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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, SMB, SMBS,
       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 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.example.com/file[1-100].txt

	 ftp://ftp.example.com/file[001-100].txt    (with leading zeros)

	 ftp://ftp.example.com/file[a-z].txt

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

	 http://example.com/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://example.com/file[1-100:10].txt

	 http://example.com/file[a-z:2].txt

       When using [] or {} sequences when invoked from a command line  prompt,
       you probably have to put the full URL within double quotes to avoid the
       shell from interfering with it. This also  goes	for  other  characters
       treated special, like for example '&', '?' and '*'.

       Provide	the IPv6 zone index in the URL with an escaped percentage sign
       and the interface name. Like in

	 http://[fe80::3%25eth0]/

       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. The progress meter displays number of bytes and  the	speeds
       are  in	bytes per second. The suffixes (k, M, G, T, P) are 1024 based.
       For example 1k is 1024 bytes. 1M is 1048576 bytes.

       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,
       --output 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,  -#,
       --progress-bar  is your friend. You can also disable the progress meter
       completely with the -s, --silent option.

OPTIONS
       Options start with one or two dashes. Many of the  options  require  an
       additional value next to them.

       The  short  "single-dash"  form	of the options, -d for example, may be
       used with or without a space between it and its value, although a space
       is a recommended separator. The long "double-dash" form, -d, --data for
       example, requires a space between it and its value.

       Short version options that don't need any additional values can be used
       immediately  next  to  each other, like for example you can specify all
       the options -O, -L and -v at once as -OLv.

       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.)

       --abstract-unix-socket <path>
	      (HTTP)  Connect  through an abstract Unix domain socket, instead
	      of using the network.   Note:  netstat  shows  the  path	of  an
	      abstract	socket	prefixed with '@', however the <path> argument
	      should not have this leading character.

	      Added in 7.53.0.

       --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.

	      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.

	      Used together with -u, --user.

	      See also --proxy-anyauth and --basic and --digest.

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

       --basic
	      (HTTP) Tells curl to use	HTTP  Basic  authentication  with  the
	      remote  host.  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 --negotiate).

	      Used together with -u, --user.

	      See also --proxy-basic.

       --cacert <CA certificate>
	      (TLS) 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.

	      (iOS  and macOS only) If curl is built against Secure Transport,
	      then this option is supported for	 backward  compatibility  with
	      other  SSL  engines,  but it should not be set. If the option is
	      not set, then curl will use the certificates in the  system  and
	      user  Keychain to verify the peer, which is the preferred method
	      of verifying the peer's certificate chain.

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

       --capath <dir>
	      (TLS) 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.

       --cert-status
	      (TLS) Tells curl to verify the status of the server  certificate
	      by using the Certificate Status Request (aka. OCSP stapling) TLS
	      extension.

	      If this option is enabled and the server sends an invalid	 (e.g.
	      expired) response, if the response suggests that the server cer-
	      tificate has been revoked, or no response at  all	 is  received,
	      the verification fails.

	      This  is	currently  only implemented in the OpenSSL, GnuTLS and
	      NSS backends.

	      Added in 7.41.0.

       --cert-type <type>
	      (TLS) 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.

	      See also -E, --cert and --key and --key-type.

       -E, --cert <certificate[:password]>
	      (TLS) 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 PKCS#12 format if	 using	Secure
	      Transport,  or  PEM  format  if  using any other engine.	If the
	      optional password isn't specified, it will be queried for on the
	      terminal.	 Note  that  this  option assumes a "certificate" file
	      that is the private key and the client certificate concatenated!
	      See -E, --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.

	      (iOS  and macOS only) If curl is built against Secure Transport,
	      then the certificate string can either be the name of a certifi-
	      cate/private  key in the system or user keychain, or the path to
	      a PKCS#12-encoded certificate and private key. 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.

	      See also --cert-type and --key and --key-type.

       --ciphers <list of ciphers>
	      (TLS) 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:

	       https://curl.haxx.se/docs/ssl-ciphers.html

	      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.

       -K, --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 specified on the same  con-
	      fig  file	 line,	separated  by whitespace, colon, or the equals
	      sign. Long option names can optionally be given  in  the	config
	      file  without  the initial double dashes and if so, the colon or
	      equals characters can be used as separators. If  the  option  is
	      specified	 with  one  or	two  dashes,  there can be no colon or
	      equals character between the option and its parameter.

	      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 = "https://curl.haxx.se/docs/"

	      When curl is invoked, it always (unless -q, --disable  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 = "example.com"
	      output = "curlhere.html"
	      user-agent = "superagent/1.0"

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

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

       --connect-timeout <seconds>
	      Maximum time in seconds that  you	 allow	curl's	connection  to
	      take.   This  only  limits the connection phase, so if curl con-
	      nects within the given period it will continue - if not it  will
	      exit.  Since version 7.32.0, this option accepts decimal values.

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

	      See also -m, --max-time.

       --connect-to <HOST1:PORT1:HOST2:PORT2>

	      For  a  request to the given HOST:PORT pair, connect to CONNECT-
	      TO-HOST:CONNECT-TO-PORT instead.	This  option  is  suitable  to
	      direct requests at a specific server, e.g. at a specific cluster
	      node in a cluster of servers.   This  option  is	only  used  to
	      establish	 the  network connection. It does NOT affect the host-
	      name/port that is used for TLS/SSL (e.g. SNI, certificate	 veri-
	      fication)	 or  for the application protocols.  "host" and "port"
	      may be the empty string, meaning "any host/port".	  "connect-to-
	      host"  and "connect-to-port" may also be the empty string, mean-
	      ing "use the request's original host/port".

	      This option can be used many times to add many connect rules.

	      See also --resolve and -H, --header. Added in 7.49.0.

       -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.

	      See also -r, --range.

       -c, --cookie-jar <filename>
	      (HTTP) Specify to which file you want curl to write all  cookies
	      after  a	completed  operation. Curl writes all cookies from its
	      in-memory cookie storage to the given file at the end of	opera-
	      tions.  If  no  cookies  are known, no data 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.

	      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,
	      --verbose 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.

       -b, --cookie <data>
	      (HTTP) Pass the data to the HTTP server in the Cookie header. It
	      is  supposedly 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 argument, it is instead treated
	      as a filename to read previously stored cookie from. This option
	      also  activates  the  cookie  engine which will make curl record
	      incoming cookies, which may be handy if  you're  using  this  in
	      combination  with	 the  -L, --location option or do multiple URL
	      transfers on the same invoke.

