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curl(1)                                    curl Manual                                    curl(1)

NAME
       curl - transfer a URL

SYNOPSIS
       curl [options / URLs]

DESCRIPTION
       curl  is  a  tool  for transferring data from or to a server. It supports these protocols:
       DICT, FILE, FTP, FTPS, GOPHER, GOPHERS, HTTP, HTTPS, IMAP, IMAPS, LDAP, LDAPS, MQTT, POP3,
       POP3S,  RTMP,  RTMPS, RTSP, SCP, SFTP, SMB, SMBS, SMTP, SMTPS, TELNET or TFTP. The command
       is designed to work without user interaction.

       curl offers a busload of useful tricks like proxy support, user  authentication,  FTP  up-
       load,  HTTP post, SSL connections, cookies, file transfer resume and more. As you will see
       below, the number of features will make your head spin.

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

URL
       The URL syntax is protocol-dependent. You find a detailed description in RFC 3986.

       You can specify multiple URLs or parts of URLs by writing  part  sets  within  braces  and
       quoting the URL 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 sequen-
       tial manner in the specified order. You can specify command line options  and  URLs  mixed
       and in any order on the command line.

       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 example, for host names starting with "ftp." curl will assume  you
       want to speak FTP.

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

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

OUTPUT
       If  not  told  otherwise, curl writes the received data to stdout. It can be instructed to
       instead save that data into a local file, using the -o, --output or -O, --remote-name  op-
       tions.  If curl is given multiple URLs to transfer on the command line, it similarly needs
       multiple options for where to save them.

       curl does not parse or otherwise "understand" the content it gets or writes as output.  It
       does  no  encoding or decoding, unless explicitly asked to with dedicated command line op-
       tions.

PROTOCOLS
       curl supports numerous protocols, or put in URL terms: schemes. Your particular build  may
       not support them all.

       DICT   Lets you lookup words using online dictionaries.

       FILE   Read  or  write  local files. curl does not support accessing file:// URL remotely,
              but when running on Microsoft Windows using the native UNC approach will work.

       FTP(S) curl supports the File Transfer Protocol with a lot of tweaks and levers.  With  or
              without using TLS.

       GOPHER(S)
              Retrieve files.

       HTTP(S)
              curl  supports HTTP with numerous options and variations. It can speak HTTP version
              0.9, 1.0, 1.1, 2 and 3 depending on build options and the correct command line  op-
              tions.

       IMAP(S)
              Using  the mail reading protocol, curl can "download" emails for you. With or with-
              out using TLS.

       LDAP(S)
              curl can do directory lookups for you, with or without TLS.

       MQTT   curl supports MQTT version 3. Downloading over MQTT equals "subscribe" to  a  topic
              while uploading/posting equals "publish" on a topic. MQTT over TLS is not supported
              (yet).

       POP3(S)
              Downloading from a pop3 server means getting a mail. With or without using TLS.

       RTMP(S)
              The Realtime Messaging Protocol is primarily used to  server  streaming  media  and
              curl can download it.

       RTSP   curl supports RTSP 1.0 downloads.

       SCP    curl supports SSH version 2 scp transfers.

       SFTP   curl supports SFTP (draft 5) done over SSH version 2.

       SMB(S) curl supports SMB version 1 for upload and download.

       SMTP(S)
              Uploading contents to an SMTP server means sending an email. With or without TLS.

       TELNET Telling  curl  to  fetch  a telnet URL starts an interactive session where it sends
              what it reads on stdin and outputs what the server sends it.

       TFTP   curl can do TFTP downloads and uploads.

PROGRESS METER
       curl normally displays a progress meter during operations, indicating the amount of trans-
       ferred  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 opera-
       tion and it is about to write data to the terminal, it disables the progress meter as oth-
       erwise it would mess up the output mixing progress meter and response data.

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

       This does not apply to 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 do not 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 same option name but prefix it with "no-".  However,  in
       this list we mostly only list and show the --option version of them.

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

              Example:
               curl --abstract-unix-socket socketpath https://example.com

              See also --unix-socket. Added in 7.53.0.

       --alt-svc <file name>
              (HTTPS)  This option enables the alt-svc parser in curl. If the file name points to
              an existing alt-svc cache file, that will be used. After a completed transfer,  the
              cache will be saved to the file name again if it has been modified.

              Specify  a  ""  file  name (zero length) to avoid loading/saving and make curl just
              handle the cache in memory.

              If this option is used several times, curl will load contents from  all  the  files
              but the last one will be used for saving.

              Example:
               curl --alt-svc svc.txt https://example.com

              See also --resolve and --connect-to. Added in 7.64.1.

       --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 re-
              quire 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.

              Example:
               curl --anyauth --user me:pwd https://example.com

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

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

              Example:
               curl --upload-file local --append ftp://example.com/

              See also -r, --range and -C, --continue-at.

       --aws-sigv4 <provider1[:provider2[:region[:service]]]>
              Use AWS V4 signature authentication in the transfer.

              The  provider argument is a string that is used by the algorithm when creating out-
              going authentication headers.

              The region argument is a string that points to a geographic  area  of  a  resources
              collection (region-code) when the region name is omitted from the endpoint.

              The  service  argument  is  a  string that points to a function provided by a cloud
              (service-code) when the service name is omitted from the endpoint.

              Example:
               curl --aws-sigv4 "aws:amz:east-2:es" --user "key:secret" https://example.com

              See also --basic and -u, --user. Added in 7.75.0.

       --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.

              Example:
               curl -u name:password --basic https://example.com

              See also --proxy-basic.

       --cacert <file>
              (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 vari-
              able.

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

              If curl is built against the NSS SSL library, the  NSS  PEM  PKCS#11  module  (lib-
              nsspem.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.

              (Schannel  only)  This  option is supported for Schannel in Windows 7 or later with
              libcurl 7.60 or later. This option is supported  for  backward  compatibility  with
              other SSL engines; instead it is recommended to use Windows' store of root certifi-
              cates (the default for Schannel).

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

              Example:
               curl --cacert CA-file.txt https://example.com

              See also --capath and -k, --insecure.

       --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.

              Example:
               curl --capath /local/directory https://example.com

              See also --cacert and -k, --insecure.

       --cert-status
              (TLS)  Tells  curl to verify the status of the server certificate by using the Cer-
              tificate 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 certificate has been revoked, or no re-
              sponse at all is received, the verification fails.

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

              Example:
               curl --cert-status https://example.com

              See also --pinnedpubkey. Added in 7.41.0.

       --cert-type <type>
              (TLS) Tells curl what type the provided client certificate is using. PEM, DER,  ENG
              and P12 are recognized types. If not specified, PEM is assumed.

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

              Example:
               curl --cert-type PEM --cert file https://example.com

              See also -E, --cert, --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 protocol. The certificate must be in  PKCS#12
              format  if  using Secure Transport, or PEM format if using any other engine. If the
              optional password is not 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  indepen-
              dently.

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

              If  curl is built against OpenSSL library, and the engine pkcs11 is available, then
              a PKCS#11 URI (RFC 7512) can be used to specify a certificate located in a  PKCS#11
              device.  A string beginning with "pkcs11:" will be interpreted as a PKCS#11 URI. If
              a PKCS#11 URI is provided, then the --engine option will be set as "pkcs11" if none
              was provided and the --cert-type option will be set as "ENG" if none was provided.

              (iOS  and  macOS only) If curl is built against Secure Transport, then the certifi-
              cate string can either be the name of a certificate/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.

              (Schannel  only)  Client  certificates  must be specified by a path expression to a
              certificate store. (Loading PFX is not supported; you can  import  it  to  a  store
              first). You can use "<store location>\<store name>\<thumbprint>" to refer to a cer-
              tificate   in   the   system   certificates   store,    for    example,    "Curren-
              tUser\MY\934a7ac6f8a5d579285a74fa61e19f23ddfe8d7a".  Thumbprint  is usually a SHA-1
              hex string which you can see in certificate details. Following store locations  are
              supported:  CurrentUser,  LocalMachine, CurrentService, Services, CurrentUserGroup-
              Policy, LocalMachineGroupPolicy, LocalMachineEnterprise.

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

              Example:
               curl --cert certfile --key keyfile https://example.com

              See also --cert-type, --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.se/docs/ssl-ciphers.html

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

              Example:
               curl --ciphers ECDHE-ECDSA-AES256-CCM8 https://example.com

              See also --tlsv1.3.

       --compressed-ssh
              (SCP  SFTP) Enables built-in SSH compression.  This is a request, not an order; the
              server may or may not do it.

              Example:
               curl --compressed-ssh sftp://example.com/

              See also --compressed. Added in 7.56.0.

       --compressed
              (HTTP) Request a compressed response using one of the algorithms curl supports, and
              automatically decompress the content. Headers are not modified.

              If  this option is used and the server sends an unsupported encoding, curl will re-
              port an error. This is a request, not an order; the server may or may  not  deliver
              data compressed.

              Example:
               curl --compressed https://example.com

              See also --compressed-ssh.

       -K, --config <file>
              Specify  a  text file to read curl arguments from. The command line arguments found
              in the text file will be used as if they were provided on the command line.

              Options and their parameters must be specified on the same line in the file,  sepa-
              rated 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 contains whitespace (or starts with : or =), 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 ig-
              nored.

              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.se/docs/"

               # --- 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 ---

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

              1) "$CURL_HOME/.curlrc"

              2) "$XDG_CONFIG_HOME/.curlrc" (Added in 7.73.0)

              3) "$HOME/.curlrc"

              4) Windows: "%USERPROFILE%\.curlrc"

              5) Windows: "%APPDATA%\.curlrc"

              6) Windows: "%USERPROFILE%\Application Data\.curlrc"

              7) Non-windows: use getpwuid to find the home directory

              8)  On  windows,  if  it  finds no .curlrc file in the sequence described above, it
              checks for one in the same dir the curl executable is placed.

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

              Example:
               curl --config file.txt https://example.com

              See also -q, --disable.

       --connect-timeout <fractional seconds>
              Maximum time in seconds that you allow curl's connection to take.  This only limits
              the  connection phase, so if curl connects 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.

              Examples:
               curl --connect-timeout 20 https://example.com
               curl --connect-timeout 3.14 https://example.com

              See also -m, --max-time.

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

              For a request to the given HOST1:PORT1 pair, connect to HOST2:PORT2 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 hostname/port that is used for TLS/SSL
              (e.g. SNI, certificate verification) or for the application protocols. "HOST1"  and
              "PORT1"  may  be the empty string, meaning "any host/port". "HOST2" and "PORT2" may
              also be the empty string, meaning "use the request's original host/port".

              A "host" specified to this option is compared as a string, so it needs to match the
              name  used  in  request  URL. It can be either numerical such as "127.0.0.1" or the
              full host name such as "example.org".

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

              Example:
               curl --connect-to example.com:443:example.net:8443 https://example.com

              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.

              Examples:
               curl -C - https://example.com
               curl -C 400 https://example.com

              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 operations. 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 cannot be created or written to, the whole curl operation will
              not 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.

              Examples:
               curl -c store-here.txt https://example.com
               curl -c store-here.txt -b read-these https://example.com

              See also -b, --cookie.

       -b, --cookie <data|filename>
              (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  are  using
              this  in combination with the -L, --location option or do multiple URL transfers on
              the same invoke. If the file name is exactly a minus ("-"), curl will instead  read
              the contents from stdin.

              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.

              If  you  use the Set-Cookie file format and do not specify a domain then the cookie
              is not sent since the domain will never match. To address this,  set  a  domain  in
              Set-Cookie  line  (doing that will include sub-domains) or preferably: use the Net-
              scape format.

