curlコマンドでのHTTP（HTTPS）通信のメモ

curlコマンドでのHTTP（HTTPS）通信のメモです。

# 環境

+ OS：CentOS Linux release 7.8.2003

# コマンドメモ

### 1. GET

`curl -H "[ヘッダーキー1]: [ヘッダー値1]" -H "[ヘッダーキー2]: [ヘッダー値2]" https://yasushi.co.jp/api/sample`

```bash:例
curl -H "Content-Type: application/json" -H "authkey: xxxxxxxxxx" https://yasushi.co.jp/api/sample
```

### 2. GET（クエリ文字列）

`curl -H "[ヘッダーキー1]: [ヘッダー値1]" -H "[ヘッダーキー2]: [ヘッダー値2]" https://yasushi.co.jp/api/sample?[key1]=[value1]&[key2]=[value2]`

```bash:例
curl -H "Content-Type: application/json" -H "authkey: xxxxxxxxxx" https://yasushi.co.jp/api/sample?id=0001&name=yasushi
```

### 3. POST（JSON）

`curl X POST -H "[ヘッダーキー1]: [ヘッダー値1]" -H "[ヘッダーキー2]: [ヘッダー値2]"  -d "{JSON文字列}" https://yasushi.co.jp/api/sample`

```bash:例
curl X POST -H "Content-Type: application/json" -H "authkey: xxxxxxxxxx"  -d "{\"[id]\" : \"0001\", {\"name" : \"yasushi\"}" https://yasushi.co.jp/api/sample
```

### 4. POST（application/x-www-form-urlencoded 形式）

`curl X POST -H "[ヘッダーキー1]: [ヘッダー値1]" -d [key1]=[value1] -d [key2]=[value2] https://yasushi.co.jp/api/sample`

```bash:例
curl X POST -H "authkey: xxxxxxxxxx"  -d id=0001 -d name=yasushi https://yasushi.co.jp/api/sample
```

### 5. POST（multipart/form-data 形式）

`curl X POST -H "[ヘッダーキー1]: [ヘッダー値1]" -F [key1]=[value1] -F [key2]=[value2] https://yasushi.co.jp/api/sample`

```bash:例
curl X POST -H "authkey: xxxxxxxxxx"  -F id=0001 -F name=yasushi https://yasushi.co.jp/api/sample
```

### 6. 証明書を無視

`curl -k https://yasushi.co.jp/api/sample`

```bash:例
curl -k https://yasushi.co.jp/api/sample
```

### 7. 証明書指定

`curl --cacert [証明書ファイルのパス] https://yasushi.co.jp/api/sample`

```bash:例
curl --cacert ./rootca.crt https://yasushi.co.jp/api/sample
```

### 8. プロキシ（Proxy）経由

`curl --proxy [protocol://][user:password@]proxyhost[:port] https://yasushi.co.jp/api/sample`

```bash:例
curl --proxy http://yasushi:password@proxy.co.jp:8080 https://yasushi.co.jp/api/sample
```