	      The file format of the file to read cookies from should be plain
	      HTTP  headers  (Set-Cookie style) or the Netscape/Mozilla cookie
	      file format.

	      The file specified with -b, --cookie is only used as  input.  No
	      cookies  will  be written to the file. To store cookies, use the
	      -c, --cookie-jar option.

	      Exercise caution if you  are  using  this	 option	 and  multiple
	      transfers may occur.  If you use the NAME1=VALUE1; format, or in
	      a file use the Set-Cookie format and  don't  specify  a  domain,
	      then the cookie is sent for any domain (even after redirects are
	      followed) and cannot be modified by a server-set cookie. If  the
	      cookie  engine is enabled and a server sets a cookie of the same
	      name then both will be sent on a future transfer to that server,
	      likely  not  what	 you  intended.	 To address these issues set a
	      domain in Set-Cookie (doing that will include  sub  domains)  or
	      use the Netscape format.

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

	      Users very often want to both read cookies from a file and write
	      updated cookies back to a file, so using both -b,	 --cookie  and
	      -c, --cookie-jar in the same command line is common.

       --create-dirs
	      When used in conjunction with the -o, --output option, curl will
	      create the necessary local directory hierarchy as	 needed.  This
	      option  creates the dirs mentioned with the -o, --output option,
	      nothing else. If the --output 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 SMTP)  Convert  LF  to  CRLF	 in  upload.  Useful  for  MVS
	      (OS/390).

	      (SMTP added in 7.40.0)

       --crlfile <file>
	      (TLS) Provide a file using PEM format with a Certificate Revoca-
	      tion List that may specify peer certificates that are to be con-
	      sidered revoked.

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

	      Added in 7.19.7.

       --data-ascii <data>
	      (HTTP) This is just an alias for -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 -d, --data
	      does, except that newlines and carriage  returns	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-raw <data>
	      (HTTP) This posts data similarly to -d, --data but  without  the
	      special interpretation of the @ character.

	      See also -d, --data. Added in 7.43.0.

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

	      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.

       See also -d, --data and --data-raw. Added in 7.18.0.

       -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.

	      --data-raw is almost the same but does not have a special inter-
	      pretation	 of  the  @ character. 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. Multiple files can also be specified. Post-
	      ing data from a file named  from	a  file	 like  that,  carriage
	      returns and newlines will be stripped out. If you don't want the
	      @ character to have  a  special  interpretation  use  --data-raw
	      instead.

	      See also --data-binary and --data-urlencode and --data-raw. This
	      option overrides -F, --form and -I, --head and --upload.

       --delegation <LEVEL>
	      (GSS/kerberos) Set LEVEL to tell the server what it  is  allowed
	      to delegate when it comes to user credentials.

	      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.

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

	      See  also	 -u,  --user  and  --proxy-digest  and --anyauth. This
	      option overrides --basic and --ntlm and --negotiate.

       --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 accessed using IPv6, 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) (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.

       -q, --disable
	      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.

       --dns-interface <interface>
	      (DNS) Tell curl to send outgoing DNS  requests  through  <inter-
	      face>.  This  option is a counterpart to --interface (which does
	      not affect DNS). The supplied string must be an  interface  name
	      (not an address).

	      See  also	 --dns-ipv4-addr  and --dns-ipv6-addr. --dns-interface
	      requires that the underlying libcurl was	built  to  support  c-
	      ares. Added in 7.33.0.

       --dns-ipv4-addr <address>
	      (DNS)  Tell  curl	 to  bind to <ip-address> when making IPv4 DNS
	      requests, so that the DNS requests originate from this  address.
	      The argument should be a single IPv4 address.

	      See  also	 --dns-interface  and --dns-ipv6-addr. --dns-ipv4-addr
	      requires that the underlying libcurl was	built  to  support  c-
	      ares. Added in 7.33.0.

       --dns-ipv6-addr <address>
	      (DNS)  Tell  curl	 to  bind to <ip-address> when making IPv6 DNS
	      requests, so that the DNS requests originate from this  address.
	      The argument should be a single IPv6 address.

	      See  also	 --dns-interface  and --dns-ipv4-addr. --dns-ipv6-addr
	      requires that the underlying libcurl was	built  to  support  c-
	      ares. Added in 7.33.0.

       --dns-servers <addresses>
	      Set  the	list  of  DNS servers to be used instead of the system
	      default.	The list of IP addresses should be separated with com-
	      mas. Port numbers may also optionally be given as :<port-number>
	      after each IP address.

	      --dns-servers requires that the underlying libcurl was built  to
	      support c-ares. Added in 7.33.0.

       -D, --dump-header <filename>
	      (HTTP  FTP) Write the received 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 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.

	      See also -o, --output.

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

	      See also --random-file.

       --engine <name>
	      (TLS)  Select the OpenSSL crypto engine to use for cipher opera-
	      tions. 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
	      Sets a range of environment variables, using the names  the  -w,
	      --write-out  option supports, to allow easier extraction of use-
	      ful information after having run curl.

	      --environment requires that the underlying libcurl was built  to
	      support RISC OS.

       --expect100-timeout <seconds>
	      (HTTP) Maximum time in seconds that you allow curl to wait for a
	      100-continue response when curl emits an	Expects:  100-continue
	      header  in  its  request.	 By default curl will wait one second.
	      This option accepts decimal values! When curl stops waiting,  it
	      will continue as if the response has been received.

	      See also --connect-timeout. Added in 7.47.0.

       --fail-early
	      Fail and exit on first detected error.

	      When  curl is used to do multiple transfers on the command line,
	      it will attempt to operate on each given URL,  one  by  one.  By
	      default,	it will ignore errors if there are more URLs given and
	      the last URL's  success  will  determine	the  error  code  curl
	      returns.	So  early failures will be "hidden" by subsequent suc-
	      cessful transfers.

	      Using this option, curl will instead  return  an	error  on  the
	      first  transfers	that  fails, independent on the amount of more
	      URLs that are given on the command line. This way,  no  transfer
	      failures go undetected by scripts and similar.

	      This  option  will  apply for all given URLs even if you use -:,
	      --next.

