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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 using URLs. 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, TFTP, WS and WSS.

       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.

       If you provide a URL without a leading protocol:// scheme, curl guesses
       what  protocol  you  want.  It then defaults to HTTP but assumes others
       based on often-used host name prefixes. For  example,  for  host  names
       starting with "ftp." curl assumes you want FTP.

       You  can  specify  any  amount  of  URLs  on the command line. They are
       fetched in a sequential manner in the specified order  unless  you  use
       -Z, --parallel. You can specify command line options and URLs mixed and
       in any order on the command line.

       curl attempts to reuse connections when doing  multiple  transfers,  so
       that  getting  many files from the same server do not use multiple con-
       nects and setup handshakes. This improves speed. Connection  reuse  can
       only  be  done  for URLs specified for a single command line invocation
       and cannot be performed between separate curl runs.

       Provide an IPv6 zone id in the URL with  an  escaped  percentage  sign.
       Like in

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

       Everything  provided  on  the  command  line that is not a command line
       option or its argument, curl assumes is a URL and treats it as such.

GLOBBING
       You can specify multiple URLs or parts of URLs by writing lists  within
       braces or ranges within brackets. We call this "globbing".

       Provide a list with three different names like this:

         "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 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 '*'.

       Switch off globbing with -g, --globoff.

VARIABLES
       curl supports command line variables (added in  8.3.0).  Set  variables
       with  --variable name=content or --variable name@file (where "file" can
       be stdin if set to a single dash (-)).

       Variable contents can expanded in option  parameters  using  "{{name}}"
       (without  the  quotes) if the option name is prefixed with "--expand-".
       This gets the contents of the variable "name" inserted, or a  blank  if
       the  name  does  not  exist  as a variable. Insert "{{" verbatim in the
       string by prefixing it with a backslash, like "\{{".

       You an access and expand environment variables by first importing them.
       You  can select to either require the environment variable to be set or
       you can provide a default value in case it is not  already  set.  Plain
       --variable  %name  imports the variable called 'name' but exits with an
       error if that environment variable is not already  set.  To  provide  a
       default value if it is not set, use --variable %name=content or --vari-
       able %name@content.

       Example. Get the USER environment variable into the URL, fail  if  USER
       is not set:

        --variable '%USER'
        --expand-url = "https://example.com/api/{{USER}}/method"

       When  expanding  variables,  curl  supports a set of functions that can
       make the variable contents more convenient to use. It can trim  leading
       and  trailing  white  space  with trim, it can output the contents as a
       JSON quoted string with json, URL encode the string with url or  base64
       encode  it  with  b64.  You apply function to a variable expansion, add
       them colon separated to the right side of the variable.  Variable  con-
       tent holding null bytes that are not encoded when expanded cause error.

       Example:  get  the contents of a file called $HOME/.secret into a vari-
       able called "fix". Make sure that  the  content  is  trimmed  and  per-
       cent-encoded sent as POST data:

         --variable %HOME
         --expand-variable fix@{{HOME}}/.secret
         --expand-data "{{fix:trim:url}}"
         https://example.com/

       Command line variables and expansions were added in in 8.3.0.

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 options. 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 options.

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 works.

       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 options.

       IMAP(S)
              Using  the mail reading protocol, curl can "download" emails for
              you. With or without 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 "sub-
              scribe" 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 serve
              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 transferred data,  transfer  speeds  and  estimated  time
       left,  etc.  The progress meter displays the transfer rate in bytes per
       second. The suffixes (k, M, G, T, P) are 1024 based. For example 1k  is
       1024 bytes. 1M is 1048576 bytes.

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

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

       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.

VERSION
       This man page describes curl 8.4.0. If you use a later version, chances
       are this man page does not fully document it. If  you  use  an  earlier
       version, this document tries to include version information about which
       specific version that introduced changes.

       You can always learn which the latest curl version is by running

         curl https://curl.se/info

       The online version of this man page is always showing the latest incar-
       nation: https://curl.se/docs/manpage.html

OPTIONS
       Options  start  with  one or two dashes. Many of the options require an
       additional value next to them. If provided text does not start  with  a
       dash, it is presumed to be and treated as a URL.

       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.

       When -:, --next is used, it resets the parser state and you start again
       with a clean option state, except for the options  that  are  "global".
       Global options retain their values and meaning even after -:, --next.

       The  following  options  are  global: --fail-early, --libcurl, --paral-
       lel-immediate,  -Z,  --parallel,  -#,   --progress-bar,   --rate,   -S,
       --show-error, --stderr, --styled-output, --trace-ascii, --trace-config,
       --trace-ids, --trace-time, --trace and -v, --verbose.

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

              If  --abstract-unix-socket  is  provided several times, the last
              set value is used.

              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 gets
              used. After a completed transfer, the cache is 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 loads  contents  from
              all the files but the last one is used for saving.

              --alt-svc can be used several times in a command line

              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 authenti-
              cation method, which you can do with --basic, --digest,  --ntlm,
              and --negotiate.

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

              Used together with -u, --user.

              Providing --anyauth multiple times has no extra effect.

              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 option makes curl append
              to the target file instead of overwriting it. If the remote file
              does not exist, it is created. Note that this flag is ignored by
              some SFTP servers (including OpenSSH).

              Providing -a, --append multiple times has no extra effect.  Dis-
              able it again with --no-append.

              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 outgoing 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 pro-
              vided by a cloud (service-code) when the service name is omitted
              from the endpoint.

              If  --aws-sigv4 is provided several times, the last set value is
              used.

              Example:
               curl --aws-sigv4 "aws:amz:us-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.

              Providing --basic multiple times has no extra effect.

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

              See also --proxy-basic.

       --ca-native
              (TLS) Tells curl to use the CA store from the  native  operating
              system  to verify the peer. By default, curl otherwise uses a CA
              store provided in a single file or  directory,  but  when  using
              this option it interfaces the operating system's own vault.

              This  option  only  works  for curl on Windows when built to use
              OpenSSL. When curl on Windows is built  to  use  Schannel,  this
              feature is implied and curl then only uses the native CA store.

              curl  built  with  wolfSSL  also  supports this option (added in
              8.3.0).

              Providing --ca-native multiple times has no extra effect.   Dis-
              able it again with --no-ca-native.

              Example:
               curl --ca-native https://example.com

              See also --cacert, --capath and -k, --insecure. Added in 8.2.0.

       --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 variable.

              The  windows  version of curl automatically looks 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.

              (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 uses 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 (added in 7.60.0). This option is supported for back-
              ward  compatibility with other SSL engines; instead it is recom-
              mended to use Windows' store of root certificates  (the  default
              for Schannel).

              If  --cacert  is  provided  several times, the last set value is
              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 is ignored.

              If  --capath  is  provided  several times, the last set value is
              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 Certificate Status Request (aka. OCSP stapling) TLS
              extension.

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

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

              Providing --cert-status multiple  times  has  no  extra  effect.
              Disable it again with --no-cert-status.

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

              See also --pinnedpubkey.

       --cert-type <type>
              (TLS)  Tells  curl  what type the provided client certificate is
              using. PEM, DER, ENG and P12 are recognized types.

              The default type depends on the TLS backend and is usually  PEM,
              however  for  Secure  Transport  and  Schannel it is P12. If -E,
              --cert is a pkcs11: URI then ENG is the default type.

              If --cert-type is provided several times, the last set value  is
              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 proto-
              col.  The  certificate must be in PKCS#12 format if using Secure
              Transport, or PEM format if  using  any  other  engine.  If  the
              optional  password  is  not  specified, it is queried for on the
              terminal. Note that this option assumes a certificate file  that
              is  the private key and the client certificate concatenated. See
              -E, --cert and --key to specify them independently.

