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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 interaction.

       curl offers a busload of useful	tricks	like  proxy  support,  user  authentication,  FTP
       upload,	HTTP  post,  SSL connections, cookies, file transfer resume 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 description 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  sequen-
       tial 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 example, 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 connects / 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 trans-
       ferred 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  opera-
       tion and it is about to write data to the terminal, it disables the progress meter as oth-
       erwise 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-". How-
       ever, in this list we mostly only list and show the --option version of them.  (This  con-
       cept 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.)

       -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 set more than once, the last one will be the one that's 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 supposedly the data pre-
	      viously 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 filename 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 set more than once, the last one will be the one that's used.

       -B/--use-ascii
	      Enable ASCII transfer when using FTP or LDAP. 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).

       --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://directory.fedora.red-
	      hat.com/docs/mod_nss.html#Directives

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

       --compressed
	      (HTTP)  Request a compressed response using one of the algorithms libcurl 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.

       -c/--cookie-jar <file name>
	      Specify  to  which file you want curl to write all cookies after a completed opera-
	      tion. 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
	      written. 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.

	      NOTE  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 feedback 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.

       --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 sub-
	      mit  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 command 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 @foobar.

       --data-binary <data>
	      (HTTP) This posts data exactly as specified with no extra processing 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 separa-
	      tor 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.

       --digest
	      (HTTP) Enables HTTP Digest authentication. This is a authentication  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, the following occurrences make no difference.

       --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 extensions 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.

	      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 EPRT again and --no-epsv is an alias for
	      --disable-epsv.

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

       -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 a HTTP site
	      sends to you. Cookies from the headers could then be read in a second curl  invoca-
	      tion  by using the -b/--cookie option! The -c/--cookie-jar option is however a bet-
	      ter 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.

       -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 follows 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.

       --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 useful 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.

       -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 protocol. The certificate must be in PEM for-
	      mat.  If the optional password isn't specified, it will be queried for on the  ter-
	      minal.  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  environ-
	      ment variable SSL_DIR (or by default /etc/pki/nssdb). If the NSS PEM PKCS#11 module
	      (libnsspem.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 this option is used several times, the last one will be used.

       --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 vari-
	      able.

	      The windows version of curl will automatically look  for	a  CA  certs  file  named
	      'curl-ca-bundle.crt',  either  in the same directory 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 then this option tells curl the  nick-
	      name  of	the CA certificate to use within the NSS database defined by the environ-
	      ment variable SSL_DIR (or by default /etc/pki/nssdb).  If the NSS PEM PKCS#11  mod-
	      ule (libnsspem.so) is available then PEM files may be loaded.

	      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. 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 certifi-
	      cates.

	      If this option 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
	      a HTTP server fails to deliver a document, it returns an HTML document  stating  so
	      (which  often  also  describes why and more). This flag will prevent curl from out-
	      putting 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).

       --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 twice, the second will override the previous use.

       --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 a FTP(S) server. The
	      method argument should be one of the following 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 commands. 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, the following occurrences make no difference.
	      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-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-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)

       --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-con-
	      trol and --ssl-reqd for different levels of encryption required. (Added in 7.20.0)

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

       --ftp-ssl-control
	      (FTP) Require SSL/TLS for the FTP login, clear for transfer.  Allows secure authen-
	      tication, but non-encrypted data transfers for efficiency.  Fails the  transfer  if
	      the server doesn't support SSL/TLS.  (Added in 7.16.0)

       --ssl-reqd
	      (FTP, POP3, IMAP, SMTP) Require SSL/TLS for the connection.  Terminates the connec-
	      tion 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)  and	that  can
	      still be used but will be removed in a future version.

       --ftp-ssl-ccc
	      (FTP)  Use CCC (Clear Command Channel) Shuts down the SSL/TLS layer after authenti-
	      cating. The rest of the control channel communication  will  be  unencrypted.  This
	      allows  NAT routers to follow 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)

       -F/--form <name=content>
	      (HTTP) This lets curl emulate a filled-in form in which a user has pressed the sub-
	      mit 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 differ-
	      ence 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 'password' 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 filename. This goes for
	      both @ and < constructs.

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

	      See further examples and details in the MANUAL.

	      This option can be used multiple times.

       --form-string <name=string>
	      (HTTP) Similar to --form except that the value string for the  named  parameter  is
	      used  literally.	Leading  '@'  and  '<' characters, and the ';type=' string in the
	      value have no special meaning. Use this in preference to --form if there's any pos-
	      sibility	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 inter-
	      preted 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 a 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, the following occurrences make no difference.
	      This  is	because  undoing  a  GET  doesn't make sense, but you should then instead
	      enforce the alternative method you prefer.