	      Added in 7.52.0.

       -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).

       --false-start
	      (TLS)  Tells  curl  to use false start during the TLS handshake.
	      False start is a mode where a  TLS  client  will	start  sending
	      application data before verifying the server's Finished message,
	      thus saving a round trip when performing a full handshake.

	      This is currently only implemented in the NSS and Secure	Trans-
	      port (on iOS 7.0 or later, or OS X 10.9 or later) backends.

	      Added in 7.42.0.

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

	      See also -F, --form.

       -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  an image to a server, where 'profile' is the
	      name of the form-field to which portrait.jpg will be the input:

	       curl -F profile=@portrait.jpg https://example.com/upload.cgi

	      To read content from stdin instead of a file, use - as the file-
	      name.  This  goes	 for both @ and < constructs. Unfortunately it
	      does not support reading the file from a named pipe or  similar,
	      as it needs the full size before the transfer starts.

	      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" example.com

	      or

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

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

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

	      or

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

	      This option overrides -d, --data and -I, --head and --upload.

       --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.

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

	      Added in 7.13.0.

       --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.

	      See also --create-dirs.

       --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.

	      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.

	      See also --disable-epsv. Added in 7.11.0.

       -P, --ftp-port <address>
	      (FTP)  Reverses  the  default initiator/listener roles when con-
	      necting with FTP. This option makes curl use active  mode.  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++.

       Since  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.

       See also --ftp-pasv and --disable-eprt.

       --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 7.20.0.

       --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.

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

	      See also --ftp-pasv. Added in 7.14.2.

       --ftp-ssl-ccc-mode <active/passive>
	      (FTP) 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.

	      See also --ftp-ssl-ccc. Added in 7.16.2.

       --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 also --ssl and --ftp-ssl-ccc-mode. Added in 7.16.1.

       --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.

       -G, --get
	      When  used,  this	 option	 will make all data specified with -d,
	      --data, --data-binary or --data-urlencode 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,	--head,	 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.

       -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.

       -I, --head
	      (HTTP FTP FILE) Fetch the headers 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.

       -H, --header <header>
	      (HTTP) Extra header to include in the request when sending  HTTP
	      to  a  server. 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  per-
	      fectly well what you're doing. Remove an internal header by giv-
	      ing 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-Custom-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.

	      Starting in 7.37.0, you need --proxy-header to send custom head-
	      ers intended for a proxy.

	      Example:

	       curl -H "X-First-Name: Joe" http://example.com/

	      WARNING:	headers	 set  with  this  option  will	be  set in all
	      requests - even after redirects are  followed,  like  when  told
	      with  -L,	 --location. This can lead to the header being sent to
	      other hosts than the original host, so sensitive headers	should
	      be used with caution combined with following redirects.

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

       -h, --help
	      Usage help. This lists all current command line options  with  a
	      short description.

       --hostpubmd5 <md5>
	      (SFTP  SCP)  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.

       -0, --http1.0
	      (HTTP) Tells curl to use HTTP version 1.0 instead of  using  its
	      internally preferred HTTP version.

	      This option overrides --http1.1 and --http2.

       --http1.1
	      (HTTP) Tells curl to use HTTP version 1.1.

	      This  option  overrides  -0,  --http1.0  and  --http2.  Added in
	      7.33.0.

       --http2-prior-knowledge
	      (HTTP) Tells curl to  issue  its	non-TLS	 HTTP  requests	 using
	      HTTP/2  without  HTTP/1.1	 Upgrade.  It requires prior knowledge
	      that the server supports HTTP/2 straight	away.  HTTPS  requests
	      will  still  do HTTP/2 the standard way with negotiated protocol
	      version in the TLS handshake.

	      --http2-prior-knowledge requires that the underlying libcurl was
	      built to support HTTP/2. This option overrides --http1.1 and -0,
	      --http1.0 and --http2. Added in 7.49.0.

       --http2
	      (HTTP) Tells curl to use HTTP version 2.

	      See also --no-alpn. --http2 requires that the underlying libcurl
	      was built to support HTTP/2. This option overrides --http1.1 and
	      -0, --http1.0 and --http2-prior-knowledge. Added in 7.33.0.

       --ignore-content-length
	      (FTP HTTP) For 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	 giga-
	      bytes.

	      For  FTP (since 7.46.0), skip the RETR command to figure out the
	      size before downloading a file.

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

	      See also -v, --verbose.

       -k, --insecure
	      (TLS) 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:
	       https://curl.haxx.se/docs/sslcerts.html

       --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 https://www.example.com/

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

	      See also --dns-interface.

       -4, --ipv4
	      This option tells curl to resolve names to IPv4 addresses	 only,
	      and not for example try IPv6.

	      See  also	 --http1.1  and	 --http2.  This	 option	 overrides -6,
	      --ipv6.

       -6, --ipv6
	      This option tells curl to resolve names to IPv6 addresses	 only,
	      and not for example try IPv4.

	      See  also	 --http1.1  and	 --http2.  This	 option	 overrides -6,
	      --ipv6.

       -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.

	      See also -b, --cookie and -c, --cookie-jar.

       --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.

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

	      Added in 7.18.0.

       --key-type <type>
	      (TLS) 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.

       --key <key>
	      (TLS 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:

	      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.

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

	      --krb  requires that the underlying libcurl was built to support
	      Kerberos.

       --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 - for
	      both downloads and uploads. This feature is useful if you have a
	      limited pipe and you'd like your transfer not to use your entire
	      bandwidth. To make it slower than it otherwise would be.

	      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.

	      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  POP3)  (FTP)  When	listing	 an FTP directory, this switch
	      forces a name-only view. This is especially useful if  the  user
	      wants  to	 machine-parse	the contents of an FTP directory since
	      the normal directory view doesn't use a standard look or format.
	      When used like this, the option causes a NLST command to be sent
	      to the server instead of LIST.

	      Note: Some FTP servers list only	files  in  their  response  to
	      NLST; they do not include sub-directories and symbolic links.

	      (POP3)  When  retrieving a specific email from POP3, this switch
	      forces a LIST command to be performed instead of RETR.  This  is
	      particularly  useful if the user wants to see if a specific mes-
	      sage id exists on the server and what size it is.

	      Note: When combined with -X, --request, this option can be  used
	      to send an UIDL command instead, so the user may use the email's
	      unique identifier rather	than  it's  message  id	 to  make  the
	      request.