# 参考

<details><summary>man curl</summary><div>

```
curl(1)                           Curl Manual                          curl(1)



NAME
       curl - transfer a URL

SYNOPSIS
       curl [options] [URL...]

DESCRIPTION
       curl  is  a tool to transfer data from or to a server, using one of the
       supported protocols (DICT, FILE, FTP, FTPS, GOPHER, HTTP, HTTPS,  IMAP,
       IMAPS,  LDAP,  LDAPS,  POP3, POP3S, RTMP, RTSP, SCP, SFTP, SMTP, SMTPS,
       TELNET and TFTP).  The command is designed to work without user  inter‐
       action.

       curl offers a busload of useful tricks like proxy support, user authen‐
       tication, FTP upload, HTTP post, SSL connections, cookies, file  trans‐
       fer  resume,  Metalink,  and more. As you will see below, the number of
       features will make your head spin!

       curl is powered by  libcurl  for  all  transfer-related  features.  See
       libcurl(3) for details.

URL
       The  URL  syntax is protocol-dependent. You'll find a detailed descrip‐
       tion in RFC 3986.

       You can specify multiple URLs or parts of URLs  by  writing  part  sets
       within braces as in:

        http://site.{one,two,three}.com

       or you can get sequences of alphanumeric series by using [] as in:

        ftp://ftp.numericals.com/file[1-100].txt
        ftp://ftp.numericals.com/file[001-100].txt    (with leading zeros)
        ftp://ftp.letters.com/file[a-z].txt

       Nested  sequences  are not supported, but you can use several ones next
       to each other:

        http://any.org/archive[1996-1999]/vol[1-4]/part{a,b,c}.html

       You can specify any amount of URLs on the command line.  They  will  be
       fetched in a sequential manner in the specified order.

       You  can  specify a step counter for the ranges to get every Nth number
       or letter:

        http://www.numericals.com/file[1-100:10].txt
        http://www.letters.com/file[a-z:2].txt

       If you specify URL without protocol:// prefix,  curl  will  attempt  to
       guess  what  protocol  you might want. It will then default to HTTP but
       try other protocols based on often-used host name prefixes.  For  exam‐
       ple,  for  host names starting with "ftp." curl will assume you want to
       speak FTP.

       curl will do its best to use what you pass to it as a URL.  It  is  not
       trying  to  validate it as a syntactically correct URL by any means but
       is instead very liberal with what it accepts.

       curl will attempt to re-use connections for multiple file transfers, so
       that  getting many files from the same server will not do multiple con‐
       nects / handshakes. This improves speed. Of course this is only done on
       files  specified  on  a  single command line and cannot be used between
       separate curl invokes.

PROGRESS METER
       curl normally displays a progress meter during  operations,  indicating
       the  amount  of  transferred  data,  transfer speeds and estimated time
       left, etc.

       curl displays this data to the terminal by default, so  if  you  invoke
       curl  to do an operation and it is about to write data to the terminal,
       it disables the progress meter as otherwise it would mess up the output
       mixing progress meter and response data.

       If you want a progress meter for HTTP POST or PUT requests, you need to
       redirect the response output to a file, using shell  redirect  (>),  -o
       [file] or similar.

       It  is not the same case for FTP upload as that operation does not spit
       out any response data to the terminal.

       If you prefer a progress "bar" instead of the regular meter, -# is your
       friend.

OPTIONS
       In general, all boolean options are enabled with --option and yet again
       disabled with --no-option. That is, you use the exact same option  name
       but prefix it with "no-". However, in this list we mostly only list and
       show the --option version of them. (This concept with --no options  was
       added  in  7.19.0.  Previously  most  options  were  toggled  on/off on
       repeated use of the same command line option.)

       -#, --progress-bar
              Make curl display progress as a simple progress bar  instead  of
              the standard, more informational, meter.

       -0, --http1.0
              (HTTP)  Forces curl to issue its requests using HTTP 1.0 instead
              of using its internally preferred: HTTP 1.1.

       -1, --tlsv1
              (SSL) Forces curl to use TLS version 1.x when negotiating with a
              remote  TLS  server.   You can use options --tlsv1.0, --tlsv1.1,
              --tlsv1.2, and --tlsv1.3 to control the TLS  version  more  pre‐
              cisely  (if the SSL backend in use supports such a level of con‐
              trol).

       -2, --sslv2
              (SSL) Forces curl to use SSL version 2 when negotiating  with  a
              remote SSL server.

       -3, --sslv3
              (SSL)  Forces  curl to use SSL version 3 when negotiating with a
              remote SSL server.

       -4, --ipv4
              If curl is capable of resolving an address to multiple  IP  ver‐
              sions  (which  it  is  if it is IPv6-capable), this option tells
              curl to resolve names to IPv4 addresses only.

       -6, --ipv6
              If curl is capable of resolving an address to multiple  IP  ver‐
              sions  (which  it  is  if it is IPv6-capable), this option tells
              curl to resolve names to IPv6 addresses only.

       -a, --append
              (FTP/SFTP) When used in an upload, this will tell curl to append
              to  the  target  file  instead  of  overwriting  it. If the file
              doesn't exist, it will be  created.   Note  that  this  flag  is
              ignored by some SSH servers (including OpenSSH).

       -A, --user-agent <agent string>
              (HTTP) Specify the User-Agent string to send to the HTTP server.
              Some  badly  done  CGIs  fail  if  this  field  isn't   set   to
              "Mozilla/4.0".  To  encode  blanks  in  the string, surround the
              string with single quote marks. This can also be  set  with  the
              -H, --header option of course.

              If this option is used several times, the last one will be used.

       --anyauth
              (HTTP) Tells curl to figure out authentication method by itself,
              and use the most secure one the remote site claims  to  support.
              This is done by first doing a request and checking the response-
              headers, thus possibly inducing  an  extra  network  round-trip.
              This  is  used  instead  of  setting  a  specific authentication
              method, which you can do with  --basic,  --digest,  --ntlm,  and
              --negotiate.

              Note  that  using --anyauth is not recommended if you do uploads
              from stdin, since it may require data to be sent twice and  then
              the client must be able to rewind. If the need should arise when
              uploading from stdin, the upload operation will fail.

       -b, --cookie <name=data>
              (HTTP) Pass the data to the HTTP server as a cookie. It is  sup‐
              posedly  the data previously received from the server in a "Set-
              Cookie:" line.  The data should be in the format  "NAME1=VALUE1;
              NAME2=VALUE2".

              If  no  '=' symbol is used in the line, it is treated as a file‐
              name to use to read previously stored cookie lines  from,  which
              should  be used in this session if they match. Using this method
              also activates the "cookie parser" which will make  curl  record
              incoming cookies too, which may be handy if you're using this in
              combination with the -L, --location option. The file  format  of
              the  file  to  read cookies from should be plain HTTP headers or
              the Netscape/Mozilla cookie file format.

              NOTE that the file specified with -b, --cookie is only  used  as
              input.  No cookies will be stored in the file. To store cookies,
              use the -c, --cookie-jar option or you could even save the  HTTP
              headers to a file using -D, --dump-header!

              If this option is used several times, the last one will be used.

       -B, --use-ascii
              (FTP/LDAP)  Enable  ASCII  transfer.  For  FTP, this can also be
              enforced by using an URL that ends with ";type=A".  This  option
              causes data sent to stdout to be in text mode for win32 systems.

       --basic
              (HTTP)  Tells curl to use HTTP Basic authentication. This is the
              default and this option is usually pointless, unless you use  it
              to  override  a  previously  set  option  that  sets a different
              authentication method (such as --ntlm,  --digest,  or  --negoti‐
              ate).

       -c, --cookie-jar <file name>
              (HTTP)  Specify to which file you want curl to write all cookies
              after a completed operation. Curl writes all cookies  previously
              read  from a specified file as well as all cookies received from
              remote server(s). If no cookies are known, no file will be writ‐
              ten.  The  file  will  be written using the Netscape cookie file
              format. If you set the file name to  a  single  dash,  "-",  the
              cookies will be written to stdout.

              This  command  line  option will activate the cookie engine that
              makes curl record and use cookies. Another way to activate it is
              to use the -b, --cookie option.

              If the cookie jar can't be created or written to, the whole curl
              operation won't fail or even report an error clearly.  Using  -v
              will get a warning displayed, but that is the only visible feed‐
              back you get about this possibly lethal situation.

              If this option is used several times, the  last  specified  file
              name will be used.

       -C, --continue-at <offset>
              Continue/Resume  a  previous  file transfer at the given offset.
              The given offset is the exact  number  of  bytes  that  will  be
              skipped,  counting  from the beginning of the source file before
              it is transferred to the destination.  If used with uploads, the
              FTP server command SIZE will not be used by curl.

              Use  "-C  -" to tell curl to automatically find out where/how to
              resume the transfer. It then uses the given  output/input  files
              to figure that out.

              If this option is used several times, the last one will be used.

       --ciphers <list of ciphers>
              (SSL) Specifies which ciphers to use in the connection. The list
              of ciphers must specify valid ciphers. Read  up  on  SSL  cipher
              list           details           on           this          URL:
              http://www.openssl.org/docs/apps/ciphers.html

              NSS ciphers are done differently than OpenSSL  and  GnuTLS.  The
              full  list of NSS ciphers is in the NSSCipherSuite entry at this
              URL:                                          http://git.fedora‐
              hosted.org/cgit/mod_nss.git/plain/docs/mod_nss.html#Directives

              If this option is used several times, the last one will be used.

       --compressed
              (HTTP) Request a compressed response using one of the algorithms
              curl supports, and save  the  uncompressed  document.   If  this
              option  is  used  and  the server sends an unsupported encoding,
              curl will report an error.

       --connect-timeout <seconds>
              Maximum time in seconds that you allow  the  connection  to  the
              server  to  take.   This  only limits the connection phase, once
              curl has connected this option is of no more use. See  also  the
              -m, --max-time option.

              If this option is used several times, the last one will be used.

       --create-dirs
              When  used  in  conjunction with the -o option, curl will create
              the necessary local directory hierarchy as needed.  This  option
              creates  the dirs mentioned with the -o option, nothing else. If
              the -o file name uses no dir or if the dirs it mentions  already
              exist, no dir will be created.

              To  create remote directories when using FTP or SFTP, try --ftp-
              create-dirs.

       --crlf (FTP) Convert LF to CRLF in upload. Useful for MVS (OS/390).

       --crlfile <file>
              (HTTPS/FTPS) Provide a file using PEM format with a  Certificate
              Revocation  List  that may specify peer certificates that are to
              be considered revoked.

              If this option is used several times, the last one will be used.

              (Added in 7.19.7)

       -d, --data <data>
              (HTTP) Sends the specified data in a POST request  to  the  HTTP
              server,  in  the  same  way  that a browser does when a user has
              filled in an HTML form and presses the submit button. This  will
              cause curl to pass the data to the server using the content-type
              application/x-www-form-urlencoded.  Compare to -F, --form.

              -d, --data is the same as  --data-ascii.  To  post  data  purely
              binary, you should instead use the --data-binary option. To URL-
              encode the value of a form field you may use --data-urlencode.

              If any of these options is used more than once on the same  com‐
              mand  line,  the  data  pieces specified will be merged together
              with a separating  &-symbol.  Thus,  using  '-d  name=daniel  -d
              skill=lousy'  would  generate  a  post  chunk  that  looks  like
              'name=daniel&skill=lousy'.

              If you start the data with the letter @, the rest  should  be  a
              file  name  to read the data from, or - if you want curl to read
              the data from stdin.  The contents of the file must  already  be
              URL-encoded.  Multiple files can also be specified. Posting data
              from a file named 'foobar' would thus be done with --data  @foo‐
              bar.

       -D, --dump-header <file>
              Write the protocol headers to the specified file.

              This  option  is handy to use when you want to store the headers
              that an HTTP site sends to you. Cookies from the  headers  could
              then  be  read  in  a  second  curl  invocation by using the -b,
              --cookie option! The -c, --cookie-jar option is however a better
              way to store cookies.

              When  used  in FTP, the FTP server response lines are considered
              being "headers" and thus are saved there.

              If this option is used several times, the last one will be used.


       --data-ascii <data>
              See -d, --data.

       --data-binary <data>
              (HTTP) This posts data exactly as specified with no  extra  pro‐
              cessing whatsoever.

              If  you  start  the data with the letter @, the rest should be a
              filename.  Data is posted in a similar  manner  as  --data-ascii
              does,  except  that  newlines  are preserved and conversions are
              never done.

              If this option is used several times,  the  ones  following  the
              first will append data as described in -d, --data.

       --data-urlencode <data>
              (HTTP) This posts data, similar to the other --data options with