              This option can be used multiple times.

              Users 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.

              Examples:
               curl -b cookiefile https://example.com
               curl -b cookiefile -c cookiefile https://example.com

              See also -c, --cookie-jar and -j, --junk-session-cookies.

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

              Created dirs are made with mode 0750 on unix style file systems.

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

              Example:
               curl --create-dirs --output local/dir/file https://example.com

              See also --ftp-create-dirs and --output-dir.

       --create-file-mode <mode>
              (SFTP SCP FILE) When curl is used to create files remotely using one  of  the  sup-
              ported  protocols,  this  option  allows the user to set which 'mode' to set on the
              file at creation time, instead of the default 0644.

              This option takes an octal number as argument.

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

              Example:
               curl --create-file-mode 0777 -T localfile sftp://example.com/new

              See also --ftp-create-dirs. Added in 7.75.0.

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

              (SMTP added in 7.40.0)

              Example:
               curl --crlf -T file ftp://example.com/

              See also -B, --use-ascii.

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

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

              Example:
               curl --crlfile rejects.txt https://example.com

              See also --cacert and --capath.

       --curves <algorithm list>
              (TLS) Tells curl to request specific curves to use during SSL session establishment
              according to RFC 8422, 5.1.  Multiple algorithms can be provided by separating them
              with  ":"  (e.g.   "X25519:P-521").   The parameter is available identically in the
              "openssl s_client/s_server" utilities.

              --curves allows a OpenSSL powered curl to make  SSL-connections  with  exactly  the
              (EC)  curve requested by the client, avoiding nontransparent client/server negotia-
              tions.

              If this option is set, the default curves list built into openssl will be ignored.

              Example:
               curl --curves X25519 https://example.com

              See also --ciphers. Added in 7.73.0.

       --data-ascii <data>
              (HTTP) This is just an alias for -d, --data.

              Example:
               curl --data-ascii @file https://example.com

              See also --data-binary, --data-raw and --data-urlencode.

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

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

              Like -d, --data the default content-type sent to the server  is  application/x-www-
              form-urlencoded. If you want the data to be treated as arbitrary binary data by the
              server then set  the  content-type  to  octet-stream:  -H  "Content-Type:  applica-
              tion/octet-stream".

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

              Example:
               curl --data-binary @filename https://example.com

              See also --data-ascii.

       --data-raw <data>
              (HTTP) This posts data similarly to -d, --data but without the special  interpreta-
              tion of the @ character.

              Examples:
               curl --data-raw "hello" https://example.com
               curl --data-raw "@at@at@" https://example.com

              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 separa-
              tor and a content specification. The <data> part can be passed to curl using one of
              the following syntaxes:

              content
                     This will make curl URL-encode the content and pass that on. Just be careful
                     so  that  the content does not 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.

       Examples:
        curl --data-urlencode name=val https://example.com
        curl --data-urlencode =encodethis https://example.com
        curl --data-urlencode name@file https://example.com
        curl --data-urlencode @fileonly https://example.com

       See also -d, --data and --data-raw.

       -d, --data <data>
              (HTTP MQTT) 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  con-
              tent-type application/x-www-form-urlencoded. Compare to -F, --form.

              --data-raw  is  almost the same but does not have a special interpretation of the @
              character. To post data purely binary, you should instead use the --data-binary op-
              tion. To URL-encode the value of a form field you may use --data-urlencode.

              If  any  of these options is used more than once on the same command line, the data
              pieces specified will be  merged  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. Posting data from a
              file named 'foobar' would thus be done with -d, --data @foobar. When -d, --data  is
              told  to read from a file like that, carriage returns and newlines will be stripped
              out. If you do not want the @  character  to  have  a  special  interpretation  use
              --data-raw instead.

              Examples:
               curl -d "name=curl" https://example.com
               curl -d "name=curl" -d "tool=cmdline" https://example.com
               curl -d @filename https://example.com

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

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

              none   Do not allow any delegation.

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

              always Unconditionally allow the server to delegate.

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

       Example:
        curl --delegation "none" https://example.com

       See also -k, --insecure and --ssl.

       --digest
              (HTTP) Enables HTTP Digest authentication. This is an  authentication  scheme  that
              prevents the password from being sent over the wire in clear text. Use this in com-
              bination 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.

              Example:
               curl -u name:password --digest https://example.com

              See also -u, --user, --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  be-
              fore  using  PORT, but with this option, it will use PORT right away. EPRT and LPRT
              are extensions to the original FTP protocol, and may not work on all  servers,  but
              they enable more functionality in a better way than the traditional PORT command.

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

              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.

              Example:
               curl --disable-eprt ftp://example.com/

              See also --disable-epsv and -P, --ftp-port.

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

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

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

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

              Example:
               curl --disable-epsv ftp://example.com/

              See also --disable-eprt and -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.

              Example:
               curl -q https://example.com

              See also -K, --config.

       --disallow-username-in-url
              (HTTP) This tells curl to exit if passed a url containing a username. This is prob-
              ably most useful when the URL is being provided at run-time or similar.

              Example:
               curl --disallow-username-in-url https://example.com

              See also --proto. Added in 7.61.0.

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

              Example:
               curl --dns-interface eth0 https://example.com

              See also --dns-ipv4-addr and --dns-ipv6-addr. --dns-interface requires that the un-
              derlying 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  ad-
              dress.

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

              Example:
               curl --dns-ipv4-addr 10.1.2.3 https://example.com

              See also --dns-interface and --dns-ipv6-addr. --dns-ipv4-addr requires that the un-
              derlying 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 ad-
              dress.

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

              Example:
               curl --dns-ipv6-addr 2a04:4e42::561 https://example.com

              See also --dns-interface and --dns-ipv4-addr. --dns-ipv6-addr requires that the un-
              derlying 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 commas. Port numbers may also  optionally  be
              given as :<port-number> after each IP address.

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

              Example:
               curl --dns-servers 192.168.0.1,192.168.0.2 https://example.com

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

       --doh-cert-status
              Same as --cert-status but used for DoH (DNS-over-HTTPS).

              Example:
               curl --doh-cert-status --doh-url https://doh.example https://example.com

              See also --doh-insecure. Added in 7.76.0.

       --doh-insecure
              Same as -k, --insecure but used for DoH (DNS-over-HTTPS).

              Example:
               curl --doh-insecure --doh-url https://doh.example https://example.com

              See also --doh-url. Added in 7.76.0.

       --doh-url <URL>
              Specifies which DNS-over-HTTPS (DoH) server to use to resolve hostnames, instead of
              using the default name resolver mechanism. The URL must be HTTPS.

              Some  SSL  options  that you set for your transfer will apply to DoH since the name
              lookups take place over SSL. However, the certificate verification settings are not
              inherited  and  can be controlled separately via --doh-insecure and --doh-cert-sta-
              tus.

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

              Example:
               curl --doh-url https://doh.example https://example.com

              See also --doh-insecure. Added in 7.62.0.

       -D, --dump-header <filename>
              (HTTP FTP) Write the received protocol headers to the specified file. If no headers
              are received, the use of this option will create an empty file.

              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.

              Example:
               curl --dump-header store.txt https://example.com

              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.

              Example:
               curl --egd-file /random/here https://example.com

              See also --random-file.

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

              Example:
               curl --engine flavor https://example.com

              See also --ciphers and --curves.

       --etag-compare <file>
              (HTTP) This option makes a conditional HTTP request for the specific ETag read from
              the given file by sending a custom If-None-Match header using the stored ETag.

              For correct results, make sure that the specified file contains only a single  line
              with the desired ETag. An empty file is parsed as an empty ETag.

              Use  the  option  --etag-save  to first save the ETag from a response, and then use
              this option to compare against the saved ETag in a subsequent request.

              Example:
               curl --etag-compare etag.txt https://example.com

              See also --etag-save and -z, --time-cond. Added in 7.68.0.

       --etag-save <file>
              (HTTP) This option saves an HTTP ETag to the specified file. An ETag is  a  caching
              related header, usually returned in a response.

              If no ETag is sent by the server, an empty file is created.

              Example:
               curl --etag-save storetag.txt https://example.com

              See also --etag-compare. Added in 7.68.0.

       --expect100-timeout <seconds>
              (HTTP)  Maximum  time in seconds that you allow curl to wait for a 100-continue re-
              sponse 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.

              Example:
               curl --expect100-timeout 2.5 -T file https://example.com

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

       --fail-early
              Fail and exit on the first detected transfer 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 successful transfers.

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

              This option is global and does not need to be specified for each use of -:, --next.

              This  option  does  not imply -f, --fail, which causes transfers to fail due to the
              server's HTTP status code. You can combine the two options, however note -f, --fail
              is not global and is therefore contained by -:, --next.

              Example:
               curl --fail-early https://example.com https://two.example

              See also -f, --fail and --fail-with-body. Added in 7.52.0.

       --fail-with-body
              (HTTP)  Return  an  error  on  server errors where the HTTP response code is 400 or
              greater). In normal cases when an HTTP server fails to deliver a document,  it  re-
              turns  an  HTML document stating so (which often also describes why and more). This
              flag will still allow curl to output and save that content but also to return error
              22.

              This is an alternative option to -f, --fail which makes curl fail for the same cir-
              cumstances but without saving the content.

              Example:
               curl --fail-with-body https://example.com

              See also -f, --fail. Added in 7.76.0.

       -f, --fail
              (HTTP) Fail silently (no output at all) on server errors. This is  mostly  done  to
              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 prevent curl from out-
              putting that and return error 22.

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

              Example:
               curl --fail https://example.com

              See also --fail-with-body.

       --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  hand-
              shake.

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

              Example:
               curl --false-start https://example.com

              See also --tcp-fastopen. Added in 7.42.0.

       --form-escape
              (HTTP) Tells curl to pass on names of multipart form fields and files  using  back-
              slash-escaping instead of percent-encoding.

              Example:
               curl --form-escape --form 'field\name=curl' 'file=@load"this' https://example.com

              See also -F, --form. Added in 7.81.0.

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

              Example:
               curl --form-string "data" https://example.com

              See also -F, --form.

       -F, --form <name=content>
              (HTTP  SMTP IMAP) For HTTP protocol family, 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.

              For  SMTP and IMAP protocols, this is the means to compose a multipart mail message
              to transmit.

              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.

              Tell curl to read content from stdin instead of a file by using - as filename. This
              goes  for  both @ and < constructs. When stdin is used, the contents is buffered in
              memory first by curl to determine its size and allow a possible resend. Defining  a
              part's  data from a named non-regular file (such as a named pipe or similar) is un-
              fortunately not subject to buffering and will be effectively read  at  transmission
              time;  since the full size is unknown before the transfer starts, such data is sent
              as chunks by HTTP and rejected by IMAP.

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

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

              Example: send your name and shoe size in two text fields to the server:

               curl -F name=John -F shoesize=11 https://example.com/

              Example:  send  your  essay  in a text field to the server. Send it as a plain text
              field, but get the contents for it from a local file:

               curl -F "story=<hugefile.txt" https://example.com/

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

               curl -F "web=@index.html;type=text/html" 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 double-quotes like:

               curl -F "file=@\"local,file\";filename=\"name;in;post\"" example.com

              or

               curl -F 'file=@"local,file";filename="name;in;post"' example.com

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

              Quoting  must  also  be  applied  to non-file data if it contains semicolons, lead-
              ing/trailing spaces or leading double quotes:

               curl -F 'colors="red; green; blue";type=text/x-myapp' example.com

              You can add custom headers to the field by setting headers=, like

                curl -F "submit=OK;headers=\"X-submit-type: OK\"" example.com

              or

                curl -F "submit=OK;headers=@headerfile" example.com

              The headers= keyword may appear more that once and above notes about quoting apply.
              When headers are read from a file, Empty lines and lines starting with '#' are com-
              ments and ignored; each header can be folded by splitting  between  two  words  and
              starting the continuation line with a space; embedded carriage-returns and trailing
              spaces are stripped.  Here is an example of a header file contents:

                # This file contain two headers.
                X-header-1: this is a header

                # The following header is folded.
                X-header-2: this is
                 another header

              To support sending multipart mail messages, the syntax is extended as follows:
              - name can be omitted: the equal sign is the first character of the argument,
              - if data starts with '(', this signals to start a new multipart: it  can  be  fol-
              lowed by a content type specification.
              - a multipart can be terminated with a '=)' argument.