	      Added in 7.21.5.

       --local-port <num/range>
	      Set  a  preferred single number or range (FROM-TO) 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 set-
	      ting this range to something too narrow might cause  unnecessary
	      connection setup failures.

	      Added in 7.15.2.

       --location-trusted
	      (HTTP)  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).

	      See also -u, --user.

       -L, --location
	      (HTTP)  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.

	      You can tell curl to not change the non-GET  request  method  to
	      GET  after  a  30x  response  by using the dedicated options for
	      that: --post301, --post302 and --post303.

       --login-options <options>
	      (IMAP POP3 SMTP) Specify the login options to use during	server
	      authentication.

	      You  can	use  the  login	 options  to specify protocol specific
	      options that may be used during authentication. At present  only
	      IMAP,  POP3 and SMTP support login options. For more information
	      about the login options please see RFC 2384, RFC 5092  and  IETF
	      draft draft-earhart-url-smtp-00.txt

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

	      Added in 7.34.0.

       --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.

	      See also --mail-rcpt and --mail-from. Added in 7.25.0.

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

	      See also --mail-rcpt and --mail-auth. Added in 7.20.0.

       --mail-rcpt <address>
	      (SMTP) Specify a single address, user name or mailing list name.
	      Repeat this option several times to send to multiple recipients.

	      When  performing a mail transfer, the recipient should specify a
	      valid email address to send the mail to.

	      When performing an  address  verification	 (VRFY	command),  the
	      recipient	 should be specified as the user name or user name and
	      domain (as per Section 3.5 of RFC5321). (Added in 7.34.0)

	      When performing a mailing list expand (EXPN command), the recip-
	      ient  should  be	specified using the mailing list name, such as
	      "Friends" or "London-Office".  (Added in 7.34.0)

	      Added in 7.20.0.

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

       --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.

	      See also --limit-rate.

       --max-redirs <num>
	      (HTTP)  Set  maximum  number  of redirection-followings allowed.
	      When -L, --location is used, is used to prevent curl  from  fol-
	      lowing  redirections "in absurdum". By default, the limit is set
	      to 50 redirections. Set this option to -1 to make it unlimited.

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

       -m, --max-time <time>
	      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.	 Since
	      7.32.0, this option accepts decimal values, but the actual time-
	      out will decrease in accuracy as the specified timeout increases
	      in decimal precision.

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

	      See also --connect-timeout.

       --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 -i,  --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.


	      --metalink requires that the underlying  libcurl	was  built  to
	      support metalink. Added in 7.27.0.

       --negotiate
	      (HTTP) Enables Negotiate (SPNEGO) authentication.

	      This  option  requires a library built with GSS-API or SSPI sup-
	      port. Use -V, --version  to  see	if  your  curl	supports  GSS-
	      API/SSPI or SPNEGO.

	      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,
	      --user option aren't actually used.

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

	      See also --basic and --ntlm and --anyauth and --proxy-negotiate.

       --netrc-file <filemame>
	      This  option  is similar to -n, --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, the last one  will
	      be used.

	      It will abide by --netrc-optional if specified.

	      This option overrides -n, --netrc. Added in 7.21.5.

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

	      See also --netrc-file. This option overrides -n, --netrc.

       -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(5) 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-read-
	      able). 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

       -:, --next
	      Tells curl to use a separate operation for the following URL and
	      associated  options.  This  allows  you  to  send	 several   URL
	      requests,	 each  with  their  own specific options, for example,
	      such as different user names or custom requests for each.

	      -:, --next will reset all local options  and  only  global  ones
	      will  have  their values survive over to the operation following
	      the -:, --next instruction. Global options  include  -v,	--ver-
	      bose, --trace, --trace-ascii and --fail-early.

	      For  example,  you can do both a GET and a POST in a single com-
	      mand line:

	       curl www1.example.com --next -d postthis www2.example.com

	      Added in 7.36.0.

       --no-alpn
	      (HTTPS) Disable the ALPN	TLS  extension.	 ALPN  is  enabled  by
	      default  if  libcurl was built with an SSL library that supports
	      ALPN. ALPN is used by a libcurl that supports HTTP/2 to  negoti-
	      ate HTTP/2 support with the server during https sessions.

	      See  also	 --no-npn  and	--http2.  --no-alpn  requires that the
	      underlying libcurl was built to support TLS. Added in 7.36.0.

       -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.

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

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

       --no-npn
	      (HTTPS) Disable the NPN TLS extension. NPN is enabled by default
	      if libcurl was built with an SSL library that supports NPN.  NPN
	      is  used	by  a libcurl that supports HTTP/2 to negotiate HTTP/2
	      support with the server during https sessions.

	      See also --no-alpn  and  --http2.	 --no-npn  requires  that  the
	      underlying libcurl was built to support TLS. Added in 7.36.0.

       --no-sessionid
	      (TLS)  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.

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

	      Added in 7.16.0.

       --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.

	      Since 7.53.0, This option overrides  the	environment  variables
	      that  disable the proxy. If there's an environment variable dis-
	      abling a proxy, you can set noproxy list to "" to override it.

	      Added in 7.19.4.

       --ntlm-wb
	      (HTTP) Enables NTLM much in the style --ntlm does, but hand over
	      the  authentication  to the separate binary ntlmauth application
	      that is executed when needed.

	      See also --ntlm and --proxy-ntlm.

       --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.

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

	      See also	--proxy-ntlm.  --ntlm  requires	 that  the  underlying
	      libcurl  was built to support TLS. This option overrides --basic
	      and --negotiated and --digest and --anyauth.

       --oauth2-bearer
	      (IMAP POP3 SMTP) Specify the Bearer Token for OAUTH  2.0	server
	      authentication. The Bearer Token is used in conjunction with the
	      user name which can be specified as part of  the	--url  or  -u,
	      --user options.

	      The  Bearer  Token  and user name are formatted according to RFC
	      6750.

	      If this option is used several times, the last one will be 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}.example.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. For example, if you specify two URLs on the	 same  command
	      line, you can use it like this:

		curl -o aa example.com -o bb example.net

	      and  the	order  of  the -o options and the URLs doesn't matter,
	      just that the first -o is for the first URL and so  on,  so  the
	      above command line can also be written as

		curl example.com example.net -o aa -o bb

	      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.