              the exception that this performs URL-encoding. (Added in 7.18.0)

              To be CGI-compliant, the <data> part should begin  with  a  name
              followed  by a separator and a content specification. The <data>
              part can be passed to curl using one of the following syntaxes:

              content
                     This will make curl URL-encode the content and pass  that
                     on.  Just  be careful so that the content doesn't contain
                     any = or @ symbols, as that will  then  make  the  syntax
                     match one of the other cases below!

              =content
                     This  will make curl URL-encode the content and pass that
                     on. The preceding = symbol is not included in the data.

              name=content
                     This will make curl URL-encode the content part and  pass
                     that  on.  Note that the name part is expected to be URL-
                     encoded already.

              @filename
                     This will  make  curl  load  data  from  the  given  file
                     (including  any  newlines), URL-encode that data and pass
                     it on in the POST.

              name@filename
                     This will  make  curl  load  data  from  the  given  file
                     (including  any  newlines), URL-encode that data and pass
                     it on in the POST. The  name  part  gets  an  equal  sign
                     appended, resulting in name=urlencoded-file-content. Note
                     that the name is expected to be URL-encoded already.

       --delegation LEVEL
              Set LEVEL to tell the server what it is allowed to delegate when
              it comes to user credentials. Used with GSS/kerberos.

              none   Don't allow any delegation.

              policy Delegates  if  and only if the OK-AS-DELEGATE flag is set
                     in the Kerberos service ticket,  which  is  a  matter  of
                     realm policy.

              always Unconditionally allow the server to delegate.

       --digest
              (HTTP)  Enables HTTP Digest authentication. This is an authenti‐
              cation scheme that prevents the password from  being  sent  over
              the  wire in clear text. Use this in combination with the normal
              -u, --user option to  set  user  name  and  password.  See  also
              --ntlm, --negotiate and --anyauth for related options.

              If  this  option  is  used  several times, only the first one is
              used.

       --disable-eprt
              (FTP) Tell curl to disable the use of the EPRT and LPRT commands
              when doing active FTP transfers. Curl will normally always first
              attempt to use EPRT, then LPRT before using PORT, but with  this
              option,  it  will  use PORT right away. EPRT and LPRT are exten‐
              sions to the original FTP protocol, and  may  not  work  on  all
              servers, but they enable more functionality in a better way than
              the traditional PORT command.

              --eprt can be used to explicitly enable EPRT again and --no-eprt
              is an alias for --disable-eprt.

              If  the  server is an IPv6 host, this option will have no effect
              as EPRT is necessary then.

              Disabling EPRT only changes the active behavior. If you want  to
              switch  to  passive  mode  you need to not use -P, --ftp-port or
              force it with --ftp-pasv.

       --disable-epsv
              (FTP) Tell curl to disable the use  of  the  EPSV  command  when
              doing  passive  FTP  transfers.  Curl will normally always first
              attempt to use EPSV before PASV, but with this option,  it  will
              not try using EPSV.

              --epsv can be used to explicitly enable EPSV again and --no-epsv
              is an alias for --disable-epsv.

              If the server is an IPv6 host, this option will have  no  effect
              as EPSV is necessary then.

              Disabling EPSV only changes the passive behavior. If you want to
              switch to active mode you need to use -P, --ftp-port.

       -e, --referer <URL>
              (HTTP) Sends the "Referer Page" information to the HTTP  server.
              This can also be set with the -H, --header flag of course.  When
              used with -L, --location you can append ";auto" to the --referer
              URL to make curl automatically set the previous URL when it fol‐
              lows a Location: header. The ";auto" string can be  used  alone,
              even if you don't set an initial --referer.

              If this option is used several times, the last one will be used.

       -E, --cert <certificate[:password]>
              (SSL)  Tells  curl  to use the specified client certificate file
              when getting a file with HTTPS, FTPS or another SSL-based proto‐
              col.  The  certificate  must  be in PEM format.  If the optional
              password isn't specified, it will be queried for on  the  termi‐
              nal.  Note that this option assumes a "certificate" file that is
              the private key and the private  certificate  concatenated!  See
              --cert and --key to specify them independently.

              If  curl  is  built against the NSS SSL library then this option
              can tell curl the nickname of the certificate to use within  the
              NSS  database defined by the environment variable SSL_DIR (or by
              default /etc/pki/nssdb). If the NSS  PEM  PKCS#11  module  (lib‐
              nsspem.so)  is  available  then  PEM files may be loaded. If you
              want to use a file from the current directory, please precede it
              with  "./"  prefix, in order to avoid confusion with a nickname.
              If the nickname contains ":", it needs to be preceded by "\"  so
              that  it  is not recognized as password delimiter.  If the nick‐
              name contains "\", it needs to be escaped as "\\" so that it  is
              not recognized as an escape character.

              If this option is used several times, the last one will be used.

       --engine <name>
              Select  the  OpenSSL crypto engine to use for cipher operations.
              Use --engine list  to  print  a  list  of  build-time  supported
              engines.  Note  that  not  all  (or  none) of the engines may be
              available at run-time.

       --environment
              (RISC OS ONLY) Sets a range of environment variables, using  the
              names the -w option supports, to allow easier extraction of use‐
              ful information after having run curl.

       --egd-file <file>
              (SSL) Specify the path name  to  the  Entropy  Gathering  Daemon
              socket.  The  socket  is  used to seed the random engine for SSL
              connections. See also the --random-file option.

       --cert-type <type>
              (SSL) Tells curl what certificate type the provided  certificate
              is in. PEM, DER and ENG are recognized types.  If not specified,
              PEM is assumed.

              If this option is used several times, the last one will be used.

       --cacert <CA certificate>
              (SSL) Tells curl to use the specified certificate file to verify
              the  peer.  The  file  may contain multiple CA certificates. The
              certificate(s) must be in PEM format. Normally curl is built  to
              use a default file for this, so this option is typically used to
              alter that default file.

              curl recognizes the environment variable named  'CURL_CA_BUNDLE'
              if  it  is  set,  and uses the given path as a path to a CA cert
              bundle. This option overrides that variable.

              The windows version of curl will automatically  look  for  a  CA
              certs file named ´curl-ca-bundle.crt´, either in the same direc‐
              tory as curl.exe, or in the Current Working Directory, or in any
              folder along your PATH.

              If  curl  is  built  against  the  NSS  SSL library, the NSS PEM
              PKCS#11 module (libnsspem.so) needs to  be  available  for  this
              option to work properly.

              If this option is used several times, the last one will be used.

       --capath <CA certificate directory>
              (SSL)  Tells  curl to use the specified certificate directory to
              verify the peer. Multiple paths can be  provided  by  separating
              them with ":" (e.g.  "path1:path2:path3"). The certificates must
              be in PEM format, and if curl  is  built  against  OpenSSL,  the
              directory  must  have  been processed using the c_rehash utility
              supplied with OpenSSL. Using --capath can allow  OpenSSL-powered
              curl  to  make  SSL-connections much more efficiently than using
              --cacert if the --cacert file contains many CA certificates.

              If this option is set, the default capath value will be ignored,
              and if it is used several times, the last one will be used.

       -f, --fail
              (HTTP)  Fail  silently (no output at all) on server errors. This
              is mostly done to better enable scripts etc to better deal  with
              failed  attempts.  In  normal cases when an HTTP server fails to
              deliver a document, it  returns  an  HTML  document  stating  so
              (which  often  also describes why and more). This flag will pre‐
              vent curl from outputting that and return error 22.

              This method is not fail-safe and there are occasions where  non-
              successful  response  codes  will  slip through, especially when
              authentication is involved (response codes 401 and 407).

       -F, --form <name=content>
              (HTTP) This lets curl emulate a filled-in form in which  a  user
              has  pressed  the  submit  button. This causes curl to POST data
              using the  Content-Type  multipart/form-data  according  to  RFC
              2388.  This  enables uploading of binary files etc. To force the
              'content' part to be a file, prefix the  file  name  with  an  @
              sign.  To just get the content part from a file, prefix the file
              name with the symbol <. The difference between @ and <  is  then
              that  @  makes a file get attached in the post as a file upload,
              while the < makes a text field and just  get  the  contents  for
              that text field from a file.

              Example,  to send your password file to the server, where 'pass‐
              word' is the name of the form-field to which /etc/passwd will be
              the input:

              curl -F password=@/etc/passwd www.mypasswords.com

              To read content from stdin instead of a file, use - as the file‐
              name. This goes for both @ and < constructs.

              You can also  tell  curl  what  Content-Type  to  use  by  using
              'type=', in a manner similar to:

              curl -F "web=@index.html;type=text/html" url.com

              or

              curl -F "name=daniel;type=text/foo" url.com

              You  can  also explicitly change the name field of a file upload
              part by setting filename=, like this:

              curl -F "file=@localfile;filename=nameinpost" url.com

              If filename/path contains ',' or ';', it must be quoted by  dou‐
              ble-quotes like:

              curl -F "file=@\"localfile\";filename=\"nameinpost\"" url.com

              or

              curl -F 'file=@"localfile";filename="nameinpost"' url.com

              Note  that  if  a  filename/path is quoted by double-quotes, any
              double-quote or backslash within the filename must be escaped by
              backslash.

              See further examples and details in the MANUAL.

              This option can be used multiple times.

       --ftp-account [data]
              (FTP) When an FTP server asks for "account data" after user name
              and password has been provided, this data is sent off using  the
              ACCT command. (Added in 7.13.0)

              If this option is used several times, the last one will be used.

       --ftp-alternative-to-user <command>
              (FTP)  If  authenticating with the USER and PASS commands fails,
              send this  command.   When  connecting  to  Tumbleweed's  Secure
              Transport  server  over  FTPS  using a client certificate, using
              "SITE AUTH" will tell the server to retrieve the  username  from
              the certificate. (Added in 7.15.5)

       --ftp-create-dirs
              (FTP/SFTP)  When  an  FTP or SFTP URL/operation uses a path that
              doesn't currently exist on the server, the standard behavior  of
              curl is to fail. Using this option, curl will instead attempt to
              create missing directories.

       --ftp-method [method]
              (FTP) Control what method curl should use to reach a file on  an
              FTP(S)  server. The method argument should be one of the follow‐
              ing alternatives:

              multicwd
                     curl does a single CWD operation for each  path  part  in
                     the  given URL. For deep hierarchies this means very many
                     commands. This is how RFC 1738 says it  should  be  done.
                     This is the default but the slowest behavior.

              nocwd  curl  does  no  CWD at all. curl will do SIZE, RETR, STOR
                     etc and give a full path to the server for all these com‐
                     mands. This is the fastest behavior.

              singlecwd
                     curl does one CWD with the full target directory and then
                     operates on the file "normally"  (like  in  the  multicwd
                     case).  This  is  somewhat  more standards compliant than
                     'nocwd' but without the full penalty of 'multicwd'.
       (Added in 7.15.1)

       --ftp-pasv
              (FTP) Use passive mode for the data connection. Passive  is  the
              internal  default behavior, but using this option can be used to
              override a previous -P/-ftp-port option. (Added in 7.11.0)

              If this option is used several times,  only  the  first  one  is
              used.  Undoing  an  enforced passive really isn't doable but you
              must then instead enforce the correct -P, --ftp-port again.

              Passive mode means that curl will try the EPSV command first and
              then PASV, unless --disable-epsv is used.

       --ftp-skip-pasv-ip
              (FTP) Tell curl to not use the IP address the server suggests in
              its response to curl's PASV command when curl connects the  data
              connection.  Instead  curl  will  re-use  the same IP address it
              already uses for the control connection. (Added in 7.14.2)

              This option has no effect if PORT, EPRT or EPSV is used  instead
              of PASV.

       --ftp-pret
              (FTP)  Tell  curl to send a PRET command before PASV (and EPSV).
              Certain FTP servers, mainly drftpd,  require  this  non-standard
              command  for  directory  listings as well as up and downloads in
              PASV mode.  (Added in 7.20.x)

       --ftp-ssl-ccc
              (FTP) Use CCC (Clear Command Channel)  Shuts  down  the  SSL/TLS
              layer after authenticating. The rest of the control channel com‐