              In the <certificate> portion of the argument,  you  must  escape
              the  character  ":"  as "\:" so that it is not recognized as the
              password delimiter. Similarly, you must escape the character "\"
              as "\\" so that it is not recognized as an escape character.

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

              (iOS  and macOS only) If curl is built against Secure Transport,
              then the certificate string can either be the name of a certifi-
              cate/private  key in the system or user keychain, or the path to
              a PKCS#12-encoded certificate and private key. If  you  want  to
              use  a  file  from the current directory, please precede it with
              "./" prefix, in order to avoid confusion with a nickname.

              (Schannel only) Client certificates must be specified by a  path
              expression  to  a  certificate  store.  (Loading PFX is not sup-
              ported; you can import it to a store first). You can use "<store
              location>\<store  name>\<thumbprint>"  to refer to a certificate
              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,  CurrentUserGroupPolicy,
              LocalMachineGroupPolicy and LocalMachineEnterprise.

              If  -E,  --cert is provided several times, the last set value is
              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 --ciphers is provided several times, the last  set  value  is
              used.

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

              See also --tlsv1.3, --tls13-ciphers and --proxy-ciphers.

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

              Providing --compressed-ssh multiple times has no  extra  effect.
              Disable it again with --no-compressed-ssh.

              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.

              Response headers are not modified when saved,  so  if  they  are
              "interpreted"  separately  again  at  a  later  point they might
              appear to be saying that  the  content  is  (still)  compressed;
              while in fact it has already been decompressed.

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

              Providing --compressed multiple times has no extra effect.  Dis-
              able it again with --no-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 are used as if they were
              provided on the command line.

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

              If the parameter contains whitespace or starts with a colon  (:)
              or  equals sign (=), it must be specified enclosed within double
              quotes ("). Within double quotes the following escape  sequences
              are  available: \\, \", \t, \n, \r and \v. A backslash preceding
              any other letter is ignored.

              If the first non-blank column of a config line is a '#'  charac-
              ter, that line is treated as a comment.

              Only  write  one  option per physical line in the config file. A
              single line is required to be no more than 10  megabytes  (since
              8.2.0).

              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 exe-
              cutable is placed.

              On Windows two filenames are checked per location:  .curlrc  and
              _curlrc,  preferring  the  former.  Older  versions  on  Windows
              checked for _curlrc only.

              -K, --config can be used several times in a command line

              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 con-
              nects within the given period it continues - if not it exits.

              This option accepts decimal values. The decimal value  needs  to
              be provided using a dot (.) as decimal separator - not the local
              version even if it might be using another separator.

              The connection phase is considered complete when the DNS  lookup
              and requested TCP, TLS or QUIC handshakes are done.

              If  --connect-timeout  is  provided  several times, the last set
              value is 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 clus-
              ter  of  servers. This option is only used to establish the net-
              work 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".

              --connect-to can be used several times in a command line

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

              See also --resolve and -H, --header.

       -C, --continue-at <offset>
              Continue/Resume a previous file transfer at  the  given  offset.
              The  given offset is the exact number of bytes that are 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 is not 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 -C, --continue-at is provided several  times,  the  last  set
              value is 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 opera-
              tions. If no cookies are known, no data is written. The file  is
              created  using  the  Netscape cookie file format. If you set the
              file name to a single dash, "-", the cookies are written to std-
              out.

              The  file  specified with -c, --cookie-jar is only used for out-
              put. No cookies are read from the file. To read cookies, use the
              -b, --cookie option. Both options can specify the same file.

              This  command line option activates the cookie engine that makes
              curl record and use cookies. The -b, --cookie option also  acti-
              vates it.

              If  the  cookie  jar  cannot be created or written to, the whole
              curl operation does not fail or even report  an  error  clearly.
              Using  -v,  --verbose  gets a warning displayed, but that is the
              only visible feedback you get about this possibly lethal  situa-
              tion.

              If  -c,  --cookie-jar  is  provided  several times, the last set
              value is 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".  This  makes  curl use the cookie
              header with this content explicitly in all outgoing  request(s).
              If  multiple  requests  are done due to authentication, followed
              redirects or similar, they all get this cookie passed on.

              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 makes curl record  incom-
              ing  cookies, which may be handy if you are using this in combi-
              nation with the -L, --location option or do multiple URL  trans-
              fers  on  the  same  invoke. If the file name is exactly a minus
              ("-"), curl instead reads 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  are  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 never
              matches. To address this, set a domain in Set-Cookie line (doing
              that  includes  subdomains) or preferably: use the Netscape for-
              mat.

              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.

              -b, --cookie can be used several times in a command line

              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 cre-
              ates  the  necessary  local  directory hierarchy as needed. This
              option creates the directories mentioned with the  -o,  --output
              option combined with the path possibly set with --output-dir. If
              the combined output file name  uses  no  directory,  or  if  the
              directories  it  mentions already exist, no directories are cre-
              ated.

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

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

              Providing --create-dirs multiple  times  has  no  extra  effect.
              Disable it again with --no-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 supported 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 --create-file-mode is provided several times,  the  last  set
              value is 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 line feeds to carriage return plus line feeds
              in upload. Useful for MVS (OS/390).

              (SMTP added in 7.40.0)

              Providing --crlf multiple times has no extra effect.  Disable it
              again with --no-crlf.

              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 Revoca-
              tion List that may specify peer certificates that are to be con-
              sidered revoked.

              If  --crlfile  is  provided several times, the last set value is
              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 negotiations.

              If this option is  set,  the  default  curves  list  built  into
              OpenSSL are ignored.

              If  --curves  is  provided  several times, the last set value is
              used.

              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.

              --data-ascii can be used several times in a command line

              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  pro-
              cessing whatsoever.

              If  you  start  the data with the letter @, the rest should be a
              filename. Data is posted in a similar manner as -d, --data does,
              except that newlines and carriage returns are preserved and con-
              versions 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 con-
              tent-type    to   octet-stream:   -H   "Content-Type:   applica-
              tion/octet-stream".

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

              --data-binary can be used several times in a command line

              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 interpretation of the @ character.

              --data-raw can be used several times in a command line

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

              See also -d, --data.

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

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

              content
                     This  makes curl URL-encode the content and pass that on.
                     Just be careful so that the content does not contain  any
                     = or @ symbols, as that makes the syntax match one of the
                     other cases below!

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

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

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

              name@filename
                     This  makes 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, result-
                     ing in name=urlencoded-file-content. Note that  the  name
                     is expected to be URL-encoded already.

              --data-urlencode can be used several times in a command line

              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 makes
              curl pass the data to the server using the content-type applica-
              tion/x-www-form-urlencoded. Compare to -F, --form.

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

              If any of these options is used more than once on the same  com-
              mand  line, the data pieces specified are merged with a separat-
              ing &-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 new-
              lines are stripped out. If you do not want the  @  character  to
              have a special interpretation use --data-raw instead.

              The  data  for this option is passed on to the server exactly as
              provided on the command line. curl does not convert,  change  or
              improve it. It is up to the user to provide the data in the cor-
              rect form.

              -d, --data can be used several times in a command line

              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  is  mutually  exclusive to -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 service ticket,  which  is  a  matter  of
                     realm policy.

              always Unconditionally allow the server to delegate.

              If --delegation is provided several times, the last set value is
              used.

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

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

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

              Providing  --digest multiple times has no extra effect.  Disable
              it again with --no-digest.

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

              See also -u, --user, --proxy-digest and --anyauth.  This  option
              is mutually exclusive to --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 normally first attempts to
              use  EPRT  before using PORT, but with this option, it uses PORT
              right away. EPRT is an extension to the original  FTP  protocol,
              and does not work on all servers, but enables 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 has 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.