	      See   also  -O,  --remote-name  and  --remote-name-all  and  -J,
	      --remote-header-name.

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

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

       --path-as-is
	      Tell curl to not handle sequences of /../ or /./	in  the	 given
	      URL  path.  Normally curl will squash or merge them according to
	      standards but with this option set you tell it not to do that.

	      Added in 7.42.0.

       --pinnedpubkey <hashes>
	      (TLS) Tells curl to  use	the  specified	public	key  file  (or
	      hashes)  to  verify the peer. This can be a path to a file which
	      contains a single public key in PEM or DER format, or any number
	      of base64 encoded sha256 hashes preceded by 'sha256//' and sepa-
	      rated by ';'

	      When negotiating a TLS or SSL connection,	 the  server  sends  a
	      certificate  indicating  its identity. A public key is extracted
	      from this certificate and if it does not exactly match the  pub-
	      lic  key provided to this option, curl will abort the connection
	      before sending or receiving any data.

	      PEM/DER support:
		7.39.0: OpenSSL, GnuTLS and GSKit
		7.43.0: NSS and wolfSSL/CyaSSL
		7.47.0: mbedtls
		7.49.0: PolarSSL sha256 support:
		7.44.0: OpenSSL, GnuTLS, NSS and wolfSSL/CyaSSL.
		7.47.0: mbedtls
		7.49.0: PolarSSL Other SSL backends not supported.

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

       --post301
	      (HTTP) Tells curl to respect RFC 7231/6.4.2 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. However, a
	      server may require a POST to remain a POST after	such  a	 redi-
	      rection.	This  option is meaningful only when using -L, --loca-
	      tion.

	      See also --post302 and --post303 and -L,	--location.  Added  in
	      7.17.1.

       --post302
	      (HTTP) Tells curl to respect RFC 7231/6.4.3 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.  However,  a
	      server  may  require  a POST to remain a POST after such a redi-
	      rection. This option is meaningful only when using  -L,  --loca-
	      tion.

	      See  also	 --post301  and --post303 and -L, --location. Added in
	      7.19.1.

       --post303
	      (HTTP) Tells curl to respect RFC 7231/6.4.4 and not convert POST
	      requests into GET requests when following a 303 redirection. 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	 redi-
	      rection.	This  option is meaningful only when using -L, --loca-
	      tion.

	      See also --post302 and --post301 and -L,	--location.  Added  in
	      7.26.0.

       --preproxy [protocol://]host[:port]
	      Use  the	specified  SOCKS proxy before connecting to an HTTP or
	      HTTPS -x, --proxy. In such a case curl  first  connects  to  the
	      SOCKS  proxy  and	 then  connects (through SOCKS) to the HTTP or
	      HTTPS proxy. Hence pre proxy.

	      The pre proxy string should be specified with a protocol:// pre-
	      fix  to  specify	alternative  proxy  protocols.	Use socks4://,
	      socks4a://, socks5:// or	socks5h://  to	request	 the  specific
	      SOCKS  version  to be used. No protocol specified will make curl
	      default to SOCKS4.

	      If the port number is not specified in the proxy string,	it  is
	      assumed to be 1080.

	      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.

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

	      Added in 7.52.0.

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

	      This progress bar draws a single line of '#'  characters	across
	      the screen and shows a percentage if the transfer size is known.
	      For transfers without a known size, it will instead  output  one
	      '#' character for every 1024 bytes transferred.

       --proto-default <protocol>
	      Tells curl to use protocol for any URL missing a scheme name.

	      Example:

	       curl --proto-default https ftp.mozilla.org

	      An  unknown  or  unsupported  protocol causes error CURLE_UNSUP-
	      PORTED_PROTOCOL (1).

	      This option does not change the default proxy protocol (http).

	      Without this option curl would make a guess based on  the	 host,
	      see --url for details.

	      Added in 7.45.0.

       --proto-redir <protocols>
	      Tells  curl to limit what protocols it may use on redirect. Pro-
	      tocols denied by --proto are not overridden by this option.  See
	      --proto for how protocols are represented.

	      Example, allow only HTTP and HTTPS on redirect:

	       curl --proto-redir -all,http,https http://example.com

	      By default curl will allow all protocols on redirect except sev-
	      eral disabled for security reasons: Since 7.19.4	FILE  and  SCP
	      are  disabled,  and since 7.40.0 SMB and SMBS are also disabled.
	      Specifying all  or  +all	enables	 all  protocols	 on  redirect,
	      including those disabled for security.

	      Added in 7.20.2.

       --proto <protocols>
	      Tells  curl  to limit what protocols it may use in the transfer.
	      Protocols are evaluated left to right, are comma separated,  and
	      are each a protocol name or

	      +	 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 protocols, without rely-
       ing  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.

       See also --proto-redir and --proto-default. Added in 7.20.2.

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

	      See also -x, --proxy and --proxy-basic and --proxy-digest. 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.

	      See also -x, --proxy and --proxy-anyauth and --proxy-digest.

       --proxy-cacert <file>
	      Same as --cacert but used in HTTPS proxy context.

	      See  also	 --proxy-capath	 and  --cacert	and  --capath  and -x,
	      --proxy. Added in 7.52.0.

       --proxy-capath <dir>
	      Same as --capath but used in HTTPS proxy context.

	      See also --proxy-cacert and -x, --proxy and --capath.  Added  in
	      7.52.0.

       --proxy-cert-type <type>
	      Same as --cert-type but used in HTTPS proxy context.

	      Added in 7.52.0.

       --proxy-cert <cert[:passwd]>
	      Same as -E, --cert but used in HTTPS proxy context.

	      Added in 7.52.0.

       --proxy-ciphers <list>
	      Same as --ciphers but used in HTTPS proxy context.

	      Added in 7.52.0.

       --proxy-crlfile <file>
	      Same as --crlfile but used in HTTPS proxy context.

	      Added in 7.52.0.

       --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.

	      See also -x, --proxy and --proxy-anyauth and --proxy-basic.

       --proxy-header <header>
	      (HTTP)  Extra header to include in the request when sending HTTP
	      to a proxy. You may specify any number of extra headers. This is
	      the  equivalent option to -H, --header but is for proxy communi-
	      cation only like in CONNECT requests when you  want  a  separate
	      header  sent  to	the proxy to what is sent to the actual remote
	      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.