              Example:  the  following  command  sends an SMTP mime email consisting in an inline
              part in two alternative formats: plain text and HTML. It attaches a text file:

               curl -F '=(;type=multipart/alternative' \
                    -F '=plain text message' \
                    -F '= <body>HTML message</body>;type=text/html' \
                    -F '=)' -F '=@textfile.txt' ...  smtp://example.com

              Data can be encoded for transfer using encoder=. Available encodings are binary and
              8bit  that  do nothing else than adding the corresponding Content-Transfer-Encoding
              header, 7bit that only rejects 8-bit characters  with  a  transfer  error,  quoted-
              printable and base64 that encodes data according to the corresponding schemes, lim-
              iting lines length to 76 characters.

              Example: send multipart mail with a quoted-printable text message and a base64  at-
              tached file:

               curl -F '=text message;encoder=quoted-printable' \
                    -F '=@localfile;encoder=base64' ... smtp://example.com

              See further examples and details in the MANUAL.

              This option can be used multiple times.

              Example:
               curl --form "name=curl" --form "file=@loadthis" https://example.com

              See  also  -d,  --data,  --form-string and --form-escape. This option overrides -d,
              --data and -I, --head and -T, --upload-file.

       --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.

              Example:
               curl --ftp-account "mr.robot" ftp://example.com/

              See also -u, --user.

       --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.

              Example:
               curl --ftp-alternative-to-user "U53r" ftp://example.com

              See also --ftp-account and -u, --user.

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

              Example:
               curl --ftp-create-dirs -T file ftp://example.com/remote/path/file

              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 following alternatives:

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

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

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

       Examples:
        curl --ftp-method multicwd ftp://example.com/dir1/dir2/file
        curl --ftp-method nocwd ftp://example.com/dir1/dir2/file
        curl --ftp-method singlecwd ftp://example.com/dir1/dir2/file

       See also -l, --list-only.

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

              If this option is used several times, only the first one is used.  Undoing  an  en-
              forced  passive  really is not 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.

              Example:
               curl --ftp-pasv ftp://example.com/

              See also --disable-epsv.

       -P, --ftp-port <address>
              (FTP)  Reverses the default initiator/listener roles when connecting 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
                     e.g. "eth0" to specify which interface's IP address you want  to  use  (Unix
                     only)

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

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

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

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

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

       Examples:
        curl -P - ftp:/example.com
        curl -P eth0 ftp:/example.com
        curl -P 192.168.0.2 ftp:/example.com

       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.

              Example:
               curl --ftp-pret ftp://example.com/

              See also -P, --ftp-port and --ftp-pasv.

       --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.

              Since curl 7.74.0 this option is enabled by default.

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

              Example:
               curl --ftp-skip-pasv-ip ftp://example.com/

              See also --ftp-pasv.

       --ftp-ssl-ccc-mode <active/passive>
              (FTP)  Sets  the CCC mode. The passive mode will not initiate the shutdown, but in-
              stead 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.

              Example:
               curl --ftp-ssl-ccc-mode active --ftp-ssl-ccc ftps://example.com/

              See also --ftp-ssl-ccc.

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

              Example:
               curl --ftp-ssl-ccc ftps://example.com/

              See also --ssl and --ftp-ssl-ccc-mode.

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

              Example:
               curl --ftp-ssl-control ftp://example.com

              See also --ssl.

       -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 '?' sepa-
              rator.

              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 does not make sense, but you should then instead enforce the alterna-
              tive method you prefer.

              Examples:
               curl --get https://example.com
               curl --get -d "tool=curl" -d "age=old" https://example.com
               curl --get -I -d "tool=curl" https://example.com

              See also -d, --data and -X, --request.

       -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 curl itself interpret
              them. Note that these letters are not normal legal URL contents but they should  be
              encoded according to the URI standard.

              Example:
               curl -g "https://example.com/{[]}}}}"

              See also -K, --config and -q, --disable.

       --happy-eyeballs-timeout-ms <milliseconds>
              Happy  Eyeballs  is an algorithm that attempts to connect to both IPv4 and IPv6 ad-
              dresses for dual-stack hosts, giving IPv6 a head-start of the specified  number  of
              milliseconds.  If  the IPv6 address cannot be connected to within that time, then a
              connection attempt is made to the IPv4 address in parallel. The first connection to
              be established is the one that is used.

              The  range  of suggested useful values is limited. Happy Eyeballs RFC 6555 says "It
              is RECOMMENDED that connection attempts be paced 150-250 ms apart to balance  human
              factors  against  network  load." libcurl currently defaults to 200 ms. Firefox and
              Chrome currently default to 300 ms.

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

              Example:
               curl --happy-eyeballs-timeout-ms 500 https://example.com

              See also -m, --max-time and --connect-timeout. Added in 7.59.0.

       --haproxy-protocol
              (HTTP) Send a HAProxy PROXY protocol v1 header at the beginning of the  connection.
              This  is  used  by some load balancers and reverse proxies to indicate the client's
              true IP address and port.

              This option is primarily useful when sending test requests to a  service  that  ex-
              pects this header.

              Example:
               curl --haproxy-protocol https://example.com

              See also -x, --proxy. Added in 7.60.0.

       -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.

              Example:
               curl -I https://example.com

              See also -G, --get, -v, --verbose and --trace-ascii.

       -H, --header <header/@file>
              (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 ex-
              ternally 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 inter-
              nally set headers without knowing perfectly well what you are doing. Remove an  in-
              ternal  header  by  giving  a  replacement without content on the right side of the
              colon, as in: -H "Host:". If you send the custom  header  with  no-value  then  its
              header  must  be terminated with a semicolon, such as -H "X-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.

              This option can take an argument in @filename style, which then adds a  header  for
              each  line  in  the  input  file. Using @- will make curl read the header file from
              stdin. Added in 7.55.0.

              You need --proxy-header to send custom headers intended for a HTTP proxy. Added  in
              7.37.0.

              Passing  on  a "Transfer-Encoding: chunked" header when doing a HTTP request with a
              request body, will make curl send the data using chunked encoding.

              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.

              Examples:
               curl -H "X-First-Name: Joe" https://example.com
               curl -H "User-Agent: yes-please/2000" https://example.com
               curl -H "Host:" https://example.com

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

       -h, --help <category>
              Usage  help.  This  lists  all commands of the <category>.  If no arg was provided,
              curl will display the most important command line arguments.  If the argument "all"
              was  provided, curl will display all options available.  If the argument "category"
              was provided, curl will display all categories and their meanings.

              Example:
               curl --help all

              See also -v, --verbose.

       --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 connec-
              tion with the host unless the md5sums match.

              Example:
               curl --hostpubmd5 e5c1c49020640a5ab0f2034854c321a8 sftp://example.com/

              See also --hostpubsha256.

       --hostpubsha256 <sha256>
              (SFTP SCP) Pass a string containing a Base64-encoded  SHA256  hash  of  the  remote
              host's  public key. Curl will refuse the connection with the host unless the hashes
              match.

              Example:
               curl --hostpubsha256 NDVkMTQxMGQ1ODdmMjQ3MjczYjAyOTY5MmRkMjVmNDQ= sftp://example.com/

              See also --hostpubmd5. Added in 7.80.0.

       --hsts <file name>
              (HTTPS) This option enables HSTS for the transfer. If the file name  points  to  an
              existing  HSTS cache file, that will be used. After a completed transfer, the cache
              will be saved to the file name again if it has been modified.

              Specify a "" file name (zero length) to avoid loading/saving  and  make  curl  just
              handle HSTS in memory.

              If  this  option  is used several times, curl will load contents from all the files
              but the last one will be used for saving.

              Example:
               curl --hsts cache.txt https://example.com

              See also --proto. Added in 7.74.0.

       --http0.9
              (HTTP) Tells curl to be fine with HTTP version 0.9 response.

              HTTP/0.9 is a completely headerless response and therefore  you  can  also  connect
              with  this  to  non-HTTP  servers  and  still get a response since curl will simply
              transparently downgrade - if allowed.

              Since curl 7.66.0, HTTP/0.9 is disabled by default.

              Example:
               curl --http0.9 https://example.com

              See also --http1.1, --http2 and --http3. Added in 7.64.0.

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

              Example:
               curl --http1.0 https://example.com

              See also --http0.9 and --http1.1. This option overrides --http1.1 and --http2.

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

              Example:
               curl --http1.1 https://example.com

              See  also --http1.1 and --http0.9. 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  ver-
              sion in the TLS handshake.

              Example:
               curl --http2-prior-knowledge https://example.com

              See  also --http2 and --http3. --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.

              For  HTTPS,  this means curl will attempt to negotiate HTTP/2 in the TLS handshake.
              curl does this by default.

              For HTTP, this means curl will attempt to upgrade the request to HTTP/2  using  the
              Upgrade: request header.

              Example:
               curl --http2 https://example.com

              See  also  --http1.1  and --http3. --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.

       --http3
              (HTTP) WARNING: this option is experimental. Do not use in production.

              Tells  curl  to use HTTP version 3 directly to the host and port number used in the
              URL. A normal HTTP/3 transaction will be done to a host and then get redirected via
              Alt-Svc,  but  this  option allows a user to circumvent that when you know that the
              target speaks HTTP/3 on the given host and port.

              This option will make curl fail if a QUIC connection cannot be established, it can-
              not fall back to a lower HTTP version on its own.

              Example:
               curl --http3 https://example.com

              See  also  --http1.1  and --http2. --http3 requires that the underlying libcurl was
              built to support HTTP/3. This option overrides  --http1.1  and  -0,  --http1.0  and
              --http2 and --http2-prior-knowledge. Added in 7.66.0.

       --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 gigabytes.

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

              This option does not work for HTTP if libcurl was built to use hyper.

              Example:
               curl --ignore-content-length https://example.com

              See also --ftp-skip-pasv-ip.

       -i, --include
              Include the HTTP response headers in the output. The HTTP response headers can  in-
              clude  things  like  server  name,  cookies, date of the document, HTTP version and
              more...

              To view the request headers, consider the -v, --verbose option.

              Example:
               curl -i https://example.com

              See also -v, --verbose.

       -k, --insecure
              (TLS SFTP SCP) By default, every secure connection curl makes is verified to be se-
              cure  before the transfer takes place. This option makes curl skip the verification
              step and proceed without checking.

              When this option is not used for protocols using TLS, curl  verifies  the  server's
              TLS  certificate  before it continues: that the certificate contains the right name
              which matches the host name used in the URL  and  that  the  certificate  has  been
              signed by a CA certificate present in the cert store.  See this online resource for
              further details:
               https://curl.se/docs/sslcerts.html

              For SFTP and SCP,  this  option  makes  curl  skip  the  known_hosts  verification.
              known_hosts is a file normally stored in the user's home directory in the .ssh sub-
              directory, which contains host names and their public keys.