              Providing --disable-eprt multiple times  has  no  extra  effect.
              Disable it again with --no-disable-eprt.

              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 normally first attempts to use
              EPSV before PASV, but with this option, it does not try 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 has 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.

              Providing --disable-epsv multiple times  has  no  extra  effect.
              Disable it again with --no-disable-epsv.

              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 is not read  or  used.  See  the  -K,  --config  for
              details on the default config file search path.

              Prior  to  7.50.0 curl supported the short option name q but not
              the long option name disable.

              Providing -q, --disable multiple  times  has  no  extra  effect.
              Disable it again with --no-disable.

              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 probably most useful when  the  URL  is  being
              provided at runtime or similar.

              Providing --disallow-username-in-url multiple times has no extra
              effect.  Disable it again with --no-disallow-username-in-url.

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

              If --dns-interface is provided several times, the last set value
              is used.

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

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

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

              If --dns-ipv4-addr is provided several times, the last set value
              is 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 underlying libcurl was  built  to  support  c-
              ares.

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

              If --dns-ipv6-addr is provided several times, the last set value
              is 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  underlying  libcurl was built to support c-
              ares.

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

              If  --dns-servers  is provided several times, the last set value
              is 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  underlying  libcurl was built to support c-
              ares.

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

              Providing --doh-cert-status multiple times has no extra  effect.
              Disable it again with --no-doh-cert-status.

              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).

              Providing  --doh-insecure  multiple  times  has no extra effect.
              Disable it again with --no-doh-insecure.

              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 also applies  to
              DoH  since  the  name  lookups take place over SSL. However, the
              certificate verification settings are not inherited but are con-
              trolled separately via --doh-insecure and --doh-cert-status.

              This  option  is unset if an empty string "" is used as the URL.
              (Added in 7.85.0)

              If --doh-url is provided several times, the last  set  value  is
              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 creates
              an empty file.

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

              Having multiple transfers in one set  of  operations  (i.e.  the
              URLs  in  one -:, --next clause), appends them to the same file,
              separated by a blank line.

              If -D, --dump-header is provided several  times,  the  last  set
              value is used.

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

              See also -o, --output.

       --egd-file <file>
              (TLS) Deprecated option (added in 7.84.0). Prior to that it only
              had an effect on curl if built to use old versions of OpenSSL.

              Specify the path name to the Entropy  Gathering  Daemon  socket.
              The  socket  is  used  to seed the random engine for SSL connec-
              tions.

              If --egd-file is provided several times, the last set  value  is
              used.

              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 opera-
              tions. Use --engine list to print a list of build-time supported
              engines.  Note  that  not all (and possibly none) of the engines
              may be available at runtime.

              If --engine is provided several times, the  last  set  value  is
              used.

              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 spe-
              cific 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.

              If  --etag-compare is provided several times, the last set value
              is used.

              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.

              If --etag-save is provided several times, the last set value  is
              used.

              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 response when curl emits an  Expects:  100-continue
              header  in  its  request. By default curl waits one second. This
              option accepts decimal values! When curl stops waiting, it  con-
              tinues as if the response has been received.

              The  decimal  value needs to provided using a dot (.) as decimal
              separator - not the local version even  if  it  might  be  using
              another separator.

              If  --expect100-timeout  is provided several times, the last set
              value is used.

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

              See also --connect-timeout.

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

              When curl is used to do multiple transfers on the command  line,
              it  attempts  to  operate  on  each  given  URL,  one by one. By
              default, it ignores errors if there are more URLs given and  the
              last  URL's  success  determines the error code curl returns. So
              early failures are "hidden" by subsequent successful transfers.

              Using this option, curl instead returns 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 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 there-
              fore contained by -:, --next.

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

              Providing --fail-early multiple times has no extra effect.  Dis-
              able it again with --no-fail-early.

              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 returns an HTML document stating
              so  (which  often also describes why and more). This flag allows
              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 circumstances but without saving the content.

              Providing --fail-with-body multiple times has no  extra  effect.
              Disable it again with --no-fail-with-body.

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

              See  also  -f,  --fail and --fail-early. This option is mutually
              exclusive to -f, --fail. Added in 7.76.0.

       -f, --fail
              (HTTP) Fail fast with no output at all on server errors. This is
              useful  to  enable  scripts and users 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 prevents curl from  out-
              putting that and return error 22.

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

              Providing  -f,  --fail multiple times has no extra effect.  Dis-
              able it again with --no-fail.

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

              See also --fail-with-body and --fail-early. This option is mutu-
              ally exclusive to --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 starts sending applica-
              tion  data  before verifying the server's Finished message, thus
              saving a round trip when performing a full handshake.

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

              Providing  --false-start  multiple  times  has  no extra effect.
              Disable it again with --no-false-start.

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

              See also --tcp-fastopen.

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

              If  --form-escape  is provided several times, the last set value
              is used.

              Example:
               curl --form-escape -F 'field\name=curl' -F '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
              is any possibility that the string value may accidentally  trig-
              ger the '@' or '<' features of -F, --form.

              --form-string can be used several times in a command line

              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 emu-
              late 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 mul-
              tipart mail message to transmit.

              This  enables  uploading of binary files etc. To force the 'con-
              tent' 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 not subject to buffering and is instead  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  is  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 similar to:

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

              or

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

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

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

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

               curl -F "file=@\"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 backslash within the filename must be escaped by
              backslash.

              Quoting  must  also  be  applied to non-file data if it contains
              semicolons, leading/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 comments 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 multi-
              part: it can be followed by a content type specification.
              - a multipart can be terminated with a '=)' argument.

              Example: the following command sends an SMTP mime email consist-
              ing 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, limiting lines length to 76 characters.

              Example:  send  multipart mail with a quoted-printable text mes-
              sage and a base64 attached file:

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

              See further examples and details in the MANUAL.

              -F, --form can be used several times in a command line

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

              See also  -d,  --data,  --form-string  and  --form-escape.  This
              option  is  mutually  exclusive to -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 --ftp-account is provided several times, the last  set  value
              is 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" tells the server to retrieve the username  from  the
              certificate.

              If --ftp-alternative-to-user is provided several times, the last
              set value is used.

              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  instead  attempts  to
              create missing directories.

              Providing  --ftp-create-dirs multiple times has no extra effect.
              Disable it again with --no-ftp-create-dirs.

              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 follow-
              ing alternatives:

              multicwd
                     curl does a single CWD operation for each  path  part  in
                     the  given URL. For deep hierarchies this means many com-
                     mands. 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 does SIZE, RETR, STOR etc
                     and give a full path to the server  for  all  these  com-
                     mands. This is the fastest behavior.

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

              If --ftp-method is provided several times, the last set value is
              used.

              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 behavior, but using this option can be used  to
              override a previous -P, --ftp-port option.

              Reversing  an enforced passive really is not doable but you must
              then instead enforce the correct -P, --ftp-port again.

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

              Providing  --ftp-pasv  multiple times has no extra effect.  Dis-
              able it again with --no-ftp-pasv.

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

              See also --disable-epsv.

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

              interface
                     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 connection

              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.

              If  -P, --ftp-port is provided several times, the last set value
              is used.

              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.

              Providing  --ftp-pret  multiple times has no extra effect.  Dis-
              able it again with --no-ftp-pret.

              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 reuses the same IP address  it  already
              uses for the control connection.

              This option is enabled by default (added in 7.74.0).

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

              Providing --ftp-skip-pasv-ip multiple times has no extra effect.
              Disable it again with --no-ftp-skip-pasv-ip.

              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 does not initiate the
              shutdown, but instead waits for the server to do  it,  and  does
              not  reply to the shutdown from the server. The active mode ini-
              tiates the shutdown and waits for a reply from the server.