	      Headers  specified  with	this  option  will  not be included in
	      requests that curl knows will not be sent to a proxy.

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

	      Added in 7.37.0.

       --proxy-insecure
	      Same as -k, --insecure but used in HTTPS proxy context.

	      Added in 7.52.0.

       --proxy-key-type <type>
	      Same as --key-type but used in HTTPS proxy context.

	      Added in 7.52.0.

       --proxy-key <key>
	      Same as --key but used in HTTPS proxy context.

       --proxy-negotiate
	      Tells  curl  to  use HTTP Negotiate (SPNEGO) authentication when
	      communicating with the given proxy. Use --negotiate for enabling
	      HTTP Negotiate (SPNEGO) with a remote host.

	      See also --proxy-anyauth and --proxy-basic. 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.

	      See also --proxy-negotiate and --proxy-anyauth.

       --proxy-pass <phrase>
	      Same as --pass but used in HTTPS proxy context.

	      Added in 7.52.0.

       --proxy-service-name <name>
	      This  option  allows  you	 to  change the service name for proxy
	      negotiation.

	      Added in 7.43.0.

       --proxy-ssl-allow-beast
	      Same as --ssl-allow-beast but used in HTTPS proxy context.

	      Added in 7.52.0.

       --proxy-tlsauthtype <type>
	      Same as --tlsauthtype but used in HTTPS proxy context.

	      Added in 7.52.0.

       --proxy-tlspassword <string>
	      Same as --tlspassword but used in HTTPS proxy context.

	      Added in 7.52.0.

       --proxy-tlsuser <name>
	      Same as --tlsuser but used in HTTPS proxy context.

	      Added in 7.52.0.

       --proxy-tlsv1
	      Same as -1, --tlsv1 but used in HTTPS proxy context.

	      Added in 7.52.0.

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

	      If  you  use  a  Windows	SSPI-enabled curl binary and do either
	      Negotiate or NTLM authentication	then  you  can	tell  curl  to
	      select the user name and password from your environment by spec-
	      ifying a single colon with this option: "-U :".

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

       -x, --proxy [protocol://]host[:port]
	      Use the specified proxy.

	      The proxy string can be specified with a protocol:// prefix.  No
	      protocol specified or http:// will be treated as HTTP proxy. Use
	      socks4://, socks4a://, socks5:// or socks5h:// to request a spe-
	      cific SOCKS version to be used.  (The protocol support was added
	      in curl 7.21.7)

	      HTTPS proxy support via https:// protocol prefix	was  added  in
	      7.52.0 for OpenSSL, GnuTLS and NSS.

	      Unrecognized  and	 unsupported  proxy  protocols	cause an error
	      since 7.52.0.  Prior versions may ignore the  protocol  and  use
	      http:// instead.

	      If  the  port number is not specified in the proxy string, it is
	      assumed to be 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.

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

       --proxy1.0 <host[: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 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.

	      See also -x, --proxy.

       --pubkey <key>
	      (SFTP SCP) Public key file name. Allows you to provide your pub-
	      lic 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, --quote
	      (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  operation	 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. When speaking to an FTP
	      server, prefix the command with an asterisk  (*)	to  make  curl
	      continue	even if the command 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.

       --random-file <file>
	      Specify the path name to file containing what will be considered
	      as  random  data. The data may be 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	 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(*)(HTTP)

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

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

	      Only  digit characters (0-9) are valid in the 'start' and 'stop'
	      fields of the 'start-stop' range syntax. If a non-digit  charac-
	      ter is given in the range, the server's response will be unspec-
	      ified, 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  (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.

       -e, --referer <URL>
	      (HTTP) Sends the "Referrer 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  -e,
	      --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 -e, --referer.

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

	      See also -A, --user-agent and -H, --header.

       -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.

	      If  the  server  specifies a file name and a file with that name
	      already exists in the current working directory it will  not  be
	      overwritten and an error will occur. If the server doesn't spec-
	      ify a file name then this option has no effect.

	      There's no attempt to decode %-sequences (yet) in	 the  provided
	      file name, so this option may provide you with rather unexpected
	      file names.

	      WARNING: Exercise judicious use of this  option,	especially  on
	      Windows.	A  rogue  server  could	 send you the name of a DLL or
	      other file that could possibly be loaded automatically  by  Win-
	      dows or some third party software.

       --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.

       -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 file will be saved in the current working directory. If  you
	      want  the	 file  saved  in  a different directory, make sure you
	      change the current working directory before invoking  curl  with
	      this option.

	      The  remote  file	 name  to use for saving is extracted from the
	      given URL, nothing else, and if it already  exists  it  will  be
	      overwritten.  If	you  want  the server to be able to choose the
	      file name refer to -J, --remote-header-name which can be used in
	      addition	to  this option. If the server chooses a file name and
	      that name already exists it will not be overwritten.

	      There is no URL decoding done on the file name. If it has %20 or
	      other  URL  encoded parts of the name, they will end up as-is as
	      file name.

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

       -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.

       -X, --request <command>
	      (HTTP) Specifies a custom request method to use when communicat-
	      ing with the HTTP server.	 The specified request method 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 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.

	      The method string you set with -X, --request will	 be  used  for
	      all  requests,  which  if you for example use -L, --location may
	      cause unintended side-effects when curl doesn't  change  request
	      method according to the HTTP 30x response codes - and similar.

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

	      (POP3) Specifies a custom POP3 command to use instead of LIST or
	      RETR. (Added in 7.26.0)

	      (IMAP)  Specifies	 a custom IMAP command to use instead of LIST.
	      (Added in 7.30.0)

	      (SMTP) Specifies a custom SMTP command to use instead of HELP or
	      VRFY. (Added in 7.34.0)

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

       --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.

	      The provided address set by this option will be used even if -4,
	      --ipv4 or -6, --ipv6 is set to make curl use another IP version.

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

	      Added in 7.21.3.

       --retry-connrefused
	      In addition to the other conditions, consider ECONNREFUSED as  a
	      transient	 error	too  for --retry. This option is used together
	      with --retry.

	      Added in 7.52.0.

       --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.

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

	      Added in 7.12.3.

       --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.

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

	      Added in 7.12.3.

       --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.

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

	      Added in 7.12.3.

       --sasl-ir
	      Enable initial response in SASL authentication.