              munication will be unencrypted. This allows NAT routers to  fol‐
              low the FTP transaction. The default mode is passive. See --ftp-
              ssl-ccc-mode for other modes.  (Added in 7.16.1)

       --ftp-ssl-ccc-mode [active/passive]
              (FTP) Use CCC (Clear Command Channel) Sets  the  CCC  mode.  The
              passive  mode  will  not initiate the shutdown, but instead wait
              for the server to do it, and will not reply to the shutdown from
              the server. The active mode initiates the shutdown and waits for
              a reply from the server.  (Added in 7.16.2)

       --ftp-ssl-control
              (FTP) Require SSL/TLS for the FTP  login,  clear  for  transfer.
              Allows  secure  authentication, but non-encrypted data transfers
              for efficiency.  Fails the transfer if the server  doesn't  sup‐
              port SSL/TLS.  (Added in 7.16.0) that can still be used but will
              be removed in a future version.

       --form-string <name=string>
              (HTTP) Similar to --form except that the value  string  for  the
              named  parameter  is used literally. Leading '@' and '<' charac‐
              ters, and the ';type=' string in the value have no special mean‐
              ing. Use this in preference to --form if there's any possibility
              that the string value may accidentally trigger the  '@'  or  '<'
              features of --form.

       -g, --globoff
              This option switches off the "URL globbing parser". When you set
              this option, you can specify URLs that contain the letters  {}[]
              without  having them being interpreted by curl itself. Note that
              these letters are not normal legal URL contents but they  should
              be encoded according to the URI standard.

       -G, --get
              When  used,  this  option  will make all data specified with -d,
              --data or --data-binary to  be  used  in  an  HTTP  GET  request
              instead  of  the  POST request that otherwise would be used. The
              data will be appended to the URL with a '?' separator.

              If used in combination with -I, the POST data  will  instead  be
              appended to the URL with a HEAD request.

              If  this  option  is  used  several times, only the first one is
              used. This is because undoing a GET doesn't make sense, but  you
              should then instead enforce the alternative method you prefer.

       -H, --header <header>
              (HTTP)  Extra  header  to  use  when getting a web page. You may
              specify any number of extra headers. Note that if you should add
              a  custom  header  that has the same name as one of the internal
              ones curl would use, your externally set  header  will  be  used
              instead of the internal one. This allows you to make even trick‐
              ier stuff than curl would normally do. You  should  not  replace
              internally  set  headers  without  knowing  perfectly  well what
              you're doing. Remove an internal header by giving a  replacement
              without  content  on  the  right  side  of  the colon, as in: -H
              "Host:". If you send the custom header with  no-value  then  its
              header  must  be terminated with a semicolon, such as -H "X-Cus‐
              tom-Header;" to send "X-Custom-Header:".

              curl will make sure that each header  you  add/replace  is  sent
              with the proper end-of-line marker, you should thus not add that
              as a part of the header content: do not add newlines or carriage
              returns, they will only mess things up for you.

              See also the -A, --user-agent and -e, --referer options.

              This  option  can  be  used multiple times to add/replace/remove
              multiple headers.

       --hostpubmd5 <md5>
              (SCP/SFTP) Pass a string containing 32 hexadecimal  digits.  The
              string  should  be the 128 bit MD5 checksum of the remote host's
              public key, curl will refuse the connection with the host unless
              the md5sums match. (Added in 7.17.1)

       --ignore-content-length
              (HTTP)  Ignore  the  Content-Length header. This is particularly
              useful for servers running Apache 1.x, which will report  incor‐
              rect Content-Length for files larger than 2 gigabytes.

       -i, --include
              (HTTP)  Include  the  HTTP-header in the output. The HTTP-header
              includes things like server-name, date of  the  document,  HTTP-
              version and more...

       -I, --head
              (HTTP/FTP/FILE) Fetch the HTTP-header only! HTTP-servers feature
              the command HEAD which this uses to get nothing but  the  header
              of  a  document. When used on an FTP or FILE file, curl displays
              the file size and last modification time only.

       --interface <name>
              Perform an operation using a specified interface. You can  enter
              interface  name,  IP address or host name. An example could look
              like:

               curl --interface eth0:1 http://www.netscape.com/

              If this option is used several times, the last one will be used.

       -j, --junk-session-cookies
              (HTTP) When curl is told to read cookies from a given file, this
              option  will  make  it  discard all "session cookies". This will
              basically have the same effect as if a new session  is  started.
              Typical  browsers  always  discard  session cookies when they're
              closed down.

       -J, --remote-header-name
              (HTTP) This option tells the -O, --remote-name option to use the
              server-specified   Content-Disposition   filename   instead   of
              extracting a filename from the URL.

       -k, --insecure
              (SSL) This option explicitly allows curl to  perform  "insecure"
              SSL connections and transfers. All SSL connections are attempted
              to be made secure by using the CA certificate  bundle  installed
              by  default.  This  makes  all connections considered "insecure"
              fail unless -k, --insecure is used.

              See    this    online    resource    for    further     details:
              http://curl.haxx.se/docs/sslcerts.html

       -K, --config <config file>
              Specify  which config file to read curl arguments from. The con‐
              fig file is a text file in which command line arguments  can  be
              written  which  then will be used as if they were written on the
              actual command line. Options and their parameters must be speci‐
              fied  on  the  same  config  file line, separated by whitespace,
              colon, the equals sign or any combination thereof (however,  the
              preferred  separator is the equals sign). If the parameter is to
              contain  whitespace,  the  parameter  must  be  enclosed  within
              quotes. Within double quotes, the following escape sequences are
              available: \\, \", \t, \n, \r and \v. A backslash preceding  any
              other letter is ignored. If the first column of a config line is
              a '#' character, the rest of the line will be treated as a  com‐
              ment.  Only  write  one  option  per physical line in the config
              file.

              Specify the filename to -K, --config as '-' to  make  curl  read
              the file from stdin.

              Note  that  to  be able to specify a URL in the config file, you
              need to specify it using the --url option,  and  not  by  simply
              writing  the  URL  on its own line. So, it could look similar to
              this:

              url = "http://curl.haxx.se/docs/"

              Long option names can optionally be given  in  the  config  file
              without the initial double dashes.

              When curl is invoked, it always (unless -q is used) checks for a
              default config file and uses it if  found.  The  default  config
              file is checked for in the following places in this order:

              1)  curl  tries  to find the "home dir": It first checks for the
              CURL_HOME and then the HOME environment variables. Failing that,
              it  uses getpwuid() on UNIX-like systems (which returns the home
              dir given the current user in your system). On Windows, it  then
              checks for the APPDATA variable, or as a last resort the '%USER‐
              PROFILE%\Application Data'.

              2) On windows, if there is no _curlrc file in the home  dir,  it
              checks for one in the same dir the curl executable is placed. On
              UNIX-like systems, it will simply try to load .curlrc  from  the
              determined home dir.

              # --- Example file ---
              # this is a comment
              url = "curl.haxx.se"
              output = "curlhere.html"
              user-agent = "superagent/1.0"

              # and fetch another URL too
              url = "curl.haxx.se/docs/manpage.html"
              -O
              referer = "http://nowhereatall.com/"
              # --- End of example file ---

              This  option  can be used multiple times to load multiple config
              files.

       --keepalive-time <seconds>
              This option sets the time a  connection  needs  to  remain  idle
              before  sending keepalive probes and the time between individual
              keepalive probes. It is currently effective on operating systems
              offering  the  TCP_KEEPIDLE  and  TCP_KEEPINTVL  socket  options
              (meaning Linux, recent AIX, HP-UX and more). This option has  no
              effect if --no-keepalive is used. (Added in 7.18.0)

              If this option is used several times, the last one will be used.
              If unspecified, the option defaults to 60 seconds.

       --key <key>
              (SSL/SSH) Private key file name. Allows you to provide your pri‐
              vate  key in this separate file. For SSH, if not specified, curl
              tries  the  following  candidates  in  order:   '~/.ssh/id_rsa',
              '~/.ssh/id_dsa', './id_rsa', './id_dsa'.

              If this option is used several times, the last one will be used.

       --key-type <type>
              (SSL)  Private key file type. Specify which type your --key pro‐
              vided private key is. DER, PEM, and ENG are  supported.  If  not
              specified, PEM is assumed.

              If this option is used several times, the last one will be used.

       --krb <level>
              (FTP)  Enable Kerberos authentication and use. The level must be
              entered and should be one of 'clear', 'safe', 'confidential', or
              'private'.  Should  you  use  a  level that is not one of these,
              'private' will instead be used.

              This option requires a library built with  kerberos4  or  GSSAPI
              (GSS-Negotiate) support. This is not very common. Use -V, --ver‐
              sion to see if your curl supports it.

              If this option is used several times, the last one will be used.

       -l, --list-only
              (FTP) When listing an FTP directory, this switch forces a  name-
              only  view.   Especially useful if you want to machine-parse the
              contents of an FTP directory since  the  normal  directory  view
              doesn't use a standard look or format.

              This  option  causes  an  FTP NLST command to be sent.  Some FTP
              servers list only files in their response to NLST; they  do  not
              include subdirectories and symbolic links.


       -L, --location
              (HTTP/HTTPS)  If  the server reports that the requested page has
              moved to a different location (indicated with a Location: header
              and  a  3XX  response code), this option will make curl redo the
              request on the new place. If used together with -i, --include or
              -I, --head, headers from all requested pages will be shown. When
              authentication is used, curl only sends its credentials  to  the
              initial  host.  If a redirect takes curl to a different host, it
              won't be able to intercept the user+password. See  also  --loca‐
              tion-trusted  on how to change this. You can limit the amount of
              redirects to follow by using the --max-redirs option.

              When curl follows a redirect and the request is not a plain  GET
              (for example POST or PUT), it will do the following request with
              a GET if the HTTP response was 301, 302, or 303. If the response
              code  was  any  other  3xx code, curl will re-send the following
              request using the same unmodified method.

       --libcurl <file>
              Append this option to any ordinary curl command  line,  and  you
              will  get a libcurl-using C source code written to the file that
              does the equivalent of what your command-line operation does!

              If this option is used several times, the last given  file  name
              will be used. (Added in 7.16.1)

       --limit-rate <speed>
              Specify  the  maximum  transfer  rate you want curl to use. This
              feature is useful if you have a limited pipe and you'd like your
              transfer not to use your entire bandwidth.

              The  given speed is measured in bytes/second, unless a suffix is
              appended.  Appending 'k' or 'K' will count the number  as  kilo‐
              bytes,  'm'  or M' makes it megabytes, while 'g' or 'G' makes it
              gigabytes. Examples: 200K, 3m and 1G.

              The given rate is the average speed counted  during  the  entire
              transfer. It means that curl might use higher transfer speeds in
              short bursts, but over time it uses no more than the given rate.

              If you also use the -Y, --speed-limit option, that  option  will
              take precedence and might cripple the rate-limiting slightly, to
              help keeping the speed-limit logic working.

              If this option is used several times, the last one will be used.

       --local-port <num>[-num]
              Set a preferred number or range of local port numbers to use for
              the  connection(s).   Note  that  port  numbers  by nature are a
              scarce resource that will be busy at times so setting this range
              to something too narrow might cause unnecessary connection setup
              failures. (Added in 7.15.2)

       --location-trusted
              (HTTP/HTTPS) Like -L, --location, but  will  allow  sending  the
              name + password to all hosts that the site may redirect to. This
              may or may not introduce a security breach if the site redirects
              you  to  a  site  to  which you'll send your authentication info
              (which is plaintext in the case of HTTP Basic authentication).

       -m, --max-time <seconds>
              Maximum time in seconds that you allow the  whole  operation  to
              take.   This is useful for preventing your batch jobs from hang‐
              ing for hours due to slow networks or  links  going  down.   See
              also the --connect-timeout option.

              If this option is used several times, the last one will be used.

       --mail-auth <address>
              (SMTP)  Specify  a  single address. This will be used to specify