              Providing --ftp-ssl-ccc-mode multiple times has no extra effect.
              Disable it again with --no-ftp-ssl-ccc-mode.

              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 authenticating. The rest of the control channel com-
              munication  is be unencrypted. This allows NAT routers to follow
              the FTP transaction. The default mode is passive.

              Providing --ftp-ssl-ccc multiple  times  has  no  extra  effect.
              Disable it again with --no-ftp-ssl-ccc.

              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 authentication, but non-encrypted  data  transfers
              for  efficiency.  Fails the transfer if the server does not sup-
              port SSL/TLS.

              Providing --ftp-ssl-control multiple times has no extra  effect.
              Disable it again with --no-ftp-ssl-control.

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

              See also --ssl.

       -G, --get
              When used, this option makes 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 is appended to the URL with a '?' separator.

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

              Providing -G, --get multiple times has no extra effect.  Disable
              it again with --no-get.

              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  let-
              ters  are  not  normal  legal  URL  contents  but they should be
              encoded according to the URI standard.

              Providing -g, --globoff multiple  times  has  no  extra  effect.
              Disable it again with --no-globoff.

              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 addresses 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  connec-
              tion  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 --happy-eyeballs-timeout-ms is provided  several  times,  the
              last set value is 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-clientip
              (HTTP)  Sets  a client IP in HAProxy PROXY protocol v1 header at
              the beginning of the connection.

              For valid requests, IPv4 addresses must be indicated as a series
              of exactly 4 integers in the range [0..255] inclusive written in
              decimal representation separated by exactly one dot between each
              other.  Heading  zeroes are not permitted in front of numbers in
              order to avoid any possible confusion with octal  numbers.  IPv6
              addresses  must  be  indicated as series of 4 hexadecimal digits
              (upper or lower case) delimited by colons  between  each  other,
              with  the acceptance of one double colon sequence to replace the
              largest acceptable range of consecutive zeroes. The total number
              of decoded bits must exactly be 128.

              Otherwise,  any string can be accepted for the client IP and get
              sent.

              It replaces --haproxy-protocol if used, it is not  necessary  to
              specify both flags.

              This  option  is  primarily useful when sending test requests to
              verify a service is working as intended.

              If --haproxy-clientip is provided several times,  the  last  set
              value is used.

              Example:
               curl --haproxy-clientip $IP

              See also -x, --proxy. Added in 8.2.0.

       --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 expects this header.

              Providing --haproxy-protocol multiple times has no extra effect.
              Disable it again with --no-haproxy-protocol.

              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.

              Providing  -I,  --head multiple times has no extra effect.  Dis-
              able it again with --no-head.

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

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

       -H, --header <header/@file>
              (HTTP IMAP SMTP) Extra header to include  in  information  sent.
              When  used  within  an  HTTP request, it is added to the regular
              request headers.

              For an IMAP or SMTP MIME uploaded mail  built  with  -F,  --form
              options,  it is prepended to the resulting MIME document, effec-
              tively including it at the mail global level. It does not affect
              raw uploaded mails (Added in 7.56.0).

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

              curl  makes  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 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 @- makes
              curl read the header file from stdin. Added in 7.55.0.

              Please note that most anti-spam utilities check the presence and
              value  of  several  MIME mail headers: these are "From:", "To:",
              "Date:" and "Subject:" among others and  should  be  added  with
              this option.

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

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

              WARNING: headers set with  this  option  are  set  in  all  HTTP
              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.

              -H, --header can be used several times in a command line

              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
               curl -H @headers.txt https://example.com

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

       -h, --help <category>
              Usage help. This lists all curl command line options within  the
              given category.

              If  no  argument is provided, curl displays only the most impor-
              tant command line arguments.

              For category all, curl displays help for all options.

              If category is specified, curl displays all available help cate-
              gories.

              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 refuses the connection with the host unless the
              md5sums match.

              If --hostpubmd5 is provided several times, the last set value is
              used.

              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  refuses  the  connection
              with the host unless the hashes match.

              This  feature requires libcurl to be built with libssh2 and does
              not work with other SSH backends.

              If --hostpubsha256 is provided several times, the last set value
              is used.

              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 is used.  After
              a  completed transfer, the cache is saved to the file name again
              if it has been modified.

              If curl is told to use HTTP:// for a transfer involving  a  host
              name  that exists in the HSTS cache, it upgrades the transfer to
              use HTTPS. Each HSTS cache entry has  an  individual  life  time
              after which the upgrade is no longer performed.

              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 loads  contents  from
              all the files but the last one is used for saving.

              --hsts can be used several times in a command line

              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  response  without headers and therefore you can
              also connect with this to  non-HTTP  servers  and  still  get  a
              response   since  curl  simply  transparently  downgrades  -  if
              allowed.

              HTTP/0.9 is disabled by default (added in 7.66.0)

              Providing --http0.9 multiple times has no extra effect.  Disable
              it again with --no-http0.9.

              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.

              Providing -0, --http1.0 multiple times has no extra effect.

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

              See also --http0.9 and --http1.1. This option is mutually exclu-
              sive  to  --http1.1  and --http2 and --http2-prior-knowledge and
              --http3.

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

              Providing --http1.1 multiple times has no extra effect.

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

              See also -0, --http1.0 and --http0.9. This  option  is  mutually
              exclusive  to -0, --http1.0 and --http2 and --http2-prior-knowl-
              edge and --http3.

       --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
              still  do  HTTP/2 the standard way with negotiated protocol ver-
              sion in the TLS handshake.

              Providing --http2-prior-knowledge multiple times  has  no  extra
              effect.  Disable it again with --no-http2-prior-knowledge.

              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  is mutually exclusive to --http1.1 and -0, --http1.0 and
              --http2 and --http3.

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

              For HTTPS, this means curl negotiates HTTP/2 in  the  TLS  hand-
              shake. curl does this by default.

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

              When curl uses HTTP/2 over HTTPS, it does not itself  insist  on
              TLS 1.2 or higher even though that is required by the specifica-
              tion. A user can add this version requirement with --tlsv1.2.

              Providing --http2 multiple times has no extra effect.

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

              See also --http1.1, --http3 and --no-alpn. --http2 requires that
              the  underlying libcurl was built to support HTTP/2. This option
              is  mutually  exclusive  to  --http1.1  and  -0,  --http1.0  and
              --http2-prior-knowledge and --http3.

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

              Instructs curl to use HTTP/3 to the host in  the  URL,  with  no
              fallback  to  earlier HTTP versions. HTTP/3 can only be used for
              HTTPS and not for HTTP URLs. For HTTP, this option  triggers  an
              error.

              This  option  allows a user to avoid using the Alt-Svc method of
              upgrading to HTTP/3 when you know that the target speaks  HTTP/3
              on the given host and port.

              This  option  makes  curl  fail  if  a QUIC connection cannot be
              established, it does not attempt any other HTTP versions on  its
              own. Use --http3 for similar functionality with a fallback.

              Providing --http3-only multiple times has no extra effect.

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

              See  also  --http1.1, --http2 and --http3. --http3-only requires
              that the underlying libcurl was built to  support  HTTP/3.  This
              option  is mutually exclusive to --http1.1 and -0, --http1.0 and
              --http2  and  --http2-prior-knowledge  and  --http3.  Added   in
              7.88.0.

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

              Tells curl to try HTTP/3 to the host in the URL, but fallback to
              earlier  HTTP  versions  if  the HTTP/3 connection establishment
              fails. HTTP/3 is only available for HTTPS and not for HTTP URLs.

              This option allows a user to avoid using the Alt-Svc  method  of
              upgrading  to HTTP/3 when you know that the target speaks HTTP/3
              on the given host and port.