	      Added in 7.31.0.

       --service-name <name>
	      This option allows you to change the service name for SPNEGO.

	      Examples:	   --negotiate	  --service-name   sockd   would   use
	      sockd/server-name.

	      Added in 7.43.0.

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

       -s, --silent
	      Silent  or  quiet	 mode. Don't show progress meter or error mes-
	      sages.  Makes Curl mute. It will still output the data  you  ask
	      for, potentially even to the terminal/stdout unless you redirect
	      it.

	      Use -S, --show-error in  addition	 to  this  option  to  disable
	      progress meter but still show error messages.

	      See also -v, --verbose and --stderr.

       --socks4 <host[:port]>
	      Use the specified SOCKS4 proxy. If the port number is not speci-
	      fied, 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
	      socks4 proxy with -x, --proxy using a socks4:// protocol prefix.

	      Since 7.52.0, --preproxy can be used to specify a SOCKS proxy at
	      the  same	 time -x, --proxy is used with an HTTP/HTTPS proxy. In
	      such a case curl first connects to the SOCKS proxy and then con-
	      nects (through SOCKS) to the HTTP or HTTPS proxy.

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

	      Added in 7.15.2.

       --socks4a <host[:port]>
	      Use the specified SOCKS4a proxy. If the port number is not spec-
	      ified, 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
	      socks4a proxy with -x, --proxy using a socks4a:// protocol  pre-
	      fix.

	      Since 7.52.0, --preproxy can be used to specify a SOCKS proxy at
	      the same time -x, --proxy is used with an HTTP/HTTPS  proxy.  In
	      such a case curl first connects to the SOCKS proxy and then con-
	      nects (through SOCKS) to the HTTP or HTTPS proxy.

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

	      Added in 7.18.0.

       --socks5-gssapi-nec
	      As part of the GSS-API 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.

       --socks5-gssapi-service <name>
	      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-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.

	      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.

	      Since 7.52.0, --preproxy can be used to specify a SOCKS proxy at
	      the same time -x, --proxy is used with an HTTP/HTTPS  proxy.  In
	      such a case curl first connects to the SOCKS proxy and then con-
	      nects (through SOCKS) to the HTTP or HTTPS proxy.

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

	      Added in 7.18.0.

       --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.

	      Since 7.52.0, --preproxy can be used to specify a SOCKS proxy at
	      the  same	 time -x, --proxy is used with an HTTP/HTTPS proxy. In
	      such a case curl first connects to the SOCKS proxy and then con-
	      nects (through SOCKS) to the HTTP or HTTPS proxy.

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

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

	      Added in 7.18.0.

       -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, --speed-time and is 30 if not set.

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

       -y, --speed-time <seconds>
	      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,
	      --speed-limit.

	      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.

       --ssl-allow-beast
	      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 workarounds known to cause interop-
	      erability 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.

       --ssl-no-revoke
	      (WinSSL) This option tells curl to disable  certificate  revoca-
	      tion checks.  WARNING: this option loosens the SSL security, and
	      by using this flag you ask for exactly that.

	      Added in 7.44.0.

       --ssl-reqd
	      (FTP IMAP POP3 SMTP) Require SSL/TLS for the connection.	Termi-
	      nates the connection if the server doesn't support SSL/TLS.

	      This option was formerly known as --ftp-ssl-reqd.

	      Added in 7.20.0.

       --ssl  (FTP  IMAP  POP3	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.

	      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.

	      Added in 7.20.0.

       -2, --sslv2
	      (SSL) Forces curl to use SSL version 2 when negotiating  with  a
	      remote  SSL  server.  Sometimes curl is built without SSLv2 sup-
	      port. SSLv2 is widely considered insecure (see RFC 6176).

	      See also --http1.1 and --http2. -2, --sslv2  requires  that  the
	      underlying  libcurl  was built to support TLS. This option over-
	      rides -3, --sslv3 and -1, --tlsv1 and --tlsv1.1 and --tlsv1.2.

       -3, --sslv3
	      (SSL) Forces curl to use SSL version 3 when negotiating  with  a
	      remote  SSL  server.  Sometimes curl is built without SSLv3 sup-
	      port. SSLv3 is widely considered insecure (see RFC 7568).

	      See also --http1.1 and --http2. -3, --sslv3  requires  that  the
	      underlying  libcurl  was built to support TLS. This option over-
	      rides -2, --sslv2 and -1, --tlsv1 and --tlsv1.1 and --tlsv1.2.

       --stderr
	      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.

	      See also -v, --verbose and -s, --silent.

       --tcp-fastopen
	      Enable use of TCP Fast Open (RFC7413).

	      Added in 7.49.0.

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

	      Since 7.50.2, curl sets this option by default and you  need  to
	      explictitly switch it off if you don't want it on.

	      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.

       --tftp-no-options
	      (TFTP) Tells curl not to send TFTP options requests.

	      This  option  improves  interop with some legacy servers that do
	      not acknowledge or properly implement TFTP  options.  When  this
	      option is used --tftp-blksize is ignored.

	      Added in 7.48.0.

       -z, --time-cond <time>
	      (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.

       --tlsauthtype <type>
	      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.

       --tlspassword
	      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 <name>
	      Set  username  for use with the TLS authentication method speci-
	      fied with --tlsauthtype. Requires	 that  --tlspassword  also  is
	      set.

	      Added in 7.21.4.

       --tlsv1.0
	      (TLS)  Forces  curl  to use TLS version 1.0 when connecting to a
	      remote TLS server.

	      Added in 7.34.0.

       --tlsv1.1
	      (TLS) Forces curl to use TLS version 1.1 when  connecting	 to  a
	      remote TLS server.

	      Added in 7.34.0.

       --tlsv1.2
	      (TLS)  Forces  curl  to use TLS version 1.2 when connecting to a
	      remote TLS server.

	      Added in 7.34.0.

       --tlsv1.3
	      (TLS) Forces curl to use TLS version 1.3 when  connecting	 to  a
	      remote TLS server.

	      Note that TLS 1.3 is only supported by a subset of TLS backends.
	      At the time of writing this, those are BoringSSL and NSS only.

	      Added in 7.52.0.

       -1, --tlsv1
	      (SSL) Tells curl to use TLS version 1.x when negotiating with  a
	      remote TLS server. That means TLS version 1.0, 1.1 or 1.2.