              WARNING: using this option makes the transfer insecure.

              Example:
               curl --insecure https://example.com

              See also --proxy-insecure, --cacert and --capath.

       --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.

              On  Linux  it  can  be  used  to specify a VRF, but the binary needs to either have
              CAP_NET_RAW  or  to  be  run  as  root.   More   information   about   Linux   VRF:
              https://www.kernel.org/doc/Documentation/networking/vrf.txt

              Example:
               curl --interface eth0 https://example.com

              See also --dns-interface.

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

              Example:
               curl --ipv4 https://example.com

              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.

              Example:
               curl --ipv6 https://example.com

              See also --http1.1 and --http2. This option overrides -4, --ipv4.

       -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
              are closed down.

              Example:
               curl --junk-session-cookies -b cookies.txt https://example.com

              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.

              Example:
               curl --keepalive-time 20 https://example.com

              See also --no-keepalive and -m, --max-time.

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

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

              Example:
               curl --key-type DER --key here https://example.com

              See also --key.

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

              If curl is built against OpenSSL library, and the engine pkcs11 is available,  then
              a  PKCS#11 URI (RFC 7512) can be used to specify a private key located in a PKCS#11
              device. A string beginning with "pkcs11:" will be interpreted as a PKCS#11 URI.  If
              a PKCS#11 URI is provided, then the --engine option will be set as "pkcs11" if none
              was provided and the --key-type option will be set as "ENG" if none was provided.

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

              Example:
               curl --cert certificate --key here https://example.com

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

       --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.

              Example:
               curl --krb clear ftp://example.com/

              See also --delegation and --ssl. --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 libcurl-us-
              ing C source code written to the file that does the equivalent of  what  your  com-
              mand-line operation does!

              This option is global and does not need to be specified for each use of -:, --next.

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

              Example:
               curl --libcurl client.c https://example.com

              See also -v, --verbose.

       --limit-rate <speed>
              Specify the maximum transfer rate you want curl to use - for both downloads and up-
              loads. This feature is useful if you have a limited pipe and you  would  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.   Append-
              ing  'k'  or 'K' will count the number as kilobytes, 'm' or 'M' makes it megabytes,
              while 'g' or 'G' makes it gigabytes. The suffixes (k, M, G, T, P) are  1024  based.
              For example 1k is 1024. Examples: 200K, 3m and 1G.

              The  rate  limiting logic works on averaging the transfer speed to no more than the
              set threshold over a period of multiple seconds.

              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.

              Examples:
               curl --limit-rate 100K https://example.com
               curl --limit-rate 1000 https://example.com
               curl --limit-rate 10M https://example.com

              See also -Y, --speed-limit and -y, --speed-time.

       -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 does not use a  standard  look  or
              format.  When  used  like this, the option causes an 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  in-
              clude sub-directories and symbolic links.

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

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

              Example:
               curl --list-only ftp://example.com/dir/

              See also -Q, --quote and -X, --request.

       --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 setting this range to something too narrow might cause un-
              necessary connection setup failures.

              Example:
               curl --local-port 1000-3000 https://example.com

              See also -g, --globoff.

       --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 will send  your  authentication  info
              (which is plaintext in the case of HTTP Basic authentication).

              Example:
               curl --location-trusted -u user:password https://example.com

              See also -u, --user.

       -L, --location
              (HTTP) If the server reports that the requested page has moved to a different loca-
              tion (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 will not be able to intercept the user+password.  See  also
              --location-trusted  on how to change this. You can limit the amount of redirects to
              follow by using the --max-redirs option.

              When curl follows a redirect and if the request is a POST, it will send the follow-
              ing  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 POST requests to GET after a 30x response by using
              the dedicated options for that: --post301, --post302 and --post303.

              The method set with -X, --request overrides the method curl would otherwise  select
              to use.

              Example:
               curl -L https://example.com

              See also --resolve and --alt-svc.

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

              You  can  use  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  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.

              Example:
               curl --login-options 'AUTH=*' imap://example.com

              See also -u, --user. 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.

              Example:
               curl --mail-auth user AT example.come -T mail smtp://example.com/

              See also --mail-rcpt and --mail-from.

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

              Example:
               curl --mail-from user AT example.com -T mail smtp://example.com/

              See also --mail-rcpt and --mail-auth.

       --mail-rcpt-allowfails
              (SMTP)  When  sending  data to multiple recipients, by default curl will abort SMTP
              conversation if at least one of the recipients causes RCPT TO command to return  an
              error.

              The  default behavior can be changed by passing --mail-rcpt-allowfails command-line
              option which will make curl ignore errors and proceed with the remaining valid  re-
              cipients.

              If  all  recipients  trigger RCPT TO failures and this flag is specified, curl will
              still abort the SMTP conversation and return the error received from  to  the  last
              RCPT TO command.

              Example:
               curl --mail-rcpt-allowfails --mail-rcpt dest AT example.com smtp://example.com

              See also --mail-rcpt. Added in 7.69.0.

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

              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 recipient should be spec-
              ified using the mailing list name, such as "Friends" or "London-Office".  (Added in
              7.34.0)

              Example:
               curl --mail-rcpt user AT example.net smtp://example.com

              See also --mail-rcpt-allowfails.

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

              Example:
               curl --manual

              See also -v, --verbose, --libcurl and --trace.

       --max-filesize <bytes>
              (FTP HTTP MQTT) 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.

              A size modifier may be used. For example, Appending 'k' or 'K' will count the  num-
              ber  as  kilobytes,  'm' or 'M' makes it megabytes, while 'g' or 'G' makes it giga-
              bytes. Examples: 200K, 3m and 1G. (Added in 7.58.0)

              NOTE: The file size is not always known prior to download, and for such files  this
              option has no effect even if the file transfer ends up being larger than this given
              limit.  Example:
               curl --max-filesize 100K https://example.com

              See also --limit-rate.

       --max-redirs <num>
              (HTTP) Set maximum number of redirections to follow. When -L, --location  is  used,
              to  prevent curl from following too many redirects, by default, the limit is set to
              50 redirects. Set this option to -1 to make it unlimited.

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

              Example:
               curl --max-redirs 3 --location https://example.com

              See also -L, --location.

       -m, --max-time <fractional seconds>
              Maximum time in seconds that you allow the whole operation to take.  This is useful
              for preventing your batch jobs from hanging for hours due to slow networks or links
              going down.  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 preci-
              sion.

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

              Examples:
               curl --max-time 10 https://example.com
               curl --max-time 2.92 https://example.com

              See also --connect-timeout.

       --metalink
              This option was previously used to specify a metalink  resource.  Metalink  support
              has been disabled in curl since 7.78.0 for security reasons.

              Example:
               curl --metalink file https://example.com

              See also -Z, --parallel.

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

              This  option  requires a library built with GSS-API or SSPI support. Use -V, --ver-
              sion 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 are not actually used.

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

              Example:
               curl --negotiate -u : https://example.com

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

       --netrc-file <filename>
              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.

              Example:
               curl --netrc-file netrc https://example.com

              See  also  -n,  --netrc,  -u,  --user  and  -K, --config. This option overrides -n,
              --netrc.

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

              Example:
               curl --netrc-optional https://example.com

              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 typically used for FTP on Unix. If  used  with
              HTTP,  curl will enable user authentication. See netrc(5) and ftp(1) for details on
              the file format. Curl will not complain if that file does not have the  right  per-
              missions (it should be neither world- nor group-readable). The environment variable
              "HOME" is used to find the home directory.

              A quick and simple example of how to setup a .netrc to allow curl to FTP to the ma-
              chine host.domain.com with user name 'myself' and password 'secret' could look sim-
              ilar to:

               machine host.domain.com
               login myself
               password secret"

              Example:
               curl --netrc https://example.com

              See also --netrc-file, -K, --config and -u, --user.

       -:, --next
              Tells curl to use a separate operation for the following  URL  and  associated  op-
              tions.  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, --verbose, --trace, --trace-ascii and --fail-early.

              For example, you can do both a GET and a POST in a single command line:

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

              Examples:
               curl https://example.com --next -d postthis www2.example.com
               curl -I https://example.com --next https://example.net/

              See also -Z, --parallel and -K, --config. 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 sup-
              ports HTTP/2 to negotiate HTTP/2 support with the server during https sessions.

              Example:
               curl --no-alpn https://example.com

              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 situations, curl will
              use a standard buffered output stream that will have the effect that it will output
              the  data in chunks, not necessarily exactly when the data arrives.  Using this op-
              tion will disable that buffering.

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

              Example:
               curl --no-buffer https://example.com

              See also -#, --progress-bar.

       --no-keepalive
              Disables  the  use  of keepalive messages on the TCP connection. curl otherwise en-
              ables them by default.

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

              Example:
               curl --no-keepalive https://example.com

              See also --keepalive-time.

       --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.

              Example:
               curl --no-npn https://example.com

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

       --no-progress-meter
              Option to switch off the progress meter output without muting or otherwise  affect-
              ing warning and informational messages like -s, --silent does.

              Note  that this is the negated option name documented. You can thus use --progress-
              meter to enable the progress meter again.

              Example:
               curl --no-progress-meter -o store https://example.com

              See also -v, --verbose and -s, --silent. Added in 7.67.0.

       --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.

              Example:
               curl --no-sessionid https://example.com

              See also -k, --insecure.

       --noproxy <no-proxy-list>
              Comma-separated list of hosts for which not to use a proxy, if  one  is  specified.
              The only wildcard is a single * character, which matches all hosts, and effectively
              disables the proxy. Each name in this list is matched as either a domain which con-
              tains  the hostname, or the hostname itself. For example, local.com would match lo-
              cal.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  ('no_proxy'  and 'NO_PROXY'). If there's an environment variable disabling a
              proxy, you can set the noproxy list to "" to override it.

              Example:
               curl --noproxy "www.example" https://example.com

              See also -x, --proxy.

       --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.

              Example:
               curl --ntlm-wb -u user:password https://example.com

              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-en-
              gineered by clever people and implemented in curl based on their efforts. This kind
              of behavior should not be endorsed, you should encourage everyone who uses NTLM  to
              switch to a public and documented authentication method instead, such as Digest.

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

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

              Example:
               curl --ntlm -u user:password https://example.com

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

       --oauth2-bearer <token>
              (IMAP POP3 SMTP HTTP) 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.

              Example:
               curl --oauth2-bearer "mF_9.B5f-4.1JqM" https://example.com

              See also --basic, --ntlm and --digest. Added in 7.33.0.

       --output-dir <dir>

              This option specifies the directory in which files should be stored, when -O, --re-
              mote-name or -o, --output are used.

              The given output directory is used for all URLs and output options on  the  command
              line, up until the first -:, --next.

              If  the  specified  target directory does not exist, the operation will fail unless
              --create-dirs is also used.

              If this option is used multiple times, the last specified directory will be used.

              Example:
               curl --output-dir "tmp" -O https://example.com

              See also -O, --remote-name and -J, --remote-header-name. Added in 7.73.0.

       -o, --output <file>
              Write output to <file> instead of stdout. If you are using {} or [] to fetch multi-
              ple documents, you should quote the URL and 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 does not 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 directories dynamically.
              Specifying the output as '-' (a single dash) will force the output to  be  done  to
              stdout.

              To suppress response bodies, you can redirect output to /dev/null:

                curl example.com -o /dev/null

              Or for Windows use nul:

                curl example.com -o nul

              Examples:
               curl -o file https://example.com
               curl "http://{one,two}.example.com" -o "file_#1.txt"
               curl "http://{site,host}.host[1-5].com" -o "#1_#2"
               curl -o file https://example.com -o file2 https://example.net

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

       --parallel-immediate
              When doing parallel transfers, this option will instruct curl that it should rather
              prefer opening up more connections in parallel at once rather than waiting  to  see
              if new transfers can be added as multiplexed streams on another connection.