              When asked to use HTTP/3, curl issues a separate attempt to  use
              older HTTP versions with a slight delay, so if the HTTP/3 trans-
              fer fails or is slow, curl still tries to proceed with an  older
              HTTP version.

              Use --http3-only for similar functionality without a fallback.

              Providing --http3 multiple times has no extra effect.

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

              See also --http1.1 and --http2. --http3 requires that the under-
              lying libcurl was built to support HTTP/3. This option is  mutu-
              ally  exclusive  to  --http1.1 and -0, --http1.0 and --http2 and
              --http2-prior-knowledge and --http3-only. 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
              reports incorrect Content-Length for files larger than  2  giga-
              bytes.

              For FTP, this makes curl skip the SIZE command to figure out the
              size before downloading a file.

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

              Providing  --ignore-content-length  multiple  times has no extra
              effect.  Disable it again with --no-ignore-content-length.

              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 include things like server name, cookies,
              date of the document, HTTP version and more...

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

              Prior to 7.75.0 curl did not print the headers if -f, --fail was
              used  in  combination  with  this  option  and  there  was error
              reported by server.

              Providing -i, --include multiple  times  has  no  extra  effect.
              Disable it again with --no-include.

              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 secure 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 veri-
              fies  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" subdirectory, which contains
              host names and their public keys.

              WARNING: using this option makes the transfer insecure.

              When curl uses secure protocols it trusts responses  and  allows
              for  example  HSTS and Alt-Svc information to be stored and used
              subsequently. Using -k, --insecure can make curl trust  and  use
              such information from malicious servers.

              Providing  -k,  --insecure  multiple  times has no extra effect.
              Disable it again with --no-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/

              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 informa-
              tion  about  Linux  VRF:   https://www.kernel.org/doc/Documenta-
              tion/networking/vrf.txt

              If  --interface is provided several times, the last set value is
              used.

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

              See also --dns-interface.

       --ipfs-gateway <URL>
              Specifies which gateway to use for  IPFS  and  IPNS  URLs.   Not
              specifying  this  argument  will  let  cURL try to automatically
              check  if  IPFS_GATEWAY  environment  variable  is  set,  or  if
              ~/.ipfs/gateway plain text file exists.

              If  you run a local IPFS node, this gateway is by default avail-
              able under http://localhost:8080. A full example URL would  look
              like:

               curl --ipfs-gateway http://localhost:8080 ipfs://bafybeigagd5nmnn2iys2f3doro7ydrevyr2mzarwidgadawmamiteydbzi

              You can also specify publicly available gateways. One such gate-
              way is https://ipfs.io. A full example url would look like:

               curl --ipfs-gateway https://ipfs.io ipfs://bafybeigagd5nmnn2iys2f3doro7ydrevyr2mzarwidgadawmamiteydbzi

              There are many public IPFS gateways. As a starting point to find
              one that works for your case, consult this page:

               https://ipfs.github.io/public-gateway-checker/

              A  word  of caution! When you opt to go for a remote gateway you
              should be aware that you completely trust the gateway.  This  is
              fine  in  local  gateways  as  you host it yourself. With remote
              gateways there could potentially be a malicious actor  returning
              you  data  that  does not match the request you made, inspect or
              even interfere with the request.  You  won't  notice  this  when
              using cURL.  A mitigation could be to go for a "trustless" gate-
              way. This means you locally verify that the  data.  Consult  the
              docs page on trusted vs trustless: https://docs.ipfs.tech/refer-
              ence/http/gateway/#trusted-vs-trustless

              If --ipfs-gateway is provided several times, the last set  value
              is used.

              Example:
               curl --ipfs-gateway https://example.com ipfs://

              See also -h, --help and -M, --manual. Added in 8.4.0.

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

              Providing -4, --ipv4 multiple times has no extra effect.

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

              See also --http1.1 and --http2. This option is  mutually  exclu-
              sive to -6, --ipv6.

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

              Providing -6, --ipv6 multiple times has no extra effect.

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

              See also --http1.1 and --http2. This option is  mutually  exclu-
              sive to -4, --ipv4.

       --json <data>
              (HTTP)  Sends  the  specified JSON data in a POST request to the
              HTTP server. --json works as a shortcut  for  passing  on  these
              three options:

               --data [arg]
               --header "Content-Type: application/json"
               --header "Accept: application/json"

              There  is no verification that the passed in data is actual JSON
              or that the syntax is correct.

              If you start the data with the letter @, the rest  should  be  a
              file  name  to  read  the data from, or a single dash (-) if you
              want curl to read the data from stdin. Posting data from a  file
              named  'foobar'  would  thus  be done with --json @foobar and to
              instead read the data from stdin, use --json @-.

              If this option is used more than once on the same command  line,
              the  additional  data  pieces  are  concatenated to the previous
              before sending.

              The headers this option sets can be overridden with -H, --header
              as usual.

              --json can be used several times in a command line

              Examples:
               curl --json '{ "drink": "coffe" }' https://example.com
               curl --json '{ "drink":' --json ' "coffe" }' https://example.com
               curl --json @prepared https://example.com
               curl --json @- https://example.com < json.txt

              See  also  --data-binary and --data-raw. This option is mutually
              exclusive to -F, --form and -I, --head  and  -T,  --upload-file.
              Added in 7.82.0.

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

              Providing -j, --junk-session-cookies multiple times has no extra
              effect.  Disable it again with --no-junk-session-cookies.

              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).  Keepalives are
              used by the TCP stack to detect broken networks on idle  connec-
              tions.  The  number  of missed keepalive probes before declaring
              the connection down is OS dependent and is  commonly  9  or  10.
              This option has no effect if --no-keepalive is used.

              If unspecified, the option defaults to 60 seconds.

              If  --keepalive-time  is  provided  several  times, the last set
              value is used.

              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  pro-
              vided  private  key  is. DER, PEM, and ENG are supported. If not
              specified, PEM is assumed.

              If --key-type is provided several times, the last set  value  is
              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 pri-
              vate key in this separate file. For SSH, if not specified,  curl
              tries   the  following  candidates  in  order:  '~/.ssh/id_rsa',
              '~/.ssh/id_dsa', './id_rsa', './id_dsa'.

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

              If curl is built against Secure Transport or Schannel then  this
              option is ignored for TLS protocols (HTTPS, etc). Those backends
              expect the private key to be already present in the keychain  or
              PKCS#12 file containing the certificate.

              If --key is provided several times, the last set value is 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' is used.

              If --krb is provided several times, the last set value is used.

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

              See also --delegation and --ssl. --krb requires that the  under-
              lying libcurl was built to support Kerberos.

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

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

              If --libcurl is provided several times, the last  set  value  is
              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 uploads. 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.   Appending 'k' or 'K' counts the number as kilobytes,
              'm' or 'M' makes it megabytes, while 'g' or 'G' makes  it  giga-
              bytes.  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 sec-
              onds.

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

              If --limit-rate is provided several times, the last set value is
              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 --rate, -Y, --speed-limit and -y, --speed-time.

       -l, --list-only
              (FTP POP3 SFTP) (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  for-
              mat.  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 include sub-directories and symbolic links.

              (SFTP)  When  listing  an  SFTP  directory, this switch forces a
              name-only view, one per line.  This is especially useful if  the
              user  wants  to  machine-parse the contents of an SFTP directory
              since the normal directory view provides more  information  than
              just file names.

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

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

              Providing  -l,  --list-only  multiple times has no extra effect.
              Disable it again with --no-list-only.

              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 so setting this range to  something
              too narrow might cause unnecessary connection setup failures.

              If --local-port is provided several times, the last set value is
              used.

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

              See also -g, --globoff.