              the authentication address (identity)  of  a  submitted  message
              that is being relayed to another server.

              (Added in 7.25.0)

       --mail-from <address>
              (SMTP)  Specify  a single address that the given mail should get
              sent from.

              (Added in 7.20.0)

       --max-filesize <bytes>
              Specify the maximum size (in bytes) of a file  to  download.  If
              the  file requested is larger than this value, the transfer will
              not start and curl will return with exit code 63.

              NOTE: The file size is not always known prior to  download,  and
              for such files this option has no effect even if the file trans‐
              fer ends up being larger than this given  limit.  This  concerns
              both FTP and HTTP transfers.

       --mail-rcpt <address>
              (SMTP)  Specify  a single address that the given mail should get
              sent to. This option can be used multiple times to specify  many
              recipients.

              (Added in 7.20.0)

       --max-redirs <num>
              Set  maximum  number  of  redirection-followings allowed. If -L,
              --location is used, this option can be used to prevent curl from
              following  redirections  "in absurdum". By default, the limit is
              set to 50 redirections. Set this option to -1 to make it  limit‐
              less.

              If this option is used several times, the last one will be used.

       --metalink
              This  option  can  tell curl to parse and process a given URI as
              Metalink file (both version 3 and 4 (RFC  5854)  are  supported)
              and  make use of the mirrors listed within for failover if there
              are errors (such as the file or server not being available).  It
              will  also  verify  the hash of the file after the download com‐
              pletes. The Metalink file itself is downloaded and processed  in
              memory and not stored in the local file system.

              Example to use a remote Metalink file:

              curl --metalink http://www.example.com/example.metalink

              To use a Metalink file in the local file system, use FILE proto‐
              col (file://):

              curl --metalink file://example.metalink

              Please note that if FILE protocol is disabled, there is  no  way
              to  use  a local Metalink file at the time of this writing. Also
              note  that  if  --metalink  and  --include  are  used  together,
              --include  will be ignored. This is because including headers in
              the response will break Metalink parser and if the  headers  are
              included in the file described in Metalink file, hash check will
              fail.

              (Added in 7.27.0, if built against the libmetalink library.)

       -n, --netrc
              Makes curl scan the .netrc  (_netrc  on  Windows)  file  in  the
              user's home directory for login name and password. This is typi‐
              cally used for FTP on UNIX. If used with HTTP, curl will  enable
              user  authentication.  See netrc(4) or ftp(1) for details on the
              file format. Curl will not complain if that  file  doesn't  have
              the  right permissions (it should not be either world- or group-
              readable). The environment variable "HOME" is used to  find  the
              home directory.

              A  quick  and  very  simple  example of how to setup a .netrc to
              allow curl to FTP to the machine host.domain.com with user  name
              'myself' and password 'secret' should look similar to:

              machine host.domain.com login myself password secret

       -N, --no-buffer
              Disables the buffering of the output stream. In normal work sit‐
              uations, curl will use a standard buffered  output  stream  that
              will have the effect that it will output the data in chunks, not
              necessarily exactly when the data arrives.   Using  this  option
              will disable that buffering.

              Note  that  this  is the negated option name documented. You can
              thus use --buffer to enforce the buffering.

       --netrc-file
              This option is similar to --netrc, except that you  provide  the
              path  (absolute  or relative) to the netrc file that Curl should
              use.  You can only specify one netrc  file  per  invocation.  If
              several  --netrc-file  options  are  provided, only the last one
              will be used.  (Added in 7.21.5)

              This option overrides any use of --netrc as  they  are  mutually
              exclusive.  It will also abide by --netrc-optional if specified.


       --netrc-optional
              Very  similar to --netrc, but this option makes the .netrc usage
              optional and not mandatory as the --netrc option does.


       --negotiate
              (HTTP) Enables GSS-Negotiate authentication.  The  GSS-Negotiate
              method was designed by Microsoft and is used in their web appli‐
              cations. It is  primarily  meant  as  a  support  for  Kerberos5
              authentication but may be also used along with another authenti‐
              cation method. For more information see IETF draft draft-brezak-
              spnego-http-04.txt.

              If  you  want to enable Negotiate for your proxy authentication,
              then use --proxy-negotiate.

              This option requires a library built with GSSAPI  support.  This
              is  not  very  common.  Use -V, --version to see if your version
              supports GSS-Negotiate.

              When using this option, you must also provide a fake -u,  --user
              option  to  activate the authentication code properly. Sending a
              '-u :' is enough as the user  name  and  password  from  the  -u
              option aren't actually used.

              If  this  option  is  used  several times, only the first one is
              used.

       --no-keepalive
              Disables the use of keepalive messages on the TCP connection, as
              by default curl enables them.

              Note  that  this  is the negated option name documented. You can
              thus use --keepalive to enforce keepalive.

       --no-sessionid
              (SSL) Disable curl's use of SSL session-ID caching.  By  default
              all  transfers are done using the cache. Note that while nothing
              should ever get hurt by attempting  to  reuse  SSL  session-IDs,
              there seem to be broken SSL implementations in the wild that may
              require you to disable this in order for you to succeed.  (Added
              in 7.16.0)

              Note  that  this  is the negated option name documented. You can
              thus use --sessionid to enforce session-ID caching.

       --noproxy <no-proxy-list>
              Comma-separated list of hosts which do not use a proxy,  if  one
              is  specified.  The only wildcard is a single * character, which
              matches all hosts, and effectively disables the proxy. Each name
              in  this  list  is matched as either a domain which contains the
              hostname, or the hostname itself. For example,  local.com  would
              match   local.com,  local.com:80,  and  www.local.com,  but  not
              www.notlocal.com.  (Added in 7.19.4).

       --ntlm (HTTP) Enables  NTLM  authentication.  The  NTLM  authentication
              method was designed by Microsoft and is used by IIS web servers.
              It is a proprietary protocol, reverse-engineered by clever  peo‐
              ple and implemented in curl based on their efforts. This kind of
              behavior should not be endorsed, you should  encourage  everyone
              who  uses  NTLM to switch to a public and documented authentica‐
              tion method instead, such as Digest.

              If you want to enable NTLM for your proxy  authentication,  then
              use --proxy-ntlm.

              This  option  requires a library built with SSL support. Use -V,
              --version to see if your curl supports NTLM.

              If this option is used several times,  only  the  first  one  is
              used.

       -o, --output <file>
              Write output to <file> instead of stdout. If you are using {} or
              [] to fetch multiple documents, you can use '#'  followed  by  a
              number  in  the <file> specifier. That variable will be replaced
              with the current string for the URL being fetched. Like in:

                curl http://{one,two}.site.com -o "file_#1.txt"

              or use several variables like:

                curl http://{site,host}.host[1-5].com -o "#1_#2"

              You may use this option as many times as the number of URLs  you
              have.

              See  also  the --create-dirs option to create the local directo‐
              ries dynamically. Specifying the output as '-' (a  single  dash)
              will force the output to be done to stdout.

       -O, --remote-name
              Write  output to a local file named like the remote file we get.
              (Only the file part of the remote file is used, the path is  cut
              off.)

              The  remote  file  name  to use for saving is extracted from the
              given URL, nothing else.

              Consequentially, the file will be saved in the  current  working
              directory.  If you want the file saved in a different directory,
              make sure you change current working directory before you invoke
              curl with the -O, --remote-name flag!

              You  may use this option as many times as the number of URLs you
              have.

       -p, --proxytunnel
              When an HTTP proxy is used (-x, --proxy), this option will cause
              non-HTTP  protocols  to  attempt  to  tunnel  through  the proxy
              instead of merely using it to do HTTP-like operations. The  tun‐
              nel  approach  is  made  with the HTTP proxy CONNECT request and
              requires that the proxy allows direct connect to the remote port
              number curl wants to tunnel through to.

       -P, --ftp-port <address>
              (FTP)  Reverses  the  default initiator/listener roles when con‐
              necting with FTP. This switch makes curl  use  active  mode.  In
              practice,  curl  then  tells  the  server to connect back to the
              client's specified address and port, while passive mode asks the
              server  to  setup  an  IP address and port for it to connect to.
              <address> should be one of:

              interface
                     i.e "eth0" to specify which interface's  IP  address  you
                     want to use (Unix only)

              IP address
                     i.e "192.168.10.1" to specify the exact IP address

              host name
                     i.e "my.host.domain" to specify the machine

              -      make  curl  pick the same IP address that is already used
                     for the control connection

       If this option is used several times, the last one will be  used.  Dis‐
       able  the  use  of PORT with --ftp-pasv. Disable the attempt to use the
       EPRT command instead of PORT by using --disable-eprt.  EPRT  is  really
       PORT++.

       Starting in 7.19.5, you can append ":[start]-[end]" to the right of the
       address, to tell curl what TCP port range to use. That means you  spec‐
       ify  a  port  range,  from  a lower to a higher number. A single number
       works as well, but do note that it increases the risk of failure  since
       the port may not be available.

       --pass <phrase>
              (SSL/SSH) Passphrase for the private key

              If this option is used several times, the last one will be used.

       --post301
              (HTTP)  Tells  curl  to  respect RFC 2616/10.3.2 and not convert
              POST requests into GET requests when following a  301  redirect‐
              ion.  The  non-RFC  behaviour  is ubiquitous in web browsers, so
              curl does the conversion by  default  to  maintain  consistency.
              However, a server may require a POST to remain a POST after such
              a redirection. This option is meaningful  only  when  using  -L,
              --location (Added in 7.17.1)

       --post302
              (HTTP)  Tells  curl  to  respect RFC 2616/10.3.2 and not convert
              POST requests into GET requests when following a  302  redirect‐
              ion.  The  non-RFC  behaviour  is ubiquitous in web browsers, so
              curl does the conversion by  default  to  maintain  consistency.
              However, a server may require a POST to remain a POST after such
              a redirection. This option is meaningful  only  when  using  -L,
              --location (Added in 7.19.1)

       --post303
              (HTTP)  Tells  curl  to  respect RFC 2616/10.3.2 and not convert
              POST requests into GET requests when following a  303  redirect‐
              ion.  The  non-RFC  behaviour  is ubiquitous in web browsers, so
              curl does the conversion by  default  to  maintain  consistency.
              However, a server may require a POST to remain a POST after such
              a redirection. This option is meaningful  only  when  using  -L,
              --location (Added in 7.26.0)

       --proto <protocols>
              Tells   curl  to  use  the  listed  protocols  for  its  initial
              retrieval. Protocols are evaluated left to right, are comma sep‐
              arated,  and  are each a protocol name or 'all', optionally pre‐
              fixed by zero or more modifiers. Available modifiers are:

              +  Permit this protocol in addition to protocols already permit‐
                 ted (this is the default if no modifier is used).

              -  Deny  this  protocol,  removing it from the list of protocols
                 already permitted.

              =  Permit only this protocol (ignoring the list already  permit‐
                 ted),  though  subject  to  later  modification by subsequent
                 entries in the comma separated list.

              For example:

              --proto -ftps  uses the default protocols, but disables ftps

              --proto -all,https,+http
                             only enables http and https

              --proto =http,https
                             also only enables http and https

              Unknown protocols produce a  warning.  This  allows  scripts  to
              safely  rely on being able to disable potentially dangerous pro‐
              tocols, without relying upon support  for  that  protocol  being
              built into curl to avoid an error.

              This option can be used multiple times, in which case the effect
              is the same as concatenating the protocols into one instance  of
              the option.

              (Added in 7.20.2)

       --proto-redir <protocols>
              Tells  curl  to  use  the listed protocols after a redirect. See
              --proto for how protocols are represented.

              (Added in 7.20.2)

       --proxy-anyauth
              Tells curl to pick a suitable authentication method when  commu‐
              nicating  with  the  given  proxy.  This  might  cause  an extra
              request/response round-trip. (Added in 7.13.2)

       --proxy-basic
              Tells curl to use HTTP Basic authentication  when  communicating
              with the given proxy. Use --basic for enabling HTTP Basic with a