              This option is global and does not need to be specified for each use of -:, --next.

              Example:
               curl --parallel-immediate -Z https://example.com -o file1 https://example.com -o file2

              See also -Z, --parallel and --parallel-max. Added in 7.68.0.

       --parallel-max <num>
              When asked to do parallel transfers, using -Z, --parallel, this option controls the
              maximum amount of transfers to do simultaneously.

              This option is global and does not need to be specified for each use of -:, --next.

              The default is 50.

              Example:
               curl --parallel-max 100 -Z https://example.com ftp://example.com/

              See also -Z, --parallel. Added in 7.66.0.

       -Z, --parallel
              Makes curl perform its transfers in parallel as compared to the regular serial man-
              ner.

              This option is global and does not need to be specified for each use of -:, --next.

              Example:
               curl --parallel https://example.com -o file1 https://example.com -o file2

              See also -:, --next and -v, --verbose. Added in 7.66.0.

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

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

              Example:
               curl --pass secret --key file https://example.com

              See also --key and -u, --user.

       --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.

              Example:
               curl --path-as-is https://example.com/../../etc/passwd

              See also --request-target. 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
              separated 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 public key provided to this option, curl will abort  the  connec-
              tion before sending or receiving any data.

              PEM/DER support:

              7.39.0: OpenSSL, GnuTLS and GSKit

              7.43.0: NSS and wolfSSL

              7.47.0: mbedtls

              sha256 support:

              7.44.0: OpenSSL, GnuTLS, NSS and wolfSSL

              7.47.0: mbedtls

              Other SSL backends not supported.

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

              Examples:
               curl --pinnedpubkey keyfile https://example.com
               curl --pinnedpubkey 'sha256//ce118b51897f4452dc' https://example.com

              See also --hostpubsha256. Added in 7.39.0.

       --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 behavior  is  ubiquitous  in
              web  browsers, so curl does the conversion by default to maintain consistency. How-
              ever, a server may require a POST to remain a POST after such a  redirection.  This
              option is meaningful only when using -L, --location.

              Example:
               curl --post301 --location -d "data" https://example.com

              See also --post302, --post303 and -L, --location.

       --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 behavior  is  ubiquitous  in
              web  browsers, so curl does the conversion by default to maintain consistency. How-
              ever, a server may require a POST to remain a POST after such a  redirection.  This
              option is meaningful only when using -L, --location.

              Example:
               curl --post302 --location -d "data" https://example.com

              See also --post301, --post303 and -L, --location.

       --post303
              (HTTP)  Tells curl to violate RFC 7231/6.4.4 and not convert POST requests into GET
              requests when following 303 redirections. A server may require a POST to  remain  a
              POST after a 303 redirection. This option is meaningful only when using -L, --loca-
              tion.

              Example:
               curl --post303 --location -d "data" https://example.com

              See also --post302, --post301 and -L, --location.

       --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:// prefix to  specify  al-
              ternative  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 characters 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.

              Example:
               curl --preproxy socks5://proxy.example -x http://http.example https://example.com

              See also -x, --proxy and --socks5. Added in 7.52.0.

       -#, --progress-bar
              Make  curl  display transfer progress as a simple progress bar instead of the stan-
              dard, 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,
              there will be space ship (-=o=-) that moves back and forth but only while  data  is
              being transferred, with a set of flying hash sign symbols on top.

              This option is global and does not need to be specified for each use of -:, --next.

              Example:
               curl -# -O https://example.com

              See also --styled-output.

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

              An unknown or unsupported protocol causes error CURLE_UNSUPPORTED_PROTOCOL (1).

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

              Without  this  option  set, curl guesses protocol based on the host name, see --url
              for details.

              Example:
               curl --proto-default https ftp.example.com

              See also --proto and --proto-redir. Added in 7.45.0.

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

              Example, allow only HTTP and HTTPS on redirect:

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

              By default curl will only allow HTTP,  HTTPS,  FTP  and  FTPS  on  redirect  (since
              7.65.2).  Specifying  all  or +all enables all protocols on redirects, which is not
              good for security.

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

              See also --proto.

       --proto <protocols>
              Tells curl to limit what protocols it may use for transfers. Protocols  are  evalu-
              ated left to right, are comma separated, and are each a protocol name or 'all', op-
              tionally prefixed by zero or more modifiers. Available modifiers are:

              +  Permit this protocol in addition to protocols already permitted (this is the de-
                 fault if no modifier is used).

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

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

              For example:

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

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

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

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

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

              Example:
               curl --proto =http,https,sftp https://example.com

              See also --proto-redir and --proto-default.

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

              Example:
               curl --proxy-anyauth --proxy-user user:passwd -x proxy https://example.com

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

       --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.

              Example:
               curl --proxy-basic --proxy-user user:passwd -x proxy https://example.com

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

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

              Example:
               curl --proxy-cacert CA-file.txt -x https://proxy https://example.com

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

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

              Example:
               curl --proxy-capath /local/directory -x https://proxy https://example.com

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

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

              Example:
               curl --proxy-cert-type PEM --proxy-cert file -x https://proxy https://example.com

              See also --proxy-cert. Added in 7.52.0.

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

              Example:
               curl --proxy-cert file -x https://proxy https://example.com

              See also --proxy-cert-type. Added in 7.52.0.

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

              Example:
               curl --proxy-ciphers ECDHE-ECDSA-AES256-CCM8 -x https://proxy https://example.com

              See also --ciphers, --curves and -x, --proxy. Added in 7.52.0.

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

              Example:
               curl --proxy-crlfile rejects.txt -x https://proxy https://example.com

              See also --crlfile and -x, --proxy. 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.

              Example:
               curl --proxy-digest --proxy-user user:passwd -x proxy https://example.com

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

       --proxy-header <header/@file>
              (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 communication only like in CONNECT requests when you want a sepa-
              rate 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.

              Starting in 7.55.0, this option can take an argument in @filename style, which then
              adds a header for each line in the input file. Using @- will  make  curl  read  the
              header file from stdin.

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

              Examples:
               curl --proxy-header "X-First-Name: Joe" -x http://proxy https://example.com
               curl --proxy-header "User-Agent: surprise" -x http://proxy https://example.com
               curl --proxy-header "Host:" -x http://proxy https://example.com

              See also -x, --proxy. Added in 7.37.0.

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

              Example:
               curl --proxy-insecure -x https://proxy https://example.com

              See also -x, --proxy and -k, --insecure. Added in 7.52.0.

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

              Example:
               curl --proxy-key-type DER --proxy-key here -x https://proxy https://example.com

              See also --proxy-key and -x, --proxy. Added in 7.52.0.

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

              Example:
               curl --proxy-key here -x https://proxy https://example.com

              See also --proxy-key-type and -x, --proxy. Added in 7.52.0.

       --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.

              Example:
               curl --proxy-negotiate --proxy-user user:passwd -x proxy https://example.com

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

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

              Example:
               curl --proxy-ntlm --proxy-user user:passwd -x http://proxy https://example.com

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

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

              Example:
               curl --proxy-pass secret --proxy-key here -x https://proxy https://example.com

              See also -x, --proxy and --proxy-key. Added in 7.52.0.

       --proxy-pinnedpubkey <hashes>
              (TLS) Tells curl to use the specified public key file (or  hashes)  to  verify  the
              proxy.  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 separated 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 public key provided to this option, curl will abort the connec-
              tion before sending or receiving any data.

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

              Examples:
               curl --proxy-pinnedpubkey keyfile https://example.com
               curl --proxy-pinnedpubkey 'sha256//ce118b51897f4452dc' https://example.com

              See also --pinnedpubkey and -x, --proxy. Added in 7.59.0.

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

              Example:
               curl --proxy-service-name "shrubbery" -x proxy https://example.com

              See also --service-name and -x, --proxy. Added in 7.43.0.

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

              Example:
               curl --proxy-ssl-allow-beast -x https://proxy https://example.com

              See also --ssl-allow-beast and -x, --proxy. Added in 7.52.0.

       --proxy-ssl-auto-client-cert
              Same as --ssl-auto-client-cert but used in HTTPS proxy context.

              Example:
               curl --proxy-ssl-auto-client-cert -x https://proxy https://example.com

              See also --ssl-auto-client-cert and -x, --proxy. Added in 7.77.0.

       --proxy-tls13-ciphers <ciphersuite list>
              (TLS) Specifies which cipher suites to use in the connection to  your  HTTPS  proxy
              when  it negotiates TLS 1.3. The list of ciphers suites must specify valid ciphers.
              Read up on TLS 1.3 cipher suite details on this URL:

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

              This option is currently used only when curl is  built  to  use  OpenSSL  1.1.1  or
              later.  If you are using a different SSL backend you can try setting TLS 1.3 cipher
              suites by using the --proxy-ciphers option.

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

              Example:
               curl --proxy-tls13-ciphers TLS_AES_128_GCM_SHA256 -x proxy https://example.com

              See also --tls13-ciphers and --curves. Added in 7.61.0.

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

              Example:
               curl --proxy-tlsauthtype SRP -x https://proxy https://example.com

              See also -x, --proxy and --proxy-tlsuser. Added in 7.52.0.

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

              Example:
               curl --proxy-tlspassword passwd -x https://proxy https://example.com

              See also -x, --proxy and --proxy-tlsuser. Added in 7.52.0.

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

              Example:
               curl --proxy-tlsuser smith -x https://proxy https://example.com

              See also -x, --proxy and --proxy-tlspassword. Added in 7.52.0.

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

              Example:
               curl --proxy-tlsv1 -x https://proxy https://example.com

              See also -x, --proxy. Added in 7.52.0.

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

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

              On systems where it works, curl will hide the given option  argument  from  process
              listings.  This  is not enough to protect credentials from possibly getting seen by
              other users on the same system as they will still be visible for  a  moment  before
              cleared. Such sensitive data should be retrieved from a file instead or similar and
              never used in clear text in a command line.

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

              Example:
               curl --proxy-user name:pwd -x proxy https://example.com

              See also --proxy-pass.

       -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 specific SOCKS version to be used.

              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 over-
              ride it.

              All operations that are performed over an HTTP proxy  will  transparently  be  con-
              verted  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, --proxytunnel option.

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

              The  proxy  host  can be specified the 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.

              Example:
               curl --proxy http://proxy.example https://example.com

              See also --socks5 and --proxy-basic.

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

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

              Example:
               curl --proxy1.0 -x http://proxy https://example.com

              See also -x, --proxy, --socks5 and --preproxy.

       -p, --proxytunnel
              When  an  HTTP proxy is used -x, --proxy, this option will make curl tunnel through
              the proxy. The tunnel approach is made with the HTTP proxy CONNECT request and  re-
              quires that the proxy allows direct connect to the remote port number curl wants to
              tunnel through to.

              To suppress proxy CONNECT response headers when curl is set to output  headers  use
              --suppress-connect-headers.

              Example:
               curl --proxytunnel -x http://proxy https://example.com

              See also -x, --proxy.

       --pubkey <key>
              (SFTP SCP) Public key file name. Allows you to provide your public key in this sep-
              arate 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  pri-
              vate  key  file,  so  passing this option is generally 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.)

              Example:
               curl --pubkey file.pub sftp://example.com/

              See also --pass.