       --location-trusted
              (HTTP) Like -L, --location, but allows sending the name +  pass-
              word 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 send your authentication info (which is plain-
              text in the case of HTTP Basic authentication).

              Providing --location-trusted multiple times has no extra effect.
              Disable it again with --no-location-trusted.

              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 location (indicated with a Location: header and a
              3XX  response  code), this option makes curl redo the request on
              the new place. If  used  together  with  -i,  --include  or  -I,
              --head, headers from all requested pages are shown.

              When  authentication is used, curl only sends its credentials to
              the initial host. If a redirect takes curl to a different  host,
              it  does  not  get  the  user+password pass on. See also --loca-
              tion-trusted on how to change this.

              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
              sends the following request with a GET if the HTTP response  was
              301,  302,  or 303. If the response code was any other 3xx code,
              curl resends 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.

              Providing -L, --location multiple times  has  no  extra  effect.
              Disable it again with --no-location.

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

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

       --login-options <options>
              (IMAP  LDAP  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 the IETF draft
              https://datatracker.ietf.org/doc/html/draft-earhart-url-smtp-00.

              Since 8.2.0, IMAP supports the login option "AUTH=+LOGIN".  With
              this  option,  curl uses the plain (not SASL) LOGIN IMAP command
              even if the server advertises SASL authentication.  Care  should
              be  taken  in  using this option, as it sends your password over
              the network in plain text. This does not work if the IMAP server
              disables the plain LOGIN (e.g. to prevent password snooping).

              If --login-options is provided several times, the last set value
              is used.

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

              See also -u, --user.

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

              If --mail-auth is provided several times, the last set value  is
              used.

              Example:
               curl --mail-auth user@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.

              If --mail-from is provided several times, the last set value  is
              used.

              Example:
               curl --mail-from user@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
              aborts 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  makes  curl
              ignore errors and proceed with the remaining valid recipients.

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

              Providing  --mail-rcpt-allowfails  multiple  times  has no extra
              effect.  Disable it again with --no-mail-rcpt-allowfails.

              Example:
               curl --mail-rcpt-allowfails --mail-rcpt dest@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 RFC 5321).

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

              --mail-rcpt can be used several times in a command line

              Example:
               curl --mail-rcpt user@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 does not start and curl returns with exit code 63.

              A size modifier may be used. For example, Appending 'k'  or  'K'
              counts  the  number as kilobytes, 'm' or 'M' makes it megabytes,
              while 'g' or 'G' makes it gigabytes. Examples: 200K, 3m and  1G.
              (Added in 7.58.0)

              NOTE:  before  curl 8.4.0, when the file size is not known prior
              to download, for such files this option has no  effect  even  if
              the file transfer ends up being larger than this given limit.

              Starting  with curl 8.4.0, this option aborts the transfer if it
              reaches the threshold during transfer.

              If --max-filesize is provided several times, the last set  value
              is used.

              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 --max-redirs is provided several times, the last set value is
              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 each transfer to take.
              This is useful for preventing your batch jobs from  hanging  for
              hours  due  to  slow  networks  or links going down. This option
              accepts decimal values.

              If you enable retrying the transfer (--retry) then  the  maximum
              time counter is reset each time the transfer is retried. You can
              use --retry-max-time to limit the retry time.

              The decimal value needs to provided using a dot (.)  as  decimal
              separator  -  not  the  local  version even if it might be using
              another separator.

              If -m, --max-time is provided several times, the last set  value
              is used.

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

              See also --connect-timeout and --retry-max-time.

       --metalink
              This  option was previously used to specify a Metalink resource.
              Metalink support is disabled in curl for security reasons (added
              in 7.78.0).

              If  --metalink  is provided several times, the last set value is
              used.

              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  sup-
              port.   Use   -V,   --version  to  see  if  your  curl  supports
              GSS-API/SSPI or SPNEGO.

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

              Providing --negotiate multiple times has no extra effect.

              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.

              It abides by --netrc-optional if specified.

              If --netrc-file is provided several times, the last set value is
              used.

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

              See also -n, --netrc, -u, --user and -K, --config.  This  option
              is mutually exclusive to -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.

              Providing --netrc-optional multiple times has no  extra  effect.
              Disable it again with --no-netrc-optional.

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

              See  also --netrc-file. This option is mutually exclusive to -n,
              --netrc.

       -n, --netrc
              Makes curl scan the .netrc 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  enables  user  authentication.  See
              netrc(5)  and  ftp(1)  for details on the file format. Curl does
              not complain if that file does not have  the  right  permissions
              (it  should  be neither world- nor group-readable). The environ-
              ment variable "HOME" is used to find the home directory.

              On Windows two filenames in  the  home  directory  are  checked:
              .netrc and _netrc, preferring the former. Older versions on Win-
              dows checked for _netrc only.

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

               machine host.domain.com
               login myself
               password secret

              Providing -n, --netrc multiple times has no extra effect.   Dis-
              able it again with --no-netrc.

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

              See  also --netrc-file, -K, --config and -u, --user. This option
              is mutually exclusive to --netrc-file and --netrc-optional.

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

              -:,  --next  resets  all local options and only global ones 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  com-
              mand line:

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

              -:, --next can be used several times in a command line

              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.

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

              Note that this is the negated option name  documented.  You  can
              use --alpn to enable ALPN.

              Providing --no-alpn multiple times has no extra effect.  Disable
              it again with --alpn.

              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.

       -N, --no-buffer
              Disables the buffering of the output stream. In normal work sit-
              uations, curl uses a standard buffered output  stream  that  has
              the  effect  that it outputs the data in chunks, not necessarily
              exactly when the data arrives. Using this option  disables  that
              buffering.

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

              Providing -N, --no-buffer multiple times has  no  extra  effect.
              Disable it again with --buffer.

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

              See also -#, --progress-bar.

       --no-clobber
              When   used   in   conjunction   with   the  -o,  --output,  -J,
              --remote-header-name, -O,  --remote-name,  or  --remote-name-all
              options,  curl  avoids  overwriting  files  that  already exist.
              Instead, a dot and a number gets appended to  the  name  of  the
              file  that  would  be created, up to filename.100 after which it
              does not create any file.

              Note that this is the negated option name documented.   You  can
              thus  use  --clobber  to  enforce  the  clobbering,  even if -J,
              --remote-header-name is specified.

              Providing --no-clobber multiple times has no extra effect.  Dis-
              able it again with --clobber.

              Example:
               curl --no-clobber --output local/dir/file https://example.com

              See also -o, --output and -O, --remote-name. Added in 7.83.0.

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

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

              Providing  --no-keepalive  multiple  times  has no extra effect.
              Disable it again with --keepalive.

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

              See also --keepalive-time.

       --no-npn
              (HTTPS) curl never uses NPN, this option has no effect (added in
              7.86.0).

              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 sup-
              port with the server during https sessions.

              Providing --no-npn multiple times has no extra effect.   Disable
              it again with --npn.

              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.

       --no-progress-meter
              Option to switch off the progress meter output without muting or
              otherwise  affecting 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.

              Providing   --no-progress-meter  multiple  times  has  no  extra
              effect.  Disable it again with --progress-meter.

              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.

              Providing  --no-sessionid  multiple  times  has no extra effect.
              Disable it again with --sessionid.

              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    local.com,    local.com:80,   and
              www.local.com, but not www.notlocal.com.

              This option overrides the environment variables that disable the
              proxy ('no_proxy' and 'NO_PROXY') (added in 7.53.0). If there is
              an environment variable disabling a proxy, you can  set  the  no
              proxy list to "" to override it.

              IP addresses specified to this option can be provided using CIDR
              notation (added in 7.86.0): an appended slash and number  speci-
              fies  the  number of "network bits" out of the address to use in
              the comparison. For example  "192.168.0.0/16"  would  match  all
              addresses starting with "192.168".

