exist, **ar**
               displays an error message, and leaves undisturbed any existing
               members of the archive matching that name.
    
               By default, new members are added at the end of the file; but
               you may use one of the modifiers **a** , **b** , or **i** to request
               placement relative to some existing member.
    
               The modifier **v** used with this operation elicits a line of
               output for each file inserted, along with one of the letters **a**
               or **r** to indicate whether the file was appended (no old member
               deleted) or replaced.
    
           **s** Add an index to the archive, or update it if it already
               exists.  Note this command is an exception to the rule that
               there can only be one command letter, as it is possible to use
               it as either a command or a modifier.  In either case it does
               the same thing.
    
           **t** Display a _table_ listing the contents of _archive_ , or those of
               the files listed in _member_... that are present in the archive.
               Normally only the member name is shown, but if the modifier **O**
               is specified, then the corresponding offset of the member is
               also displayed.  Finally, in order to see the modes
               (permissions), timestamp, owner, group, and size the **v**
               modifier should be included.
    
               If you do not specify a _member_ , all files in the archive are
               listed.
    
               If there is more than one file with the same name (say, **fie**)
               in an archive (say **b.a**), **ar t b.a fie** lists only the first
               instance; to see them all, you must ask for a complete
               listing---in our example, **ar t b.a**.
    
           **x** _Extract_ members (named _member_) from the archive.  You can use
               the **v** modifier with this operation, to request that **ar** list
               each name as it extracts it.
    
               If you do not specify a _member_ , all files in the archive are
               extracted.
    
               Files cannot be extracted from a thin archive, and there are
               restrictions on extracting from archives created with **P** : The
               paths must not be absolute, may not contain "..", and any
               subdirectories in the paths must exist.  If it is desired to
               avoid these restrictions then used the **--output** option to
               specify an output directory.
    
           A number of modifiers (_mod_) may immediately follow the _p_
           keyletter, to specify variations on an operation's behavior:
    
           **a** Add new files _after_ an existing member of the archive.  If you
               use the modifier **a** , the name of an existing archive member
               must be present as the _relpos_ argument, before the _archive_
               specification.
    
           **b** Add new files _before_ an existing member of the archive.  If
               you use the modifier **b** , the name of an existing archive member
               must be present as the _relpos_ argument, before the _archive_
               specification.  (same as **i**).
    
           **c** _Create_ the archive.  The specified _archive_ is always created
               if it did not exist, when you request an update.  But a
               warning is issued unless you specify in advance that you
               expect to create it, by using this modifier.
    
           **D** Operate in _deterministic_ mode.  When adding files and the
               archive index use zero for UIDs, GIDs, timestamps, and use
               consistent file modes for all files.  When this option is
               used, if **ar** is used with identical options and identical input
               files, multiple runs will create identical output files
               regardless of the input files' owners, groups, file modes, or
               modification times.
    
               If _binutils_ was configured with
               **--enable-deterministic-archives** , then this mode is on by
               default.  It can be disabled with the **U** modifier, below.
    
           **f** Truncate names in the archive.  GNU **ar** will normally permit
               file names of any length.  This will cause it to create
               archives which are not compatible with the native **ar** program
               on some systems.  If this is a concern, the **f** modifier may be
               used to truncate file names when putting them in the archive.
    
           **i** Insert new files _before_ an existing member of the archive.  If
               you use the modifier **i** , the name of an existing archive member
               must be present as the _relpos_ argument, before the _archive_
               specification.  (same as **b**).
    
           **l** Specify dependencies of this library.  The dependencies must
               immediately follow this option character, must use the same
               syntax as the linker command line, and must be specified
               within a single argument.  I.e., if multiple items are needed,
               they must be quoted to form a single command line argument.
               For example **l "-L/usr/local/lib -lmydep1 -lmydep2"**
    
           **N** Uses the _count_ parameter.  This is used if there are multiple
               entries in the archive with the same name.  Extract or delete
               instance _count_ of the given name from the archive.
    
           **o** Preserve the _original_ dates of members when extracting them.
               If you do not specify this modifier, files extracted from the
               archive are stamped with the time of extraction.
    
           **O** Display member offsets inside the archive. Use together with
               the **t** option.
    
           **P** Use the full path name when matching or storing names in the
               archive.  Archives created with full path names are not POSIX
               compliant, and thus may not work with tools other than up to
               date GNU tools.  Modifying such archives with GNU **ar** without
               using **P** will remove the full path names unless the archive is
               a thin archive.  Note that **P** may be useful when adding files
               to a thin archive since **r** without **P** ignores the path when
               choosing which element to replace.  Thus
    
                       ar rcST archive.a subdir/file1 subdir/file2 file1
    
               will result in the first "subdir/file1" being replaced with
               "file1" from the current directory.  Adding **P** will prevent
               this replacement.
    