       -Q, --quote <command>
              (FTP  SFTP)  Send an arbitrary command to the remote FTP or SFTP server. Quote com-
              mands are sent BEFORE the transfer takes place (just after the initial PWD  command
              in  an  FTP  transfer, to be exact). To make commands take place after a successful
              transfer, prefix them with a dash '-'. To make commands  be  sent  after  curl  has
              changed the working directory, just before the transfer command(s), prefix the com-
              mand with a '+' (this is only supported for FTP). You may  specify  any  number  of
              commands.

              By  default curl will stop at first failure. To make curl continue even if the com-
              mand fails, prefix the command with an asterisk (*). Otherwise, if the  server  re-
              turns 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.

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

              atime date file
                     The  atime  command  sets the last access time of the file named by the file
                     operand. The <date expression> can be all sorts of  date  strings,  see  the
                     curl_getdate(3) man page for date expression details. (Added in 7.73.0)

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

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

              chown user file
                     The chown command sets the owner of the file named by the  file  operand  to
                     the user ID specified by the user operand. The user operand is a decimal in-
                     teger user ID.

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

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

              mtime date file
                     The  mtime  command sets the last modification time of the file named by the
                     file operand. The <date expression> can be all sorts of  date  strings,  see
                     the curl_getdate(3) man page for date expression details. (Added in 7.73.0)

              pwd    The  pwd command returns the absolute pathname of the current working direc-
                     tory.

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

              rm file
                     The rm command removes the file specified by the file operand.

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

              symlink source_file target_file
                     See ln.

       Example:
        curl --quote "DELE file" ftp://example.com/foo

       See also -X, --request.

       --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.

              Example:
               curl --random-file rubbish https://example.com

              See also --egd-file.

       -r, --range <range>
              (HTTP FTP SFTP FILE) Retrieve a byte  range  (i.e.  a  partial  document)  from  an
              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  multipart  response,
              which  will  be  returned as-is by curl! Parsing or otherwise transforming this re-
              sponse is the responsibility of the caller.

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

              You should also be aware that many HTTP/1.1 servers do not have  this  feature  en-
              abled, so that when you attempt to get a range, you will instead get the whole doc-
              ument.

              FTP and SFTP range downloads only support the simple 'start-stop'  syntax  (option-
              ally  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.

              Example:
               curl --range 22-44 https://example.com

              See also -C, --continue-at and -a, --append.

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

              Example:
               curl --raw https://example.com

              See also --tr-encoding.

       -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 ap-
              pend  ";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 do not set an initial -e, --referer.

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

              Examples:
               curl --referer "https://fake.example" https://example.com
               curl --referer "https://fake.example;auto" -L https://example.com
               curl --referer ";auto" -L https://example.com

              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 does not specify 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 be loaded automat-
              ically by Windows or some third party software.

              Example:
               curl -OJ https://example.com/file

              See also -O, --remote-name.

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

              Example:
               curl --remote-name-all ftp://example.com/file1 ftp://example.com/file2

              See also -O, --remote-name.

       -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.

              Example:
               curl -O https://example.com/filename

              See also --remote-name-all.

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

              Example:
               curl --remote-time -o foo https://example.com

              See also -O, --remote-name and -z, --time-cond.

       --request-target <path>
              (HTTP)  Tells  curl to use an alternative "target" (path) instead of using the path
              as provided in the URL. Particularly useful when wanting  to  issue  HTTP  requests
              without  leading  slash or other data that does not follow the regular URL pattern,
              like "OPTIONS *".

              Example:
               curl --request-target "*" -X OPTIONS https://example.com

              See also -X, --request. Added in 7.55.0.

       -X, --request <method>
              (HTTP) Specifies a custom request method to use when communicating  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  ex-
              planations.  Common  additional  HTTP  requests include PUT and DELETE, but related
              technologies like WebDAV offers PROPFIND, COPY, MOVE and more.

              Normally you do not need this option. All sorts of GET, HEAD, POST and PUT requests
              are rather invoked by using dedicated command line options.

              This  option only changes the actual word used in the HTTP request, it does not al-
              ter 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
              does not change request method according to the HTTP 30x response codes - and simi-
              lar.

              (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.

              (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.

              Examples:
               curl -X "DELETE" https://example.com
               curl -X NLST ftp://example.com/

              See also --request-target.

       --resolve <[+]host:port:addr[,addr]...>
              Provide a custom address for a specific host and port pair.  Using  this,  you  can
              make  the  curl  requests(s) use a specified address and prevent the otherwise nor-
              mally resolved address to be used. Consider it a  sort  of  /etc/hosts  alternative
              provided  on  the  command  line. The port number should be the number used for the
              specific protocol the host will be used for. It means you need several  entries  if
              you want to provide address for the same host but different ports.

              By  specifying  '*' as host you can tell curl to resolve any host and specific port
              pair to the specified address. Wildcard is resolved last so any  --resolve  with  a
              specific host and port will be used first.

              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.

              By prefixing the host with a '+' you can make the entry time out after  curl's  de-
              fault timeout (1 minute). Note that this will only make sense for long running par-
              allel transfers with a lot of files. In such cases, if this  option  is  used  curl
              will try to resolve the host as it normally would once the timeout has expired.

              Support for providing the IP address within [brackets] was added in 7.57.0.

              Support for providing multiple IP addresses per entry was added in 7.59.0.

              Support for resolving with wildcard was added in 7.64.0.

              Support for the '+' prefix was was added in 7.75.0.

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

              Example:
               curl --resolve example.com:443:127.0.0.1 https://example.com

              See also --connect-to and --alt-svc.

       --retry-all-errors
              Retry on any error. This option is used together with --retry.

              This  option  is  the "sledgehammer" of retrying. Do not use this option by default
              (eg in curlrc), there may be unintended consequences such as sending  or  receiving
              duplicate  data.  Do  not use with redirected input or output. You'd be much better
              off handling your unique problems in shell script. Please read the example below.

              WARNING: For server compatibility curl attempts to retry failed flaky transfers  as
              close  as  possible  to  how they were started, but this is not possible with redi-
              rected input or output. For example, before retrying it removes output data from  a
              failed  partial  transfer  that  was written to an output file. However this is not
              true of data redirected to a | pipe or > file, which are  not  reset.  We  strongly
              suggest you do not parse or record output via redirect in combination with this op-
              tion, since you may receive duplicate data.

              By default curl will not error on an HTTP response code that indicates an HTTP  er-
              ror, if the transfer was successful. For example, if a server replies 404 Not Found
              and the reply is fully received then that is not an error.  When  --retry  is  used
              then  curl  will retry on some HTTP response codes that indicate transient HTTP er-
              rors, but that does not include most 4xx response codes such as 404. If you want to
              retry  on  all  response codes that indicate HTTP errors (4xx and 5xx) then combine
              with -f, --fail.

              Example:
               curl --retry 5 --retry-all-errors https://example.com

              See also --retry. Added in 7.71.0.

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

              Example:
               curl --retry-connrefused --retry https://example.com

              See also --retry and --retry-all-errors. 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  re-
              tries). 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.

              Example:
               curl --retry-delay 5 --retry https://example.com

              See also --retry.

       --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 has not reached this given limit. Notice
              that if the timer has not reached the limit, the request will  be  made  and  while
              performing,  it  may take longer than this given time period. To limit a single re-
              quest'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.

              Example:
               curl --retry-max-time 30 --retry 10 https://example.com

              See also --retry.

       --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 408, 429, 500, 502, 503 or 504 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-de-
              lay  you  disable  this exponential backoff algorithm. See also --retry-max-time to
              limit the total time allowed for retries.

              Since curl 7.66.0, curl will comply with the Retry-After: response  header  if  one
              was present to know when to issue the next retry.

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

              Example:
               curl --retry 7 https://example.com

              See also --retry-max-time.

       --sasl-authzid <identity>
              Use this authorisation identity (authzid), during SASL PLAIN authentication, in ad-
              dition to the authentication identity (authcid) as specified by -u, --user.

              If the option is not specified, the server will derive the authzid from  the  auth-
              cid,  but  if specified, and depending on the server implementation, it may be used
              to access another user's inbox, that the user has been  granted  access  to,  or  a
              shared mailbox for example.

              Example:
               curl --sasl-authzid zid imap://example.com/

              See also --login-options. Added in 7.66.0.

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

              Example:
               curl --sasl-ir imap://example.com/

              See also --sasl-authzid. 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.

              Example:
               curl --service-name sockd/server https://example.com

              See also --negotiate and --proxy-service-name. Added in 7.43.0.

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

              This option is global and does not need to be specified for each use of -:, --next.

              Example:
               curl --show-error --silent https://example.com

              See also --no-progress-meter.

       -s, --silent
              Silent  or  quiet  mode.  Do  not show progress meter or error messages. Makes Curl
              mute. It will still output the data you ask for, potentially  even  to  the  termi-
              nal/stdout unless you redirect it.

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

              Example:
               curl -s https://example.com

              See also -v, --verbose, --stderr and --no-progress-meter.

       --socks4 <host[:port]>
              Use the specified SOCKS4 proxy. If the port number is not specified, it is  assumed
              at  port  1080.  Using this socket type make curl resolve the host name and passing
              the address on to the proxy.

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

              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 connects (through SOCKS) to the HTTP or HTTPS proxy.

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

              Example:
               curl --socks4 hostname:4096 https://example.com

              See also --socks4a, --socks5 and --socks5-hostname.

       --socks4a <host[:port]>
              Use the specified SOCKS4a proxy. If the port number is not specified, it is assumed
              at port 1080. This asks the proxy to resolve the host name.

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

              This option is superfluous since you can specify a socks4a proxy with  -x,  --proxy
              using a socks4a:// 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 connects (through SOCKS) to the HTTP or HTTPS proxy.

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

              Example:
               curl --socks4a hostname:4096 https://example.com

              See also --socks4, --socks5 and --socks5-hostname.

       --socks5-basic
              Tells  curl  to  use  username/password  authentication when connecting to a SOCKS5
              proxy.   The  username/password  authentication  is  enabled   by   default.    Use
              --socks5-gssapi to force GSS-API authentication to SOCKS5 proxies.

              Example:
               curl --socks5-basic --socks5 hostname:4096 https://example.com

              See also --socks5. Added in 7.55.0.

       --socks5-gssapi-nec
              As  part  of the GSS-API negotiation a protection mode is negotiated. RFC 1961 says
              in section 4.3/4.4 it should be protected, but  the  NEC  reference  implementation
              does  not.  The  option  --socks5-gssapi-nec allows the unprotected exchange of the
              protection mode negotiation.

              Example:
               curl --socks5-gssapi-nec --socks5 hostname:4096 https://example.com

              See also --socks5.

       --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.

              Example:
               curl --socks5-gssapi-service sockd --socks5 hostname:4096 https://example.com

              See also --socks5.

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

              Example:
               curl --socks5-gssapi --socks5 hostname:4096 https://example.com

              See also --socks5. Added in 7.55.0.

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

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

              This option is superfluous since you can specify a socks5 hostname proxy  with  -x,
              --proxy using a socks5h:// 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 connects (through SOCKS) to the HTTP or HTTPS proxy.

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

              Example:
               curl --socks5-hostname proxy.example:7000 https://example.com

              See also --socks5 and --socks4a.

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

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

              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 connects (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.

              Example:
               curl --socks5 proxy.example:7000 https://example.com

              See also --socks5-hostname and --socks4a.

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

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

              Example:
               curl --speed-limit 300 --speed-time 10 https://example.com

              See also -y, --speed-time, --limit-rate and -m, --max-time.

       -y, --speed-time <seconds>
              If a download is slower than speed-limit bytes per second during a  speed-time  pe-
              riod,  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.

              Example:
               curl --speed-limit 300 --speed-time 10 https://example.com

              See also -Y, --speed-limit and --limit-rate.