              If  --noproxy  is  provided several times, the last set value is
              used.

              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.

              Providing --ntlm-wb multiple times has no extra effect.

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

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

              Providing --ntlm multiple times has no extra effect.

              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 is mutually exclu-
              sive to --basic and --negotiate and --digest and --anyauth.

       --oauth2-bearer <token>
              (IMAP  LDAP  POP3  SMTP HTTP) Specify the Bearer Token for OAUTH
              2.0 server authentication. The Bearer Token is used in  conjunc-
              tion  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 --oauth2-bearer is provided several times, the last set value
              is used.

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

              See also --basic, --ntlm and --digest.

       --output-dir <dir>
              This option specifies the directory in  which  files  should  be
              stored, when -O, --remote-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
              fails unless --create-dirs is also used.

              If --output-dir is provided several times, the last set value is
              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 multiple documents, you should quote the URL and you
              can  use  '#' followed by a number in the <file> specifier. That
              variable is 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].example" -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 directo-
              ries dynamically. Specifying the output as '-' (a  single  dash)
              passes the output to stdout.

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

               curl example.com -o /dev/null

              Or for Windows:

               curl example.com -o nul

              -o, --output can be used several times in a command line

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

              Providing  --parallel-immediate  multiple  times  has  no  extra
              effect.  Disable it again with --no-parallel-immediate.

              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 simultane-
              ously.

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

              The default is 50.

              If  --parallel-max is provided several times, the last set value
              is used.

              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 manner.

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

              Providing -Z, --parallel multiple times  has  no  extra  effect.
              Disable it again with --no-parallel.

              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 --pass is provided several times, the last set value is 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 squashes or  merges  them  according  to
              standards but with this option set you tell it not to do that.

              Providing --path-as-is multiple times has no extra effect.  Dis-
              able it again with --no-path-as-is.

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

              See also --request-target.

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

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

              This option is independent of option -k, --insecure. If you  use
              both  options together then the peer is still verified by public
              key.

              PEM/DER support:

              OpenSSL and GnuTLS, wolfSSL (added in 7.43.0), mbedTLS ,  Secure
              Transport macOS 10.7+/iOS 10+ (7.54.1), Schannel (7.58.1)

              sha256 support:

              OpenSSL,  GnuTLS  and wolfSSL, mbedTLS (added in 7.47.0), Secure
              Transport macOS 10.7+/iOS 10+ (7.54.1), Schannel (7.58.1)

              Other SSL backends not supported.

              If --pinnedpubkey is provided several times, the last set  value
              is used.

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

              See also --hostpubsha256.

       --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. However, a server
              may  require  a  POST to remain a POST after such a redirection.
              This option is meaningful only when using -L, --location.

              Providing --post301 multiple times has no extra effect.  Disable
              it again with --no-post301.

              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. However, a server
              may  require  a  POST to remain a POST after such a redirection.
              This option is meaningful only when using -L, --location.

              Providing --post302 multiple times has no extra effect.  Disable
              it again with --no-post302.

              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 redirect-
              ion. This option is meaningful only when using -L, --location.

              Providing --post303 multiple times has no extra effect.  Disable
              it again with --no-post303.

              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:// pre-
              fix  to  specify  alternative  proxy  protocols.  Use socks4://,
              socks4a://, socks5:// or  socks5h://  to  request  the  specific
              SOCKS  version  to  be  used.  No  protocol specified makes curl
              default to SOCKS4.

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

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

              If  --preproxy  is provided several times, the last set value is
              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 standard, more informational, meter.

              This  progress  bar draws a single line of '#' characters across
              the screen and shows a percentage if the transfer size is known.
              For  transfers  without  a  known  size,  there  is a 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.

              Providing -#, --progress-bar multiple times has no extra effect.
              Disable it again with --no-progress-bar.

              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_UNSUP-
              PORTED_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.

              If --proto-default is provided several times, the last set value
              is used.

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

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

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

              Example, allow only HTTP and HTTPS on redirect:

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

              By default curl only allows HTTP, HTTPS, FTP and FTPS  on  redi-
              rects (added in 7.65.2). Specifying all or +all enables all pro-
              tocols on redirects, which is not good for security.

              If --proto-redir is provided several times, the last  set  value
              is used.

              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 evaluated left to right, are comma separated,  and
              are  each  a protocol name or 'all', optionally prefixed by zero
              or more modifiers. Available modifiers are:

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

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

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

              For example:

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

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

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

              Unknown and disabled protocols produce a  warning.  This  allows
              scripts to safely rely on being able to disable potentially dan-
              gerous 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.

              If  --proto  is  provided  several  times, the last set value is
              used.

              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  commu-
              nicating  with  the  given HTTP proxy. This might cause an extra
              request/response round-trip.

              Providing --proxy-anyauth multiple times has no extra effect.

              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.

              Providing --proxy-basic multiple times has no extra effect.

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

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

       --proxy-ca-native
              (TLS)  Tells  curl to use the CA store from the native operating
              system to verify the HTTPS proxy. By default,  curl  uses  a  CA
              store  provided  in  a  single file or directory, but when using
              this option it interfaces the operating system's own vault.

              This option only works for curl on Windows  when  built  to  use
              OpenSSL.  When  curl  on  Windows is built to use Schannel, this
              feature is implied and curl then only uses the native CA store.

              curl built with wolfSSL also  supports  this  option  (added  in
              8.3.0).

              Providing  --proxy-ca-native multiple times has no extra effect.
              Disable it again with --no-proxy-ca-native.

              Example:
               curl --ca-native https://example.com

              See also --cacert, --capath and -k, --insecure. Added in 8.2.0.

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

              If --proxy-cacert is provided several times, the last set  value
              is used.

              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.

              If --proxy-capath is provided several times, the last set  value
              is used.

              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.

              If --proxy-cert-type is provided several  times,  the  last  set
              value is used.

              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.

              If --proxy-cert is provided several times, the last set value is
              used.

              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.

              Specifies which ciphers to use in the connection  to  the  HTTPS
              proxy.  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 --proxy-ciphers is provided several times, the last set value
              is used.

              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.

              If --proxy-crlfile is provided several times, the last set value
              is used.

              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.

              Providing --proxy-digest multiple times has no extra effect.

              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  communi-
              cation  only  like  in CONNECT requests when you want a separate
              header sent to the proxy to what is sent to  the  actual  remote
              host.

              curl  makes  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 only mess things up for you.

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

              This  option can take an argument in @filename style, which then
              adds a header for each line in the input file (added in 7.55.0).
              Using @- makes curl read the headers from stdin.

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

              --proxy-header can be used several times in a command line

              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.

       --proxy-http2
              (HTTP) Tells curl to try negotiate HTTP version 2 with an  HTTPS
              proxy.  The  proxy  might  still only offer HTTP/1 and then curl
              sticks to using that version.

              This has no effect for any other kinds of proxies.

              Providing --proxy-http2 multiple  times  has  no  extra  effect.
              Disable it again with --no-proxy-http2.

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

              See also -x, --proxy. --proxy-http2 requires that the underlying
              libcurl was built to support HTTP/2. Added in 8.1.0.

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

              Providing --proxy-insecure multiple times has no  extra  effect.
              Disable it again with --no-proxy-insecure.

              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.

              If  --proxy-key-type  is  provided  several  times, the last set
              value is used.

              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.

              If --proxy-key is provided several times, the last set value  is
              used.

              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.

              Providing --proxy-negotiate multiple times has no extra effect.

              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.

              Providing --proxy-ntlm multiple times has no extra effect.

              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.

              If --proxy-pass is provided several times, the last set value is
              used.

              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 sepa-
              rated by ';'.