       -h/--help
	      Usage help.

       -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 trickier 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:".

	      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>
	      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. This option is only for SCP and SFTP  transfers.
	      (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 incorrect  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...

       --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.

       -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 a FTP  or
	      FILE file, curl displays the file size and last modification time only.

       -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 cer-
	      tificate	bundle installed by default. This makes all connections considered "inse-
	      cure" fail unless -k/--insecure is used.

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

       --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 multiple times, the last occurrence sets the amount.

       --key <key>
	      (SSL/SSH)  Private  key  file  name. Allows you to provide your private key in this
	      separate file.

	      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 provided 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) sup-
	      port. This is not very common. Use -V/--version to see if your curl supports it.

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

       -K/--config <config file>
	      Specify which config file to read curl arguments from. The config 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
	      specified  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 comment. 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 sys-
	      tems (which returns the home dir given the current user in your  system).  On  Win-
	      dows,  it  then checks for the APPDATA variable, or as a last resort the '%USERPRO-
	      FILE%\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.

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

	      NOTE: this does not properly support -F and the sending of multipart formposts,  so
	      in  those  cases	the  output  program will be missing necessary calls to curl_for-
	      madd(3), and possibly more.

	      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  band-
	      width.

	      The  given speed is measured in bytes/second, unless a suffix is appended.  Append-
	      ing 'k' or 'K' will count the number as kilobytes, '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.

       -l/--list-only
	      (FTP)  When  listing  an FTP directory, this switch forces a name-only view.  Espe-
	      cially 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.

       --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)

       -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 --location-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.

       --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).

       --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)

       --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 transfer ends up being larger than this given
	      limit. This concerns both FTP and HTTP transfers.

       -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 hanging 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.

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

       -n/--netrc
	      Makes curl scan the .netrc (_netrc on Windows) file in the  user's  home	directory
	      for  login  name and password. This is typically 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 permis-
	      sions (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

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

       --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.

       --negotiate
	      (HTTP) Enables GSS-Negotiate authentication. The GSS-Negotiate method was  designed
	      by Microsoft and is used in their web applications. It is primarily meant as a sup-
	      port 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, the following occurrences make no difference.

       -N/--no-buffer
	      Disables	the  buffering of the output stream. In normal work situations, 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.

       --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 con-
	      tains 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 people 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 authentication 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, the following occurrences make no difference.

       -o/--output <file>
	      Write output to <file> instead of stdout. If you are using {} or [] to fetch multi-
	      ple  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 directories 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.

       --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  spe-
	      cific  URL  after  --remote-name-all  has  been  used, you must use "-o -" or --no-
	      remote-name. (Added in 7.19.0)

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

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

       --post301
	      Tells curl to respect RFC 2616/10.3.2  and  not  convert	POST  requests	into  GET
	      requests	when  following a 301 redirection. The non-RFC behaviour is ubiquitous in
	      web browsers, so curl does the conversion by default to maintain consistency.  How-
	      ever,  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
	      Tells curl to respect RFC 2616/10.3.2  and  not  convert	POST  requests	into  GET
	      requests	when  following a 302 redirection. The non-RFC behaviour is ubiquitous in
	      web browsers, so curl does the conversion by default to maintain consistency.  How-
	      ever,  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)

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

	      +  Permit this protocol in addition to protocols already	permitted  (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 permitted), 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 protocols, 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 proto-
	      cols are represented.

	      (Added in 7.20.2)

       --proxy-anyauth
	      Tells curl to pick a suitable authentication method  when  communicating	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 communicating 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.

       -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	tunnel	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.

       --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.

       -P/--ftp-port <address>
	      (FTP) Reverses the default initiator/listener roles when connecting with FTP.  This
	      switch  makes curl use active mode. In practice, curl then tells the server to con-
	      nect 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 con-
		     nection

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

       -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 com-
	      mands 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 libcurl  has
	      changed the working directory, just before the transfer command(s), prefix the com-
	      mand with a '+' (this is only supported for FTP). You may  specify  any  number  of
	      commands.  If the server returns failure for one of the commands, the entire opera-
	      tion will be aborted. You must send syntactically correct FTP commands as  RFC  959
	      defines  to FTP servers, or one of the commands listed below to SFTP servers.  This
	      option can be used multiple times.

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

	      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 operand. 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  loca-
		     tion pointing to the source_file location.

	      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 current working direc-
		     tory.