       --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 is not used, the SSL layer may use  work-
              arounds  known  to  cause interoperability problems with some older SSL implementa-
              tions.

              WARNING: this option loosens the SSL security, and by using this flag you  ask  for
              exactly that.

              Example:
               curl --ssl-allow-beast https://example.com

              See also --proxy-ssl-allow-beast and -k, --insecure.

       --ssl-auto-client-cert
              Tell  libcurl  to automatically locate and use a client certificate for authentica-
              tion, when requested by the server. This option is only supported for Schannel (the
              native  Windows  SSL  library).  Prior  to  7.77.0 this was the default behavior in
              libcurl with Schannel. Since the server can request any certificate  that  supports
              client  authentication  in the OS certificate store it could be a privacy violation
              and unexpected.

              Example:
               curl --ssl-auto-client-cert https://example.com

              See also --proxy-ssl-auto-client-cert. Added in 7.77.0.

       --ssl-no-revoke
              (Schannel) This option tells curl to disable certificate revocation checks.   WARN-
              ING:  this  option loosens the SSL security, and by using this flag you ask for ex-
              actly that.

              Example:
               curl --ssl-no-revoke https://example.com

              See also --crlfile. Added in 7.44.0.

       --ssl-reqd
              (FTP IMAP POP3 SMTP LDAP) Require SSL/TLS for the connection. Terminates  the  con-
              nection if the server does not support SSL/TLS.

              This  option  is handled in LDAP since version 7.81.0. It is fully supported by the
              openldap backend and rejected by the generic ldap backend if explicit  TLS  is  re-
              quired.

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

              Example:
               curl --ssl-reqd ftp://example.com

              See also --ssl and -k, --insecure.

       --ssl-revoke-best-effort
              (Schannel) This option tells curl to ignore certificate revocation checks when they
              failed due to missing/offline distribution points for the revocation check lists.

              Example:
               curl --ssl-revoke-best-effort https://example.com

              See also --crlfile and -k, --insecure. Added in 7.70.0.

       --ssl  (FTP IMAP POP3 SMTP LDAP) Try to use SSL/TLS for the connection. Reverts to a  non-
              secure  connection  if the server does not support SSL/TLS. See also --ftp-ssl-con-
              trol and --ssl-reqd for different levels of encryption required.

              This option is handled in LDAP since version 7.81.0. It is fully supported  by  the
              openldap backend and ignored by the generic ldap backend.

              Please note that a server may close the connection if the negotiation does not suc-
              ceed.

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

              Example:
               curl --ssl pop3://example.com/

              See also -k, --insecure and --ciphers.

       -2, --sslv2
              (SSL)  This  option previously asked curl to use SSLv2, but starting in curl 7.77.0
              this instruction is ignored. SSLv2 is widely considered insecure (see RFC 6176).

              Example:
               curl --sslv2 https://example.com

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

       -3, --sslv3
              (SSL) This option previously asked curl to use SSLv3, but starting in  curl  7.77.0
              this instruction is ignored. SSLv3 is widely considered insecure (see RFC 7568).

              Example:
               curl --sslv3 https://example.com

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

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

              This option is global and does not need to be specified for each use of -:, --next.

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

              Example:
               curl --stderr output.txt https://example.com

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

       --styled-output
              Enables the automatic use of bold font styles when writing HTTP headers to the ter-
              minal. Use --no-styled-output to switch them off.

              This option is global and does not need to be specified for each use of -:, --next.

              Example:
               curl --styled-output -I https://example.com

              See also -I, --head and -v, --verbose. Added in 7.61.0.

       --suppress-connect-headers
              When  -p,  --proxytunnel  is used and a CONNECT request is made do not output proxy
              CONNECT response headers. This option is meant to be used with -D, --dump-header or
              -i,  --include which are used to show protocol headers in the output. It has no ef-
              fect on debug options such as -v, --verbose or --trace, or any statistics.

              Example:
               curl --suppress-connect-headers --include -x proxy https://example.com

              See also -D, --dump-header, -i, --include and -p, --proxytunnel. Added in 7.54.0.

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

              Example:
               curl --tcp-fastopen https://example.com

              See also --false-start. 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 explicitly switch it
              off if you do not want it on.

              Example:
               curl --tcp-nodelay https://example.com

              See also -N, --no-buffer.

       -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.

              Example:
               curl -t TTYPE=vt100 telnet://example.com/

              See also -K, --config.

       --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.

              Example:
               curl --tftp-blksize 1024 tftp://example.com/file

              See also --tftp-no-options.

       --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 ig-
              nored.

              Example:
               curl --tftp-no-options tftp://192.168.0.1/

              See also --tftp-blksize. 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 does not 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 speci-
              fied date/time.

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

              Examples:
               curl -z "Wed 01 Sep 2021 12:18:00" https://example.com
               curl -z "-Wed 01 Sep 2021 12:18:00" https://example.com
               curl -z file https://example.com

              See also --etag-compare and -R, --remote-time.

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

              If  the  connection  is  done without TLS, this option has no effect. This includes
              QUIC-using (HTTP/3) transfers.

              default
                     Use up to recommended TLS version.

              1.0    Use up to TLSv1.0.

              1.1    Use up to TLSv1.1.

              1.2    Use up to TLSv1.2.

              1.3    Use up to TLSv1.3.

       Examples:
        curl --tls-max 1.2 https://example.com
        curl --tls-max 1.3 --tlsv1.2 https://example.com

       See also --tlsv1.0, --tlsv1.1, --tlsv1.2 and --tlsv1.3. --tls-max requires that the under-
       lying libcurl was built to support TLS. Added in 7.54.0.

       --tls13-ciphers <ciphersuite list>
              (TLS)  Specifies  which cipher suites to use in the connection if it negotiates TLS
              1.3. The list of ciphers suites must specify valid ciphers. Read up on TLS 1.3  ci-
              pher suite details on this URL:

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

              This  option  is  currently  used  only  when curl is built to use OpenSSL 1.1.1 or
              later. If you are using a different SSL backend you can try setting TLS 1.3  cipher
              suites by using the --ciphers option.

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

              Example:
               curl --tls13-ciphers TLS_AES_128_GCM_SHA256 https://example.com

              See also --ciphers and --curves. Added in 7.61.0.

       --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". This option works only if the underly-
              ing libcurl is built with TLS-SRP support, which requires OpenSSL  or  GnuTLS  with
              TLS-SRP support.

              Example:
               curl --tlsauthtype SRP https://example.com

              See also --tlsuser.

       --tlspassword <string>
              Set  password  for  use  with  the  TLS  authentication method specified with --tl-
              sauthtype. Requires that --tlsuser also be set.

              This option does not work with TLS 1.3.

              Example:
               curl --tlspassword pwd --tlsuser user https://example.com

              See also --tlsuser.

       --tlsuser <name>
              Set username for use with  the  TLS  authentication  method  specified  with  --tl-
              sauthtype. Requires that --tlspassword also is set.

              This option does not work with TLS 1.3.

              Example:
               curl --tlspassword pwd --tlsuser user https://example.com

              See also --tlspassword.

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

              In old versions of curl this option was documented to allow _only_ TLS  1.0.   That
              behavior  was  inconsistent depending on the TLS library. Use --tls-max if you want
              to set a maximum TLS version.

              Example:
               curl --tlsv1.0 https://example.com

              See also --tlsv1.3. Added in 7.34.0.

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

              In  old  versions of curl this option was documented to allow _only_ TLS 1.1.  That
              behavior was inconsistent depending on the TLS library. Use --tls-max if  you  want
              to set a maximum TLS version.

              Example:
               curl --tlsv1.1 https://example.com

              See also --tlsv1.3. Added in 7.34.0.

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

              In old versions of curl this option was documented to allow _only_ TLS  1.2.   That
              behavior  was  inconsistent depending on the TLS library. Use --tls-max if you want
              to set a maximum TLS version.

              Example:
               curl --tlsv1.2 https://example.com

              See also --tlsv1.3. Added in 7.34.0.

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

              If  the  connection  is  done without TLS, this option has no effect. This includes
              QUIC-using (HTTP/3) transfers.

              Note that TLS 1.3 is not supported by all TLS backends.

              Example:
               curl --tlsv1.3 https://example.com

              See also --tlsv1.2. Added in 7.52.0.

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

              Example:
               curl --tlsv1 https://example.com

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

              Example:
               curl --tr-encoding https://example.com

              See also --compressed.

       --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 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 un-
              trained humans.

              This option is global and does not need to be specified for each use of -:, --next.

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

              Example:
               curl --trace-ascii log.txt https://example.com

              See also -v, --verbose and --trace. This option overrides --trace  and  -v,  --ver-
              bose.

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

              This option is global and does not need to be specified for each use of -:, --next.

              Example:
               curl --trace-time --trace-ascii output https://example.com

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

       --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.

              This option is global and does not need to be specified for each use of -:, --next.

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

              Example:
               curl --trace log.txt https://example.com

              See  also  --trace-ascii  and --trace-time. This option overrides -v, --verbose and
              --trace-ascii.

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

              Example:
               curl --unix-socket socket-path https://example.com

              See also --abstract-unix-socket. 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.  Alter-
              nately, the file name "." (a single period) may be specified instead of "-" to  use
              stdin  in non-blocking mode to allow reading server output while stdin is being up-
              loaded.

              You can specify one -T, --upload-file for each URL on the command  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 supported in the URL.

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

              Examples:
               curl -T file https://example.com
               curl -T "img[1-1000].png" ftp://ftp.example.com/
               curl --upload-file "{file1,file2}" https://example.com

              See also -G, --get and -I, --head.

       --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.

              WARNING:  On  Windows,  particular file:// accesses can be converted to network ac-
              cesses by the operating system. Beware!

              Example:
               curl --url https://example.com

              See also -:, --next and -K, --config.

       -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.

              Example:
               curl -B ftp://example.com/README

              See also --crlf and --data-ascii.

       -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 header can also be
              set with the -H, --header or the --proxy-header options.

              If you give an empty argument to -A, --user-agent (""), it will remove  the  header
              completely from the request. If you prefer a blank header, you can set it to a sin-
              gle space (" ").

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

              Example:
               curl -A "Agent 007" https://example.com

              See also -H, --header and --proxy-header.

       -u, --user <user:password>
              Specify the user name and password to use for server authentication. 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 impos-
              sible to use a colon in the user name with this option. The password can, still.

              On systems where it works, curl will hide the given option  argument  from  process
              listings.  This  is not enough to protect credentials from possibly getting seen by
              other users on the same system as they will still be visible for  a  moment  before
              cleared. Such sensitive data should be retrieved from a file instead or similar and
              never used in clear text in a command line.

              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 Ker-
              beros Ticket. If you do not, 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 AT example.com respectively.

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

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

              Example:
               curl -u user:secret https://example.com

              See also -n, --netrc and -K, --config.

       -v, --verbose
              Makes curl verbose during the operation. Useful for debugging and seeing what's go-
              ing 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
              are looking for.

              If  you  think  this  option still does not give you enough details, consider using
              --trace or --trace-ascii instead.

              This option is global and does not need to be specified for each use of -:, --next.

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

              Example:
               curl --verbose https://example.com

              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  li-
              braries 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:

              alt-svc
                     Support for the Alt-Svc: header is provided.

              AsynchDNS
                     This curl uses asynchronous name resolves. Asynchronous name resolves can be
                     done using either the c-ares or the threaded resolver backends.

              brotli Support for automatic brotli compression over HTTP(S).

              CharConv
                     curl was built with support for character set conversions (like EBCDIC)

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

              gsasl  The  built-in  SASL  authentication includes extensions to support SCRAM be-
                     cause libcurl was built with libgsasl.