	      See  also	 --http1.1  and --http2. -1, --tlsv1 requires that the
	      underlying libcurl was built to support TLS. This	 option	 over-
	      rides --tlsv1.1 and --tlsv1.2 and --tlsv1.3.

       --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-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.

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

	      This option overrides --trace and -v, --verbose.

       --trace-time
	      Prepends	a  time	 stamp to each trace or verbose line that curl
	      displays.

	      Added in 7.14.0.

       --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.  Use  "%"  as
	      filename to have the output sent to stderr.

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

	      This option overrides -v, --verbose and --trace-ascii.

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

	      Added in 7.40.0.

       -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, --upload-file for each URL on the com-
	      mand line. Each -T, --upload-file + URL pair specifies  what  to
	      upload  and  to  where. curl also supports "globbing" of the -T,
	      --upload-file argument, meaning that  you	 can  upload  multiple
	      files  to a single URL by using the same URL globbing style sup-
	      ported in the URL, like this:

	       curl --upload-file "{file1,file2}" http://www.example.com

	      or even

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

	      When uploading to an SMTP server: the uploaded data  is  assumed
	      to be RFC 5322 formatted. It has to feature the necessary set of
	      headers and mail body formatted correctly by the	user  as  curl
	      will not transcode nor encode it further in any way.

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

	      If the given URL is missing a scheme name (such as "http://"  or
	      "ftp://"	etc) then curl will make a guess based on the host. If
	      the outermost sub-domain name matches  DICT,  FTP,  IMAP,	 LDAP,
	      POP3  or	SMTP  then  that protocol will be used, otherwise HTTP
	      will be used. Since 7.45.0 guessing can be disabled by setting a
	      default protocol, see --proto-default for details.

	      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.

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

       -A, --user-agent <name>
	      (HTTP) Specify the User-Agent string to send to the HTTP server.
	      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.

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

	      If  you  simply  specify	the  user name, curl will prompt for a
	      password.

	      The user name and passwords are split up	on  the	 first	colon,
	      which  makes  it impossible to use a colon in the user name with
	      this option. The password can, still.

	      When using Kerberos V5 with a Windows based  server  you	should
	      include  the  Windows domain name in the user name, in order for
	      the server to successfully obtain	 a  Kerberos  Ticket.  If  you
	      don't then the initial authentication handshake may fail.

	      When  using  NTLM,  the user name can be specified simply as the
	      user name, without the domain, if there is a single  domain  and
	      forest in your setup for example.

	      To  specify  the domain name use either Down-Level Logon Name or
	      UPN (User Principal Name) formats. For example, EXAMPLE\user and
	      user@example.com respectively.

	      If  you  use a Windows SSPI-enabled curl binary and perform Ker-
	      beros V5, Negotiate, NTLM or Digest authentication then you  can
	      tell  curl  to select the user name and password from your envi-
	      ronment by specifying a single colon with this option: "-u :".

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

       -v, --verbose
	      Makes curl verbose during the operation.	Useful	for  debugging
	      and  seeing  what's  going  on "under the hood". 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.

	      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.

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

	      See also	-i,  --include.	 This  option  overrides  --trace  and
	      --trace-ascii.

       -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    SSL versions of various protocols are supported, such  as
		     HTTPS, FTPS, POP3S and so on.

	      libz   Automatic	decompression of compressed files over HTTP is
		     supported.

	      NTLM   NTLM authentication 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.  Asynchronous
		     name  resolves can be done using either the c-ares or the
		     threaded resolver backends.

	      SPNEGO SPNEGO authentication is supported.

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

	      IDN    This curl supports IDN - international domain names.

	      GSS-API
		     GSS-API is supported.

	      SSPI   SSPI is supported.

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

	      HTTP2  HTTP/2 support has been built-in.

	      UnixSockets
		     Unix sockets support is provided.

	      HTTPS-proxy
		     This curl is built to support HTTPS proxy.

	      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).

	      PSL    PSL  is  short for Public Suffix List and means that this
		     curl has been built with  knowledge  about	 "public  suf-
		     fixes".

       -w, --write-out <format>
	      Make curl display information on stdout after a completed trans-
	      fer. The format is a string that may contain  plain  text	 mixed
	      with  any	 number of variables. The format can be specified as a
	      literal "string", or you can have curl read the  format  from  a
	      file  with  "@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  -O,  --remote-name or -o,
			     --output option. It's most useful in  combination
			     with  the -J, --remote-header-name option. (Added
			     in 7.26.0)

	      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)

	      http_version   The  http	version	 that  was  effectively	 used.
			     (Added in 7.50.0)

	      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)

	      proxy_ssl_verify_result
			     The result of the HTTPS proxy's SSL peer certifi-
			     cate verification that was requested. 0 means the
			     verification was successful. (Added in 7.52.0)

	      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)

	      scheme	     The URL scheme (sometimes called  protocol)  that
			     was effectively used (Added in 7.52.0)

	      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.

	      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.

       --xattr
	      When saving output to a file, this option tells  curl  to	 store
	      certain  file  metadata  in extended 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.

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 -x, --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.

	      Since 7.53.0, this environment variable disable the  proxy  even
	      if  specify  -x,	--proxy	 option. That is NO_PROXY=direct.exam-
	      ple.com  curl  -x	 http://proxy.example.com  http://direct.exam-
	      ple.com	  accesses    the    target    URL    directly,	   and
	      NO_PROXY=direct.example.com  curl	 -x   http://proxy.example.com
	      http://somewhere.example.com  accesses  the  target  URL through
	      proxy.


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      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.

       10     FTP  accept failed. While waiting for the server to connect back
	      when an active FTP session is used, an error code was sent  over
	      the control connection or similar.

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

       12     During an active FTP session while waiting  for  the  server  to
	      connect back to curl, the timeout expired.

       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.

       16     HTTP/2 error. A problem was detected in the HTTP2 framing layer.
	      This is somewhat generic and can be one out of several problems,
	      see the error message for details.

       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     Bad download resume. Couldn't continue an earlier aborted	 down-
	      load.

       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

       89     No connection available, the session will be queued

       90     SSL public key does not matched pinned public key

       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
       https://curl.haxx.se

SEE ALSO
       ftp(1), wget(1)



Curl 7.52.0			  16 Dec 2016			       curl(1)