	      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 operand.

	      rmdir directory
		     The rmdir command removes the directory entry specified by the directory op-
		     erand, provided it is empty.

	      symlink source_file target_file
		     See ln.

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

       -r/--range <range>
	      (HTTP/FTP/SFTP/FILE) Retrieve  a	byte  range  (i.e  a  partial  document)  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' syntax (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.

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

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

       --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 nor-
	      mally 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 multiple times, the last occurrence decide the amount.

       --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 multiple times, the last occurrence determines the amount.

       --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 per-
	      forming, 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 multiple times, the last occurrence determines the amount.

       -s/--silent
	      Silent or quiet mode. Don't show progress meter  or  error  messages.   Makes  Curl
	      mute.

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

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

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

	      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 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  exclu-
	      sive.

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

       --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  exclu-
	      sive.

	      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 exclu-
	      sive.

	      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 negotiated. 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 protec-
	      tion 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. This option has no point when you're
	      using a shell with decent redirecting capabilities.

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

       --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)

       -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.

       --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".  (Added in 7.21.4)

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

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

       -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 a
	      HTTP(S) server, the PUT command will be used.

	      Use the file name "-" (a single dash) to use stdin instead of a given file.  Alter-
	      nately,  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 speci-
	      fies what to upload and to where. curl also supports "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/

       --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)

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

	      (Added in 7.21.6)

       -u/--user <user:password>
	      Specify the user name and password to  use  for  server  authentication.	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 authentication,  you  can  force
	      curl to pick up the user name and password from your environment by simply specify-
	      ing 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 authentication.

	      If you use an SSPI-enabled curl binary and do NTLM authentication,  you  can  force
	      curl to pick up the user name and password from your environment by simply specify-
	      ing 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.

       -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.

       -w/--write-out <format>
	      Defines what to display on stdout after a completed and successful  operation.  The
	      format  is a string that may contain plain text mixed with any number of variables.
	      The string can be specified as "string", to get read from  a  particular	file  you
	      specify  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 %{vari-
	      able_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 occur-
	      rences of % must be doubled when using this option.

	      The variables available at this point are:

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

	      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)

	      time_total     The total time, in seconds, that the full operation lasted. The time
			     will be displayed with millisecond resolution.

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

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

	      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_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
			     negotiations   that  are  specific  to  the  particular  protocol(s)
			     involved.

	      time_redirect  The time, in seconds, it took for all redirection steps include name
			     lookup,  connect, pretransfer and transfer before the final transac-
			     tion was started. time_redirect shows the	complete  execution  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 transferred. This includes time_pretransfer and
			     also the time the server needed to calculate the result.

	      size_download  The total amount of bytes that were downloaded.

	      size_upload    The total amount of bytes that were uploaded.

	      size_header    The total amount of bytes of the downloaded headers.

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

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

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

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

	      num_connects   Number  of  new  connects	made  in  the  recent transfer. (Added in
			     7.12.3)

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

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

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

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

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

       -x/--proxy <proxyhost[:port]>
	      Use the specified HTTP proxy. If the port number is not specified, 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  over-
	      ride it.

	      Note that all operations that are performed over a HTTP proxy will transparently 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 done with
	      the -p/--proxytunnel option.

	      Starting with 7.14.1, the proxy host can be specified the exact  same  way  as  the
	      proxy environment variables, including the protocol prefix (http://) and the embed-
	      ded user + password.

	      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 communicating  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  explana-
	      tions.  Common  additional  HTTP requests include PUT and DELETE, but related tech-
	      nologies like WebDAV offers PROPFIND, COPY, MOVE and more.

	      (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.

       -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 second) 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>
	      (HTTP/FTP/FILE) 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 tries to get
	      the time from a given file name 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 speci-
	      fied date/time.

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

       --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
	      limitless.

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

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

       -1/--tlsv1
	      (SSL) Forces curl to use TLS version 1 when negotiating with a remote TLS server.

       -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  libcurl is capable of resolving an address to multiple IP versions (which it is
	      if it is IPv6-capable),  this  option  tells  libcurl  to  resolve  names  to  IPv4
	      addresses only.

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

       -#/--progress-bar
	      Make  curl  display  progress  information as a progress bar instead of the default
	      statistics.

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.

       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.

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

       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.

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  proba-
	      bly 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 similar) 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 upload-
	      ing.

       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  con-
	      ditions.

       30     FTP PORT failed. The PORT command failed. Not all FTP servers support the PORT com-
	      mand, 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 operation.

       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 maximum 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 certificates.

       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 existing 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 7.21.6				  14 April 2009 				  curl(1)
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