           **s** Write an object-file index into the archive, or update an
               existing one, even if no other change is made to the archive.
               You may use this modifier flag either with any operation, or
               alone.  Running **ar s** on an archive is equivalent to running
               **ranlib** on it.
    
           **S** Do not generate an archive symbol table.  This can speed up
               building a large library in several steps.  The resulting
               archive can not be used with the linker.  In order to build a
               symbol table, you must omit the **S** modifier on the last
               execution of **ar** , or you must run **ranlib** on the archive.
    
           **T** Deprecated alias for **--thin**.  **T** is not recommended because in
               many ar implementations **T** has a different meaning, as
               specified by X/Open System Interface.
    
           **u** Normally, **ar r**... inserts all files listed into the archive.
               If you would like to insert _only_ those of the files you list
               that are newer than existing members of the same names, use
               this modifier.  The **u** modifier is allowed only for the
               operation **r**(replace).  In particular, the combination **qu** is
               not allowed, since checking the timestamps would lose any
               speed advantage from the operation **q**.
    
               Note - if an archive has been created in a deterministic
               manner, eg via the use of the **D** modifier, then replacement
               will always happen and the **u** modifier will be ineffective.
    
           **U** Do _not_ operate in _deterministic_ mode.  This is the inverse of
               the **D** modifier, above: added files and the archive index will
               get their actual UID, GID, timestamp, and file mode values.
    
               This is the default unless _binutils_ was configured with
               **--enable-deterministic-archives**.
    
           **v** This modifier requests the _verbose_ version of an operation.
               Many operations display additional information, such as
               filenames processed, when the modifier **v** is appended.
    
           **V** This modifier shows the version number of **ar**.
    
           The **ar** program also supports some command-line options which are
           neither modifiers nor actions, but which do change its behaviour
           in specific ways:
    
           **--help**
               Displays the list of command-line options supported by **ar** and
               then exits.
    
           **--version**
               Displays the version information of **ar** and then exits.
    
           **-X32_64**
               **ar** ignores an initial option spelled **-X32_64** , for
               compatibility with AIX.  The behaviour produced by this option
               is the default for GNU **ar**.  **ar** does not support any of the
               other **-X** options; in particular, it does not support **-X32**
               which is the default for AIX **ar**.
    
           **--plugin** _name_
               The optional command-line switch **--plugin** _name_ causes **ar** to
               load the plugin called _name_ which adds support for more file
               formats, including object files with link-time optimization
               information.
    
               This option is only available if the toolchain has been built
               with plugin support enabled.
    
               If **--plugin** is not provided, but plugin support has been
               enabled then **ar** iterates over the files in
               _${libdir}/bfd-plugins_ in alphabetic order and the first plugin
               that claims the object in question is used.
    
               Please note that this plugin search directory is _not_ the one
               used by **ld** 's **-plugin** option.  In order to make **ar** use the
               linker plugin it must be copied into the _${libdir}/bfd-plugins_
               directory.  For GCC based compilations the linker plugin is
               called _liblto_plugin.so.0.0.0_.  For Clang based compilations
               it is called _LLVMgold.so_.  The GCC plugin is always backwards
               compatible with earlier versions, so it is sufficient to just
               copy the newest one.
    
           **--target** _target_
               The optional command-line switch **--target** _bfdname_ specifies
               that the archive members are in an object code format
               different from your system's default format.  See
    
           **--output** _dirname_
               The **--output** option can be used to specify a path to a
               directory into which archive members should be extracted.  If
               this option is not specified then the current directory will
               be used.
    
               Note - although the presence of this option does imply a **x**
               extraction operation that option must still be included on the
               command line.
    
           **--record-libdeps** _libdeps_
               The **--record-libdeps** option is identical to the **l** modifier,
               just handled in long form.
    
           **--thin**
               Make the specified _archive_ a _thin_ archive.  If it already
               exists and is a regular archive, the existing members must be
               present in the same directory as _archive_.
    
           **@**_file_
               Read command-line options from _file_.  The options read are
               inserted in place of the original @_file_ option.  If _file_ does
               not exist, or cannot be read, then the option will be treated
               literally, and not removed.
    
               Options in _file_ are separated by whitespace.  A whitespace
               character may be included in an option by surrounding the
               entire option in either single or double quotes.  Any
               character (including a backslash) may be included by prefixing
               the character to be included with a backslash.  The _file_ may
               itself contain additional @_file_ options; any such options will
               be processed recursively.
    


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