              remote host. Basic is the  default  authentication  method  curl
              uses with proxies.

       --proxy-digest
              Tells  curl to use HTTP Digest authentication when communicating
              with the given proxy. Use --digest for enabling HTTP Digest with
              a remote host.

       --proxy-negotiate
              Tells curl to use HTTP Negotiate authentication when communicat‐
              ing with the given proxy.  Use  --negotiate  for  enabling  HTTP
              Negotiate with a remote host. (Added in 7.17.1)

       --proxy-ntlm
              Tells  curl  to  use HTTP NTLM authentication when communicating
              with the given proxy. Use --ntlm for enabling NTLM with a remote
              host.

       --proxy1.0 <proxyhost[:port]>
              Use  the  specified  HTTP  1.0  proxy. If the port number is not
              specified, it is assumed at port 1080.

              The only difference between this and the HTTP proxy option  (-x,
              --proxy), is that attempts to use CONNECT through the proxy will
              specify an HTTP 1.0 protocol instead of the default HTTP 1.1.

       --pubkey <key>
              (SSH) Public key file name. Allows you to  provide  your  public
              key in this separate file.

              If this option is used several times, the last one will be used.

              (As of 7.39.0, curl attempts to automatically extract the public
              key from the private key file, so passing this option is  gener‐
              ally not required. Note that this public key extraction requires
              libcurl to be linked against a copy of libssh2 1.2.8  or  higher
              that is itself linked against OpenSSL.)

       -q     If  used  as the first parameter on the command line, the curlrc
              config file will not be read and used. See the -K, --config  for
              details on the default config file search path.

       -Q, --quote <command>
              (FTP/SFTP)  Send  an arbitrary command to the remote FTP or SFTP
              server. Quote commands are sent BEFORE the transfer takes  place
              (just  after  the  initial PWD command in an FTP transfer, to be
              exact). To make commands take place after a successful transfer,
              prefix  them  with  a  dash '-'.  To make commands be sent after
              curl has changed the working directory, just before the transfer
              command(s),  prefix  the  command  with a '+' (this is only sup‐
              ported for FTP). You may specify any number of commands. If  the
              server returns failure for one of the commands, the entire oper‐
              ation will be aborted. You must send syntactically  correct  FTP
              commands  as  RFC 959 defines to FTP servers, or one of the com‐
              mands listed below to SFTP servers.  This  option  can  be  used
              multiple  times. When speaking to an FTP server, prefix the com‐
              mand with an asterisk (*) to make curl continue even if the com‐
              mand fails as by default curl will stop at first failure.

              SFTP  is a binary protocol. Unlike for FTP, curl interprets SFTP
              quote commands itself before sending them to the  server.   File
              names may be quoted shell-style to embed spaces or special char‐
              acters.  Following is the list of all supported SFTP quote  com‐
              mands:

              chgrp group file
                     The  chgrp command sets the group ID of the file named by
                     the file operand to the group ID specified by  the  group
                     operand. The group operand is a decimal integer group ID.

              chmod mode file
                     The  chmod  command  modifies  the  file mode bits of the
                     specified file. The mode operand is an octal integer mode
                     number.

              chown user file
                     The chown command sets the owner of the file named by the
                     file operand to the user ID specified by the  user  oper‐
                     and. The user operand is a decimal integer user ID.

              ln source_file target_file
                     The ln and symlink commands create a symbolic link at the
                     target_file location pointing to  the  source_file  loca‐
                     tion.

              mkdir directory_name
                     The  mkdir  command  creates  the  directory named by the
                     directory_name operand.

              pwd    The pwd command returns the absolute pathname of the cur‐
                     rent working directory.

              rename source target
                     The rename command renames the file or directory named by
                     the source operand to the destination path named  by  the
                     target operand.

              rm file
                     The rm command removes the file specified by the file op‐
                     erand.

              rmdir directory
                     The rmdir command removes the directory  entry  specified
                     by the directory operand, provided it is empty.

              symlink source_file target_file
                     See ln.

       -r, --range <range>
              (HTTP/FTP/SFTP/FILE)  Retrieve a byte range (i.e a partial docu‐
              ment) from a HTTP/1.1, FTP or  SFTP  server  or  a  local  FILE.
              Ranges can be specified in a number of ways.

              0-499     specifies the first 500 bytes

              500-999   specifies the second 500 bytes

              -500      specifies the last 500 bytes

              9500-     specifies the bytes from offset 9500 and forward

              0-0,-1    specifies the first and last byte only(*)(H)

              500-700,600-799
                        specifies 300 bytes from offset 500(H)

              100-199,500-599
                        specifies two separate 100-byte ranges(*)(H)

       (*)  =  NOTE  that this will cause the server to reply with a multipart
       response!

       Only digit characters (0-9) are valid in the 'start' and 'stop'  fields
       of  the 'start-stop' range syntax. If a non-digit character is given in
       the range, the server's response will be unspecified, depending on  the
       server's configuration.

       You  should  also  be aware that many HTTP/1.1 servers do not have this
       feature enabled, so that when  you  attempt  to  get  a  range,  you'll
       instead get the whole document.

       FTP  and SFTP range downloads only support the simple 'start-stop' syn‐
       tax (optionally with one of the numbers omitted). FTP  use  depends  on
       the extended FTP command SIZE.

       If this option is used several times, the last one will be used.

       -R, --remote-time
              When  used,  this will make curl attempt to figure out the time‐
              stamp of the remote file, and if  that  is  available  make  the
              local file get that same timestamp.

       --random-file <file>
              (SSL) Specify the path name to file containing what will be con‐
              sidered as random data. The data is  used  to  seed  the  random
              engine for SSL connections.  See also the --egd-file option.

       --raw  (HTTP) When used, it disables all internal HTTP decoding of con‐
              tent or transfer encodings and  instead  makes  them  passed  on
              unaltered, raw. (Added in 7.16.2)

       --remote-name-all
              This  option changes the default action for all given URLs to be
              dealt with as if -O, --remote-name were used for each one. So if
              you want to disable that for a specific URL after --remote-name-
              all has been used, you must  use  "-o  -"  or  --no-remote-name.
              (Added in 7.19.0)

       --resolve <host:port:address>
              Provide  a  custom  address  for  a specific host and port pair.
              Using this, you can make the curl requests(s)  use  a  specified
              address  and  prevent the otherwise normally resolved address to
              be used. Consider it a sort of /etc/hosts  alternative  provided
              on  the  command line. The port number should be the number used
              for the specific protocol the host will be used  for.  It  means
              you  need several entries if you want to provide address for the
              same host but different ports.

              This option can be used many times to add  many  host  names  to
              resolve.

              (Added in 7.21.3)

       --retry <num>
              If  a  transient  error is returned when curl tries to perform a
              transfer, it will retry this number of times before  giving  up.
              Setting  the  number to 0 makes curl do no retries (which is the
              default). Transient error means either: a timeout,  an  FTP  4xx
              response code or an HTTP 5xx response code.

              When  curl  is about to retry a transfer, it will first wait one
              second and then for all forthcoming retries it will  double  the
              waiting  time until it reaches 10 minutes which then will be the
              delay between the rest of the retries.  By  using  --retry-delay
              you   disable  this  exponential  backoff  algorithm.  See  also
              --retry-max-time to limit the total time  allowed  for  retries.
              (Added in 7.12.3)

              If this option is used several times, the last one will be used.

       --retry-delay <seconds>
              Make  curl  sleep  this  amount of time before each retry when a
              transfer has failed with  a  transient  error  (it  changes  the
              default  backoff time algorithm between retries). This option is
              only interesting if --retry is also used. Setting this delay  to
              zero  will  make  curl  use the default backoff time.  (Added in
              7.12.3)

              If this option is used several times, the last one will be used.

       --retry-max-time <seconds>
              The retry timer is reset  before  the  first  transfer  attempt.
              Retries will be done as usual (see --retry) as long as the timer
              hasn't reached this given limit. Notice that if the timer hasn't
              reached  the  limit, the request will be made and while perform‐
              ing, it may take longer than this given time period. To limit  a
              single  request´s  maximum  time,  use -m, --max-time.  Set this
              option to zero to not timeout retries. (Added in 7.12.3)

              If this option is used several times, the last one will be used.

       -s, --silent
              Silent or quiet mode. Don't show progress meter  or  error  mes‐
              sages.  Makes Curl mute.

       -S, --show-error
              When  used  with  -s  it  makes curl show an error message if it
              fails.

       --ssl  (FTP, POP3, IMAP, SMTP) Try to use SSL/TLS for  the  connection.
              Reverts to a non-secure connection if the server doesn't support
              SSL/TLS.  See also --ftp-ssl-control and --ssl-reqd for  differ‐
              ent levels of encryption required. (Added in 7.20.0)

              This  option  was formerly known as --ftp-ssl (Added in 7.11.0).
              That option name can still be used but  will  be  removed  in  a
              future version.

       --ssl-reqd
              (FTP,  POP3,  IMAP,  SMTP)  Require  SSL/TLS for the connection.
              Terminates the connection if the server doesn't support SSL/TLS.
              (Added in 7.20.0)

              This  option  was  formerly  known  as  --ftp-ssl-reqd (added in
              7.15.5). That option name can still be used but will be  removed
              in a future version.

       --ssl-allow-beast
              (SSL)  This option tells curl to not work around a security flaw
              in the SSL3 and TLS1.0 protocols known as BEAST.  If this option
              isn't  used,  the  SSL layer may use work-arounds known to cause
              interoperability problems with some older  SSL  implementations.
              WARNING: this option loosens the SSL security, and by using this
              flag you ask for exactly that.  (Added in 7.25.0)

       --socks4 <host[:port]>
              Use the specified SOCKS4 proxy. If the port number is not speci‐
              fied, it is assumed at port 1080. (Added in 7.15.2)

              This  option  overrides any previous use of -x, --proxy, as they
              are mutually exclusive.

              Since 7.21.7, this option is superfluous since you can specify a
              socks4 proxy with -x, --proxy using a socks4:// protocol prefix.

              If this option is used several times, the last one will be used.

       --socks4a <host[:port]>
              Use the specified SOCKS4a proxy. If the port number is not spec‐
              ified, it is assumed at port 1080. (Added in 7.18.0)

              This option overrides any previous use of -x, --proxy,  as  they
              are mutually exclusive.

              Since 7.21.7, this option is superfluous since you can specify a
              socks4a proxy with -x, --proxy using a socks4a:// protocol  pre‐
              fix.

              If this option is used several times, the last one will be used.

       --socks5-basic
              Tells curl to use username/password authentication when connect‐
              ing to a SOCKS5 proxy.  The username/password authentication  is
              enabled  by  default.   Use  --socks5-gssapi  to  force  GSS-API
              authentication to SOCKS5 proxies.  (Added in 7.55.0)

       --socks5-gssapi
              Tells curl to use GSS-API authentication when  connecting  to  a
              SOCKS5  proxy.  The GSS-API authentication is enabled by default
              (if curl is compiled with GSS-API support).  Use  --socks5-basic
              to  force  username/password  authentication  to SOCKS5 proxies.
              (Added in 7.55.0)

       --socks5-hostname <host[:port]>
              Use the specified SOCKS5 proxy (and let the  proxy  resolve  the
              host  name).  If the port number is not specified, it is assumed
              at port 1080. (Added in 7.18.0)

              This option overrides any previous use of -x, --proxy,  as  they
              are mutually exclusive.

              Since 7.21.7, this option is superfluous since you can specify a
              socks5 hostname proxy with -x, --proxy using a socks5h:// proto‐
              col prefix.

              If this option is used several times, the last one will be used.
              (This option was  previously  wrongly  documented  and  used  as
              --socks without the number appended.)

       --socks5 <host[:port]>
              Use  the  specified  SOCKS5  proxy  -  but resolve the host name
              locally. If the port number is not specified, it is  assumed  at
              port 1080.

              This  option  overrides any previous use of -x, --proxy, as they
              are mutually exclusive.

              Since 7.21.7, this option is superfluous since you can specify a
              socks5 proxy with -x, --proxy using a socks5:// protocol prefix.

              If this option is used several times, the last one will be used.
              (This option was  previously  wrongly  documented  and  used  as
              --socks without the number appended.)

              This  option (as well as --socks4) does not work with IPV6, FTPS
              or LDAP.

       --socks5-gssapi-service <servicename>