              GSS-API
                     GSS-API is supported.

              HSTS   HSTS support is present.

              HTTP2  HTTP/2 support has been built-in.

              HTTP3  HTTP/3 support has been built-in.

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

              IDN    This curl supports IDN - international domain names.

              IPv6   You can use IPv6 with this.

              Kerberos
                     Kerberos V5 authentication is supported.

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

              libz   Automatic decompression (via gzip, deflate) of compressed files over HTTP is
                     supported.

              MultiSSL
                     This curl supports multiple TLS backends.

              NTLM   NTLM authentication is supported.

              NTLM_WB
                     NTLM delegation to winbind helper is supported.

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

              SPNEGO SPNEGO authentication is supported.

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

              SSPI   SSPI is supported.

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

              TrackMemory
                     Debug memory tracking is supported.

              Unicode
                     Unicode support on Windows.

              UnixSockets
                     Unix sockets support is provided.

              zstd   Automatic  decompression  (via  zstd)  of compressed files over HTTP is sup-
                     ported.

       Example:
        curl --version

       See also -h, --help and -M, --manual.

       -w, --write-out <format>
              Make curl display information on stdout after a completed transfer. 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 %{vari-
              able_name} and to output a normal % you just write them as %%.  You  can  output  a
              newline by using \n, a carriage return with \r and a tab space with \t.

              The output will be written to standard output, but this can be switched to standard
              error by using %{stderr}.

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

              The variables available are:

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

              errormsg       The error message. (Added in 7.75.0)

              exitcode       The numerical exitcode of the transfer. (Added in 7.75.0)

              filename_effective
                             The ultimate filename that curl writes out to. This is only meaning-
                             ful 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.

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

              http_code      The  numerical  response  code  that was found in the last retrieved
                             HTTP(S) or FTP(s) transfer.

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

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

              json           A JSON object with all available keys.

              local_ip       The IP address of the local end of the most recently done connection
                             - can be either IPv4 or IPv6.

              local_port     The local port number of the most recently done connection.

              method         The http method used in the most  recent  HTTP  request.  (Added  in
                             7.72.0)

              num_connects   Number of new connects made in the recent transfer.

              num_headers    The number of response headers in the most recent request (restarted
                             at each
                              redirect). Note that the status line IS NOT a header. (Added in 7.73.0)

              num_redirects  Number of redirects that were followed in the request.

              onerror        The rest of the output is only shown if the transfer returned a non-
                             zero error (Added in 7.75.0)

              proxy_ssl_verify_result
                             The  result  of  the HTTPS proxy's SSL peer certificate 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, --location to follow redi-
                             rects (or when --max-redirs is met), this variable will show the ac-
                             tual URL a redirect would have gone to.

              referer        The Referer: header, if there was any. (Added in 7.76.0)

              remote_ip      The  remote IP address of the most recently done connection - can be
                             either IPv4 or IPv6.

              remote_port    The remote port number of the most recently done connection.

              response_code  The numerical response code that was  found  in  the  last  transfer
                             (formerly known as "http_code").

              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. This is the size  of
                             the body/data that was transferred, excluding headers.

              size_header    The total amount of bytes of the downloaded headers.

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

              size_upload    The  total  amount  of bytes that were uploaded. This is the size of
                             the body/data that was transferred, excluding headers.

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

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

              ssl_verify_result
                             The result of the SSL peer certificate  verification  that  was  re-
                             quested. 0 means the verification was successful.

              stderr         From  this  point  on, the -w, --write-out output will be written to
                             standard error. (Added in 7.63.0)

              stdout         From this point on, the -w, --write-out output will  be  written  to
                             standard  output.   This  is  the default, but can be used to switch
                             back after switching to stderr.  (Added in 7.63.0)

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

              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  resolv-
                             ing 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
                             negotiations  that  are  specific  to the particular protocol(s) in-
                             volved.

              time_redirect  The time, in seconds, it took for all  redirection  steps  including
                             name  lookup,  connect,  pretransfer  and  transfer before the final
                             transaction was started. time_redirect shows the complete  execution
                             time for multiple redirections.

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

              time_total     The total time, in seconds, that the full operation lasted.

              url            The URL that was fetched. (Added in 7.75.0)

              urlnum         The  URL  index  number of this transfer, 0-indexed. De-globbed URLs
                             share the same index number as the origin  globbed  URL.  (Added  in
                             7.75.0)

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

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

              Example:
               curl -w '%{http_code}\n' https://example.com

              See also -v, --verbose and -I, --head.

       --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 at-
              tribute 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.

              Example:
               curl --xattr -o storage https://example.com

              See also -R, --remote-time, -w, --write-out and -v, --verbose.

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 protocol 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/domains>
              list  of host names that should not go through any proxy. If set to an asterisk '*'
              only, it matches all hosts. Each name in this list is matched as  either  a  domain
              name which contains the hostname, or the hostname itself.

              This  environment  variable  disables use of the proxy even when specified with the
              -x, --proxy option. That is NO_PROXY=direct.example.com curl -x  http://proxy.exam-
              ple.com   http://direct.example.com   accesses   the   target   URL  directly,  and
              NO_PROXY=direct.example.com curl -x http://proxy.example.com http://somewhere.exam-
              ple.com accesses the target URL through the proxy.

              The  list  of  host names can also be include numerical IP addresses, and IPv6 ver-
              sions should then be given without enclosing brackets.

              IPv6 numerical addresses are compared as strings, so they will only  match  if  the
              representations are the same: "::1" is the same as "::0:1" but they do not match.

       APPDATA <dir>
              On  Windows,  this  variable is used when trying to find the home directory. If the
              primary home variable are all unset.

       COLUMNS <terminal width>
              If set, the specified number of characters will be used as the terminal width  when
              the  alternative  progress-bar is shown. If not set, curl will try to figure it out
              using other ways.

       CURL_CA_BUNDLE <file>
              If set, will be used as the --cacert value.

       CURL_HOME <dir>
              If set, is the first variable curl checks when trying to find its  home  directory.
              If not set, it continues to check XDG_CONFIG_HOME.

       CURL_SSL_BACKEND <TLS backend>
              If curl was built with support for "MultiSSL", meaning that it has built-in support
              for more than one TLS backend, this environment variable can be set to the case in-
              sensitive  name  of  the  particular backend to use when curl is invoked. Setting a
              name that is not a built-in alternative will make curl stay with the default.

              SSL backend names (case-insensitive): bearssl, gnutls,  gskit,  mbedtls,  mesalink,
              nss, openssl, rustls, schannel, secure-transport, wolfssl

       HOME <dir>
              If  set,  this  is  used  to find the home directory when that is needed. Like when
              looking for the default .curlrc. CURL_HOME and XDG_CONFIG_HOME have preference.

       QLOGDIR <directory name>
              If curl was built with HTTP/3 support, setting this environment variable to a local
              directory  will  make  curl produce qlogs in that directory, using file names named
              after the destination connection id (in hex). Do note that these files  can  become
              rather large. Works with both QUIC backends.

       SHELL  Used on VMS when trying to detect if using a DCL or a "unix" shell.

       SSL_CERT_DIR <dir>
              If set, will be used as the --capath value.

       SSL_CERT_FILE <path>
              If set, will be used as the --cacert value.

       SSLKEYLOGFILE <file name>
              If  you  set  this environment variable to a file name, curl will store TLS secrets
              from its connections in that file when invoked to enable you  to  analyze  the  TLS
              traffic  in  real  time using network analyzing tools such as Wireshark. This works
              with the following TLS backends: OpenSSL,  libressl,  BoringSSL,  GnuTLS,  NSS  and
              wolfSSL.

       USERPROFILE <dir>
              On  Windows,  this  variable is used when trying to find the home directory. If the
              other, primary, variable are all unset. If set, curl will use the  path  "$USERPRO-
              FILE\Application Data".

       XDG_CONFIG_HOME <dir>
              If  CURL_HOME  is  not  set,  this  variable  is checked when looking for a default
              .curlrc file.

PROXY PROTOCOL PREFIXES
       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 does not match a sup-
       ported one, the proxy will be treated as an HTTP proxy.

       The supported proxy protocol prefixes are as follows:

       http://
              Makes it use it as an HTTP proxy. The default if no scheme prefix is used.

       https://
              Makes it treated as an HTTPS proxy.

       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 under error conditions. At the time of this writing, the exit codes are:

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

       2      Failed to initialize.

       3      URL malformed. The syntax was not correct.

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

       5      Could not resolve proxy. The given proxy host could not be resolved.

       6      Could not resolve host. The given remote host could not be resolved.

       7      Failed to connect to host.

       8      Weird server reply. The server sent data curl could not parse.

       9      FTP  access  denied. The server denied login or denied access to the particular re-
              source or directory you wanted to reach. Most often you tried to change to a direc-
              tory that does not 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 could not 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 could not parse the reply sent to the PASV request.

       14     FTP weird 227 format. Curl could not parse the 227-line the server sent.

       15     FTP cannot use host. Could not 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 could not set binary. Could not change transfer method to binary.

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

       19     FTP could not download/access the given file, the RETR (or similar) command failed.

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

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

       23     Write error. Curl could not write data to a local filesystem or similar.

       25     FTP could not STOR file. The server denied the STOR operation, used for FTP upload-
              ing.

       26     Read error. Various reading problems.

       27     Out of memory. A memory allocation request failed.

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

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

       31     FTP  could  not use REST. The REST command failed. This command is used for resumed
              FTP transfers.

       33     HTTP range error. The range "command" did not work.

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

       35     SSL connect error. The SSL handshaking failed.

       36     Bad download resume. Could not continue an earlier aborted download.

       37     FILE could not read file. Failed to open the file. Permissions?

       38     LDAP cannot bind. LDAP bind operation failed.

       39     LDAP search failed.

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

       42     Aborted by callback. An application told curl to abort the operation.

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

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

       47     Too many redirects. When following redirects, curl hit the maximum amount.

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

       49     Malformed telnet option.

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

       52     The server did not 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     Could not use specified SSL cipher.

       60     Peer certificate cannot be authenticated with known CA certificates.

       61     Unrecognized transfer encoding.

       62     Invalid LDAP URL.

       63     Maximum file size exceeded.

       64     Requested FTP SSL level failed.

       65     Sending the data requires a rewind that failed.

       66     Failed to initialise SSL Engine.

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

       68     File not found on TFTP server.

       69     Permission problem on TFTP server.

       70     Out of disk space on TFTP server.

       71     Illegal TFTP operation.

       72     Unknown TFTP transfer ID.

       73     File already exists (TFTP).

       74     No such user (TFTP).

       75     Character conversion failed.

       76     Character conversion functions required.

       77     Problem 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.

       83     Issuer check failed.

       84     The FTP PRET command failed.

       85     Mismatch of RTSP CSeq numbers.

       86     Mismatch of RTSP 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.

       91     Invalid SSL certificate status.

       92     Stream error in HTTP/2 framing layer.

       93     An API function was called from inside a callback.

       94     An authentication function returned an error.

       95     A problem was detected in the HTTP/3 layer. This is somewhat generic and can be one
              out of several problems, see the error message for details.

       96     QUIC connection error. This error may be caused by an SSL library  error.  QUIC  is
              the protocol used for HTTP/3 transfers.

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

BUGS
       If you experience any problems with curl, submit an issue in the project's bug tracker  on
       GitHub: https://github.com/curl/curl/issues

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

WWW
       https://curl.se

SEE ALSO
       ftp(1), wget(1)

curl 7.81.0                              January 03 2022                                  curl(1)

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