              The default service name for a socks server is rcmd/server-fqdn.
              This option allows you to change it.

              Examples:   --socks5  proxy-name  --socks5-gssapi-service  sockd
              would use sockd/proxy-name --socks5 proxy-name  --socks5-gssapi-
              service  sockd/real-name  would  use  sockd/real-name  for cases
              where the proxy-name does not match the principal name.   (Added
              in 7.19.4).

       --socks5-gssapi-nec
              As  part  of the gssapi negotiation a protection mode is negoti‐
              ated. RFC 1961 says in section 4.3/4.4 it should  be  protected,
              but  the  NEC  reference  implementation  does  not.  The option
              --socks5-gssapi-nec allows the unprotected exchange of the  pro‐
              tection mode negotiation. (Added in 7.19.4).

       --stderr <file>
              Redirect  all writes to stderr to the specified file instead. If
              the file name is a plain '-', it is instead written to stdout.

              If this option is used several times, the last one will be used.

       -t, --telnet-option <OPT=val>
              Pass options to the telnet protocol. Supported options are:

              TTYPE=<term> Sets the terminal type.

              XDISPLOC=<X display> Sets the X display location.

              NEW_ENV=<var,val> Sets an environment variable.

       -T, --upload-file <file>
              This transfers the specified local file to the  remote  URL.  If
              there is no file part in the specified URL, Curl will append the
              local file name. NOTE that you must use a trailing / on the last
              directory  to really prove to Curl that there is no file name or
              curl will think that your last directory name is the remote file
              name to use. That will most likely cause the upload operation to
              fail. If this is used on an HTTP(S) server, the PUT command will
              be used.

              Use  the file name "-" (a single dash) to use stdin instead of a
              given file.  Alternately, the file name "."  (a  single  period)
              may  be  specified  instead  of "-" to use stdin in non-blocking
              mode to  allow  reading  server  output  while  stdin  is  being
              uploaded.

              You can specify one -T for each URL on the command line. Each -T
              + URL pair specifies what to upload and to where. curl also sup‐
              ports "globbing" of the -T argument, meaning that you can upload
              multiple files to a single URL by using the  same  URL  globbing
              style supported in the URL, like this:

              curl -T "{file1,file2}" http://www.uploadtothissite.com

              or even

              curl -T "img[1-1000].png" ftp://ftp.picturemania.com/upload/

       --tcp-nodelay
              Turn  on the TCP_NODELAY option. See the curl_easy_setopt(3) man
              page for details about this option. (Added in 7.11.2)

       --tftp-blksize <value>
              (TFTP) Set TFTP BLKSIZE option (must be >512). This is the block
              size that curl will try to use when transferring data to or from
              a TFTP server. By default 512 bytes will be used.

              If this option is used several times, the last one will be used.

              (Added in 7.20.0)

       --tlsauthtype <authtype>
              Set TLS  authentication  type.  Currently,  the  only  supported
              option  is  "SRP",  for  TLS-SRP  (RFC  5054).  If --tlsuser and
              --tlspassword are specified but --tlsauthtype is not, then  this
              option  defaults to "SRP".  This option works only if the under‐
              lying libcurl is built  with  TLS-SRP  support,  which  requires
              OpenSSL or GnuTLS with TLS-SRP support.  (Added in 7.21.4)

       --tlspassword <password>
              Set  password  for use with the TLS authentication method speci‐
              fied with --tlsauthtype. Requires that --tlsuser  also  be  set.
              (Added in 7.21.4)

       --tlsuser <user>
              Set  username  for use with the TLS authentication method speci‐
              fied with --tlsauthtype. Requires  that  --tlspassword  also  be
              set.  (Added in 7.21.4)

       --tlsv1.0
              (SSL) Forces curl to use TLS version 1.0 when negotiating with a
              remote TLS server.  (Added in 7.34.0)

       --tlsv1.1
              (SSL) Forces curl to use TLS version 1.1 when negotiating with a
              remote TLS server.  (Added in 7.34.0)

       --tlsv1.2
              (SSL) Forces curl to use TLS version 1.2 when negotiating with a
              remote TLS server.  (Added in 7.34.0)

       --tlsv1.3
              (SSL) Forces curl to use TLS version 1.3 when negotiating with a
              remote TLS server.  (Added in 7.52.0)

       --tls-max <VERSION>
              (SSL) VERSION defines maximum supported TLS version. The minimum
              acceptable version  is  set  by  tlsv1.0,  tlsv1.1,  tlsv1.2  or
              tlsv1.3.


              default
                     Use up to recommended TLS version.

              1.0    Use up to TLSv1.0.

              1.1    Use up to TLSv1.1.

              1.2    Use up to TLSv1.2.

              1.3    Use up to TLSv1.3.

       See also --tlsv1.0 and --tlsv1.1 and --tlsv1.2 and --tlsv1.3.  Added in
       7.54.0.

       --tr-encoding
              (HTTP) Request a compressed Transfer-Encoding response using one
              of  the  algorithms curl supports, and uncompress the data while
              receiving it.

              (Added in 7.21.6)

       --trace <file>
              Enables a full trace dump of all  incoming  and  outgoing  data,
              including descriptive information, to the given output file. Use
              "-" as filename to have the output sent to stdout.

              This option overrides previous uses of -v, --verbose or --trace-
              ascii.

              If this option is used several times, the last one will be used.

       --trace-ascii <file>
              Enables  a  full  trace  dump of all incoming and outgoing data,
              including descriptive information, to the given output file. Use
              "-" as filename to have the output sent to stdout.

              This is very similar to --trace, but leaves out the hex part and
              only shows the ASCII part of the dump. It makes  smaller  output
              that might be easier to read for untrained humans.

              This option overrides previous uses of -v, --verbose or --trace.

              If this option is used several times, the last one will be used.

       --trace-time
              Prepends  a  time  stamp to each trace or verbose line that curl
              displays.  (Added in 7.14.0)

       --unix-socket <path>
              (HTTP) Connect through this UNIX domain socket, instead of using
              the network. (Added in 7.40.0)

       -u, --user <user:password>
              Specify the user name and password to use for server authentica‐
              tion. Overrides -n, --netrc and --netrc-optional.

              If you just give the user name (without entering a  colon)  curl
              will prompt for a password.

              If  you  use an SSPI-enabled curl binary and do NTLM authentica‐
              tion, you can force curl to pick up the user name  and  password
              from  your  environment by simply specifying a single colon with
              this option: "-u :".

              If this option is used several times, the last one will be used.

       -U, --proxy-user <user:password>
              Specify the user name and password to use for proxy  authentica‐
              tion.

              If  you  use an SSPI-enabled curl binary and do NTLM authentica‐
              tion, you can force curl to pick up the user name  and  password
              from  your  environment by simply specifying a single colon with
              this option: "-U :".

              If this option is used several times, the last one will be used.

       --url <URL>
              Specify a URL to fetch. This option is  mostly  handy  when  you
              want to specify URL(s) in a config file.

              This  option  may  be used any number of times. To control where
              this URL is written, use the -o, --output or the  -O,  --remote-
              name options.

       -v, --verbose
              Makes  the  fetching  more  verbose/talkative. Mostly useful for
              debugging. A line starting with '>' means "header data" sent  by
              curl, '<' means "header data" received by curl that is hidden in
              normal cases, and a line starting with '*' means additional info
              provided by curl.

              Note  that  if  you  only  want  HTTP headers in the output, -i,
              --include might be the option you're looking for.

              If you think this option still doesn't give you enough  details,
              consider using --trace or --trace-ascii instead.

              This option overrides previous uses of --trace-ascii or --trace.

              Use -s, --silent to make curl quiet.

       -w, --write-out <format>
              Defines what to display on stdout after a completed and success‐
              ful operation. The format is a string  that  may  contain  plain
              text mixed with any number of variables. The string can be spec‐
              ified as "string", to get read from a particular file you  spec‐
              ify  it  "@filename"  and  to  tell curl to read the format from
              stdin you write "@-".

              The variables present in the output format will  be  substituted
              by  the  value or text that curl thinks fit, as described below.
              All variables are specified as %{variable_name} and to output  a
              normal  % you just write them as %%. You can output a newline by
              using \n, a carriage return with \r and a tab space with \t.

              NOTE: The %-symbol is a special symbol in the win32-environment,
              where  all  occurrences  of  %  must  be doubled when using this
              option.

              The variables available are:

              content_type   The Content-Type of the  requested  document,  if
                             there was any.

              filename_effective
                             The  ultimate  filename  that curl writes out to.
                             This is only meaningful if curl is told to  write
                             to  a  file  with  the  --remote-name or --output
                             option. It's most useful in combination with  the
                             --remote-header-name option. (Added in 7.25.1)

              ftp_entry_path The initial path curl ended up in when logging on
                             to the remote FTP server. (Added in 7.15.4)

              http_code      The numerical response code that was found in the
                             last  retrieved  HTTP(S)  or  FTP(s) transfer. In
                             7.18.2 the alias response_code was added to  show
                             the same info.

              http_connect   The  numerical  code  that  was found in the last
                             response  (from  a  proxy)  to  a  curl   CONNECT
                             request. (Added in 7.12.4)

              local_ip       The  IP  address  of  the  local  end of the most
                             recently done connection - can be either IPv4  or
                             IPv6 (Added in 7.29.0)

              local_port     The  local  port number of the most recently done
                             connection (Added in 7.29.0)

              num_connects   Number of new connects made in the recent  trans‐
                             fer. (Added in 7.12.3)

              num_redirects  Number  of  redirects  that  were followed in the
                             request. (Added in 7.12.3)

              redirect_url   When an HTTP request was made without -L to  fol‐
                             low redirects, this variable will show the actual
                             URL a redirect  would  take  you  to.  (Added  in
                             7.18.2)

              remote_ip      The  remote  IP address of the most recently done
                             connection - can be either IPv4 or IPv6 (Added in
                             7.29.0)

              remote_port    The  remote port number of the most recently done
                             connection (Added in 7.29.0)

              size_download  The total amount of bytes that were downloaded.

              size_header    The total amount of bytes of the downloaded head‐
                             ers.

              size_request   The  total  amount of bytes that were sent in the
                             HTTP request.

              size_upload    The total amount of bytes that were uploaded.

              speed_download The average download speed that curl measured for
                             the complete download. Bytes per second.

              speed_upload   The  average  upload speed that curl measured for
                             the complete upload. Bytes per second.

              ssl_verify_result
                             The result of the SSL peer certificate  verifica‐
                             tion that was requested. 0 means the verification
                             was successful. (Added in 7.19.0)

              time_appconnect
                             The time, in seconds,  it  took  from  the  start
                             until  the  SSL/SSH/etc  connect/handshake to the
                             remote host was completed. (Added in 7.19.0)

              time_connect   The time, in seconds,  it  took  from  the  start
                             until  the  TCP  connect  to  the remote host (or
                             proxy) was completed.

              time_namelookup
                             The time, in seconds,  it  took  from  the  start
                             until the name resolving was completed.

              time_pretransfer
                             The  time,  in  seconds,  it  took from the start
                             until the file transfer was just about to  begin.
                             This includes all pre-transfer commands and nego‐
                             tiations that are specific to the particular pro‐
                             tocol(s) involved.

              time_redirect  The time, in seconds, it took for all redirection
                             steps include name lookup,  connect,  pretransfer
                             and  transfer  before  the  final transaction was
                             started. time_redirect shows the complete  execu‐
                             tion  time  for  multiple redirections. (Added in
                             7.12.3)

              time_starttransfer
                             The time, in seconds,  it  took  from  the  start
                             until  the first byte was just about to be trans‐
                             ferred. This includes time_pretransfer  and  also
                             the  time  the  server  needed  to  calculate the
                             result.

              time_total     The total time, in seconds, that the full  opera‐
                             tion lasted. The time will be displayed with mil‐
                             lisecond resolution.

              url_effective  The URL that was fetched last. This is most mean‐
                             ingful  if  you've  told curl to follow location:
                             headers.

       If this option is used several times, the last one will be used.

       -x, --proxy <[protocol://][user:password@]proxyhost[:port]>
              Use the specified HTTP proxy. If the port number is  not  speci‐
              fied, it is assumed at port 1080.

              This  option  overrides  existing environment variables that set
              the proxy to use. If there's an environment variable  setting  a
              proxy, you can set proxy to "" to override it.

              All operations that are performed over an HTTP proxy will trans‐
              parently be converted to HTTP. It means  that  certain  protocol
              specific operations might not be available. This is not the case
              if you can tunnel through the proxy, as one with the -p, --prox‐
              ytunnel option.

              User and password that might be provided in the proxy string are
              URL decoded by curl. This allows you to pass in special  charac‐
              ters such as @ by using %40 or pass in a colon with %3a.

              The  proxy host can be specified the exact same way as the proxy
              environment variables, including the protocol  prefix  (http://)
              and the embedded user + password.

              From  7.21.7,  the  proxy  string may be specified with a proto‐
              col://  prefix  to  specify  alternative  proxy  protocols.  Use
              socks4://,  socks4a://,  socks5://  or socks5h:// to request the
              specific SOCKS  version  to  be  used.  No  protocol  specified,
              http:// and all others will be treated as HTTP proxies.

              If this option is used several times, the last one will be used.

       -X, --request <command>
              (HTTP) Specifies a custom request method to use when communicat‐
              ing with the HTTP server.  The specified request  will  be  used
              instead  of  the  method otherwise used (which defaults to GET).
              Read the HTTP 1.1 specification for  details  and  explanations.
              Common  additional  HTTP  requests  include  PUT and DELETE, but
              related technologies like WebDAV offers PROPFIND, COPY, MOVE and
              more.

              Normally  you  don't  need  this option. All sorts of GET, HEAD,
              POST and PUT requests are rather invoked by using dedicated com‐
              mand line options.

              This  option  only  changes  the  actual  word  used in the HTTP
              request, it does not alter the way curl behaves. So for  example
              if  you  want  to make a proper HEAD request, using -X HEAD will
              not suffice. You need to use the -I, --head option.

              (FTP) Specifies a custom FTP command to use instead of LIST when
              doing file lists with FTP.

              If this option is used several times, the last one will be used.


       --xattr
              When  saving  output  to a file, this option tells curl to store
              certain file metadata in extened file attributes. Currently, the
              URL is stored in the xdg.origin.url attribute and, for HTTP, the
              content type is stored in the mime_type attribute. If  the  file
              system  does  not  support  extended  attributes,  a  warning is
              issued.


       -y, --speed-time <time>
              If a download is slower than speed-limit bytes per second during
              a speed-time period, the download gets aborted. If speed-time is
              used, the default speed-limit will be 1 unless set with -Y.

              This option controls transfers and thus  will  not  affect  slow
              connects  etc.  If this is a concern for you, try the --connect-
              timeout option.

              If this option is used several times, the last one will be used.

       -Y, --speed-limit <speed>
              If a download is slower than this given speed (in bytes per sec‐
              ond)  for  speed-time seconds it gets aborted. speed-time is set
              with -y and is 30 if not set.

              If this option is used several times, the last one will be used.

       -z, --time-cond <date expression>|<file>
              (HTTP/FTP) Request a file that has been modified later than  the
              given  time  and date, or one that has been modified before that
              time. The <date expression> can be all sorts of date strings  or
              if it doesn't match any internal ones, it is taken as a filename
              and tries to get  the  modification  date  (mtime)  from  <file>
              instead.  See  the curl_getdate(3) man pages for date expression
              details.

              Start the date expression with a dash (-) to make it request for
              a  document that is older than the given date/time, default is a
              document that is newer than the specified date/time.

              If this option is used several times, the last one will be used.

       -h, --help
              Usage help.

       -M, --manual
              Manual. Display the huge help text.

       -V, --version
              Displays information about curl and the libcurl version it uses.

              The first line includes the full version of  curl,  libcurl  and
              other 3rd party libraries linked with the executable.

              The  second  line (starts with "Protocols:") shows all protocols
              that libcurl reports to support.

              The third line (starts with "Features:") shows specific features
              libcurl reports to offer. Available features include:

              IPv6   You can use IPv6 with this.

              krb4   Krb4 for FTP is supported.

              SSL    HTTPS and FTPS are supported.

              libz   Automatic  decompression of compressed files over HTTP is
                     supported.

              NTLM   NTLM authentication is supported.

              GSS-Negotiate
                     Negotiate authentication and krb5 for FTP is supported.

              Debug  This curl uses a libcurl built with Debug.  This  enables
                     more  error-tracking  and memory debugging etc. For curl-
                     developers only!

              AsynchDNS
                     This curl uses asynchronous name resolves.

              SPNEGO SPNEGO Negotiate authentication is supported.

              Largefile
                     This curl supports transfers of large files, files larger
                     than 2GB.

              IDN    This curl supports IDN - international domain names.

              SSPI   SSPI  is  supported. If you use NTLM and set a blank user
                     name, curl will authenticate with your current  user  and
                     password.

              TLS-SRP
                     SRP  (Secure Remote Password) authentication is supported
                     for TLS.

              Metalink
                     This curl supports Metalink (both version 3  and  4  (RFC
                     5854)),  which  describes  mirrors and hashes.  curl will
                     use mirrors for failover if there are errors (such as the
                     file or server not being available).

FILES
       ~/.curlrc
              Default config file, see -K, --config for details.

ENVIRONMENT
       The environment variables can be specified in lower case or upper case.
       The lower case version has precedence. http_proxy is an exception as it
       is only available in lower case.

       Using  an  environment variable to set the proxy has the same effect as
       using the --proxy option.


       http_proxy [protocol://]<host>[:port]
              Sets the proxy server to use for HTTP.

       HTTPS_PROXY [protocol://]<host>[:port]
              Sets the proxy server to use for HTTPS.

       [url-protocol]_PROXY [protocol://]<host>[:port]
              Sets the proxy server to use for [url-protocol], where the  pro‐
              tocol  is  a  protocol  that curl supports and as specified in a
              URL. FTP, FTPS, POP3, IMAP, SMTP, LDAP etc.

       ALL_PROXY [protocol://]<host>[:port]
              Sets the proxy server to use if no  protocol-specific  proxy  is
              set.

       NO_PROXY <comma-separated list of hosts>
              list  of  host names that shouldn't go through any proxy. If set
              to a asterisk '*' only, it matches all hosts.

PROXY PROTOCOL PREFIXES
       Since curl version 7.21.7, the proxy string may  be  specified  with  a
       protocol:// prefix to specify alternative proxy protocols.

       If  no  protocol  is  specified  in  the  proxy string or if the string
       doesn't match a supported one, the proxy will be  treated  as  an  HTTP
       proxy.

       The supported proxy protocol prefixes are as follows:

       socks4://
              Makes it the equivalent of --socks4

       socks4a://
              Makes it the equivalent of --socks4a

       socks5://
              Makes it the equivalent of --socks5

       socks5h://
              Makes it the equivalent of --socks5-hostname

EXIT CODES
       There  are  a  bunch  of  different error codes and their corresponding
       error messages that may appear during bad conditions. At  the  time  of
       this writing, the exit codes are:

       1      Unsupported protocol. This build of curl has no support for this
              protocol.

       2      Failed to initialize.

       3      URL malformed. The syntax was not correct.

       4      A feature or option that  was  needed  to  perform  the  desired
              request  was  not  enabled  or was explicitly disabled at build-
              time. To make curl able to do this, you  probably  need  another
              build of libcurl!

       5      Couldn't  resolve  proxy.  The  given  proxy  host  could not be
              resolved.

       6      Couldn't resolve host. The given remote host was not resolved.

       7      Failed to connect to host.

       8      FTP weird server reply.  The  server  sent  data  curl  couldn't
              parse.

       9      FTP  access  denied. The server denied login or denied access to
              the particular resource or directory you wanted to  reach.  Most
              often  you  tried to change to a directory that doesn't exist on
              the server.

       11     FTP weird PASS reply. Curl couldn't parse the reply sent to  the
              PASS request.

       13     FTP  weird PASV reply, Curl couldn't parse the reply sent to the
              PASV request.

       14     FTP weird 227 format.  Curl  couldn't  parse  the  227-line  the
              server sent.

       15     FTP  can't  get host. Couldn't resolve the host IP we got in the
              227-line.

       17     FTP couldn't set binary.  Couldn't  change  transfer  method  to
              binary.

       18     Partial file. Only a part of the file was transferred.

       19     FTP  couldn't download/access the given file, the RETR (or simi‐
              lar) command failed.

       21     FTP quote error. A quote command returned error from the server.

       22     HTTP page not retrieved. The requested  url  was  not  found  or
              returned  another  error  with  the HTTP error code being 400 or
              above. This return code only appears if -f, --fail is used.

       23     Write error. Curl couldn't write data to a local  filesystem  or
              similar.

       25     FTP  couldn't  STOR  file. The server denied the STOR operation,
              used for FTP uploading.

       26     Read error. Various reading problems.

       27     Out of memory. A memory allocation request failed.

       28     Operation timeout. The specified  time-out  period  was  reached
              according to the conditions.

       30     FTP  PORT  failed.  The PORT command failed. Not all FTP servers
              support the PORT  command,  try  doing  a  transfer  using  PASV
              instead!

       31     FTP  couldn't use REST. The REST command failed. This command is
              used for resumed FTP transfers.

       33     HTTP range error. The range "command" didn't work.

       34     HTTP post error. Internal post-request generation error.

       35     SSL connect error. The SSL handshaking failed.

       36     FTP bad download resume. Couldn't continue  an  earlier  aborted
              download.

       37     FILE couldn't read file. Failed to open the file. Permissions?

       38     LDAP cannot bind. LDAP bind operation failed.

       39     LDAP search failed.

       41     Function not found. A required LDAP function was not found.

       42     Aborted by callback. An application told curl to abort the oper‐
              ation.

       43     Internal error. A function was called with a bad parameter.

       45     Interface error. A specified outgoing  interface  could  not  be
              used.

       47     Too many redirects. When following redirects, curl hit the maxi‐
              mum amount.

       48     Unknown option specified to libcurl.  This  indicates  that  you
              passed  a weird option to curl that was passed on to libcurl and
              rejected. Read up in the manual!

       49     Malformed telnet option.

       51     The peer's SSL certificate or SSH MD5 fingerprint was not OK.

       52     The server didn't reply anything, which here  is  considered  an
              error.

       53     SSL crypto engine not found.

       54     Cannot set SSL crypto engine as default.

       55     Failed sending network data.

       56     Failure in receiving network data.

       58     Problem with the local certificate.

       59     Couldn't use specified SSL cipher.

       60     Peer  certificate cannot be authenticated with known CA certifi‐
              cates.

       61     Unrecognized transfer encoding.

       62     Invalid LDAP URL.

       63     Maximum file size exceeded.

       64     Requested FTP SSL level failed.

       65     Sending the data requires a rewind that failed.

       66     Failed to initialise SSL Engine.

       67     The user name, password, or similar was not  accepted  and  curl
              failed to log in.

       68     File not found on TFTP server.

       69     Permission problem on TFTP server.

       70     Out of disk space on TFTP server.

       71     Illegal TFTP operation.

       72     Unknown TFTP transfer ID.

       73     File already exists (TFTP).

       74     No such user (TFTP).

       75     Character conversion failed.

       76     Character conversion functions required.

       77     Problem with reading the SSL CA cert (path? access rights?).

       78     The resource referenced in the URL does not exist.

       79     An unspecified error occurred during the SSH session.

       80     Failed to shut down the SSL connection.

       82     Could  not  load  CRL  file,  missing  or wrong format (added in
              7.19.0).

       83     Issuer check failed (added in 7.19.0).

       84     The FTP PRET command failed

       85     RTSP: mismatch of CSeq numbers

       86     RTSP: mismatch of Session Identifiers

       87     unable to parse FTP file list

       88     FTP chunk callback reported error

       XX     More error codes will appear here in future releases. The exist‐
              ing ones are meant to never change.

AUTHORS / CONTRIBUTORS
       Daniel  Stenberg is the main author, but the whole list of contributors
       is found in the separate THANKS file.

WWW
       http://curl.haxx.se

FTP
       ftp://ftp.sunet.se/pub/www/utilities/curl/

SEE ALSO
       ftp(1), wget(1)



Curl 7.27.0                      27 July 2012                          curl(1)

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