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

              If --proxy-pinnedpubkey is provided several times, the last  set
              value is 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.

              If --proxy-service-name is provided several times, the last  set
              value is used.

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

              See also --service-name and -x, --proxy.

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

              Providing  --proxy-ssl-allow-beast  multiple  times has no extra
              effect.  Disable it again with --no-proxy-ssl-allow-beast.

              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.

              Providing --proxy-ssl-auto-client-cert  multiple  times  has  no
              extra       effect.        Disable       it      again      with
              --no-proxy-ssl-auto-client-cert.

              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 --proxy-tls13-ciphers is provided several times, the last set
              value is used.

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

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

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

              If  --proxy-tlsauthtype  is provided several times, the last set
              value is used.

              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.

              If --proxy-tlspassword is provided several times, the  last  set
              value is used.

              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.

              If --proxy-tlsuser is provided several times, the last set value
              is used.

              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.

              Providing --proxy-tlsv1 multiple times has no extra effect.

              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  authentica-
              tion.

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

              On systems where it works, curl hides 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  still are visible for a moment before cleared. Such sensi-
              tive data should be retrieved from a file instead or similar and
              never used in clear text in a command line.

              If  -U,  --proxy-user  is  provided  several times, the last set
              value is 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:// it is treated as an HTTP proxy.
              Use socks4://, socks4a://, socks5:// or socks5h:// to request  a
              specific SOCKS version to be used.

              Unix domain sockets are supported for socks proxy. Set localhost
              for the host part. e.g. socks5h://localhost/path/to/socket.sock

              HTTPS proxy support works set with the https:// protocol  prefix
              for  OpenSSL  and  GnuTLS  (added  in 7.52.0). It also works for
              BearSSL, mbedTLS, rustls, Schannel, Secure Transport and wolfSSL
              (added in 7.87.0).

              Unrecognized  and  unsupported  proxy  protocols  cause an error
              (added  in  7.52.0).   Ancient  curl  versions  ignored  unknown
              schemes and used 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 is an environment variable setting a
              proxy, you can set proxy to "" to override it.

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

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

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

              When a proxy is used, the  active  FTP  mode  as  set  with  -P,
              --ftp-port, cannot be used.

              If  -x, --proxy is provided several times, the last set value is
              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 assumed at port 1080.

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

              Providing --proxy1.0 multiple times has no extra effect.

              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 makes curl
              tunnel the traffic through the proxy.  The  tunnel  approach  is
              made  with  the HTTP proxy CONNECT request and requires that the
              proxy allows direct connect to the remote port number curl wants
              to tunnel through to.

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

              Providing -p, --proxytunnel multiple times has no extra  effect.
              Disable it again with --no-proxytunnel.

              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 pub-
              lic key in this separate file.

              curl attempts to automatically extract the public key  from  the
              private  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.

              If --pubkey is provided several times, the  last  set  value  is
              used.

              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 commands are sent BEFORE the transfer takes  place
              (just  after  the  initial PWD command in an FTP transfer, to be
              exact). To make commands take place after a successful transfer,
              prefix them with a dash '-'.

              (FTP  only)  To make commands be sent after curl has changed the
              working directory, just before  the  file  transfer  command(s),
              prefix  the  command  with  a  '+'. This is not performed when a
              directory listing is performed.

              You may specify any number of commands.

              By default curl stops at first failure. To  make  curl  continue
              even  if  the command fails, prefix the command with an asterisk
              (*). Otherwise, if the server returns failure  for  one  of  the
              commands, the entire operation is 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.

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

              "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 oper-
                     and. The user operand is a decimal integer user ID.

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

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

              "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  path  name  of  the
                     current working directory.

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

              "rm file"
                     The rm command removes the file specified by the file op-
                     erand.

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

              "symlink source_file target_file"
                     See ln.

              -Q, --quote can be used several times in a command line

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

              See also -X, --request.

       --random-file <file>
              Deprecated  option.  This  option  is ignored (added in 7.84.0).
              Prior to that it only had an effect on curl if built to use  old
              versions of OpenSSL.

              Specify  the  path name to file containing random data. The data
              may be used to seed the random engine for SSL connections.

              If --random-file is provided several times, the last  set  value
              is used.

              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 docu-
              ment) 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 causes the server to reply with a multipart
              response, which is returned as-is by curl! Parsing or  otherwise
              transforming this response 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  charac-
              ter is given in the range, the server's response is unspecified,
              depending on the server's configuration.

              Many HTTP/1.1 servers do not have this feature enabled, so  that
              when  you  attempt  to  get a range, curl instead gets the whole
              document.

              FTP  and  SFTP  range  downloads   only   support   the   simple
              'start-stop'  syntax  (optionally  with one of the numbers omit-
              ted). FTP use depends on the extended FTP command SIZE.

              If -r, --range is provided several times, the last set value  is
              used.

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

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

       --rate <max request rate>
              Specify  the  maximum transfer frequency you allow curl to use -
              in number of transfer starts per  time  unit  (sometimes  called
              request  rate). Without this option, curl starts the next trans-
              fer as fast as possible.

              If given several URLs and a transfer completes faster  than  the
              allowed  rate,  curl waits until the next transfer is started to
              maintain the requested rate. This option has no effect when  -Z,
              --parallel is used.

              The request rate is provided as "N/U" where N is an integer num-
              ber and U is a time unit. Supported units are 's' (second),  'm'
              (minute),  'h'  (hour) and 'd' /(day, as in a 24 hour unit). The
              default time unit, if no "/U" is provided, is number  of  trans-
              fers per hour.

              If  curl  is  told  to allow 10 requests per minute, it does not
              start the next request until 6 seconds have  elapsed  since  the
              previous transfer was started.

              This  function  uses millisecond resolution. If the allowed fre-
              quency is set more than 1000 per second, it instead  runs  unre-
              stricted.

              When  retrying  transfers,  enabled  with  --retry, the separate
              retry delay logic is used and not this setting.

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

              If --rate is provided several times, the last set value is used.

              Examples:
               curl --rate 2/s https://example.com ...
               curl --rate 3/h https://example.com ...
               curl --rate 14/m https://example.com ...

              See also --limit-rate and --retry-delay. Added in 7.84.0.

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

              Providing  --raw multiple times has no extra effect.  Disable it
              again with --no-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  append  ";auto"  to  the  -e,
              --referer  URL  to  make curl automatically set the previous URL
              when it follows a Location: header. The ";auto"  string  can  be
              used alone, even if you do not set an initial -e, --referer.

              If  -e,  --referer is provided several times, the last set value
              is 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-provided  file
              name  contains a path, that is stripped off before the file name
              is used.

              The file is saved in the current directory, or in the  directory
              specified with --output-dir.

              If  the  server  specifies a file name and a file with that name
              already exists in the destination directory, it is not overwrit-
              ten  and  an  error  occurs  -  unless you allow it by using the
              --clobber option. If the server does not  specify  a  file  name
              then this option has no effect.

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

              This  feature  uses  the name from the "filename" field, it does
              not yet support the "filename*" field (filenames  with  explicit
              character sets).

              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 automatically by Windows or some
              third party software.

              Providing -J, --remote-header-name multiple times has  no  extra
              effect.  Disable it again with --no-remote-header-name.

              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  specific  URL  after
              --remote-name-all  has  been  used,  you  must  use  "-o  -"  or
              --no-remote-name.

              Providing  --remote-name-all multiple times has no extra effect.
              Disable it again with --no-remote-name-all.

              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 is 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 or use --output-dir.

              The  remote  file  name  to use for saving is extracted from the
              given URL, nothing else, and if it already exists  it  is  over-
              written.  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 is not overwritten.

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

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

              -O, --remote-name can be used several times in a command line

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

              See     also    --remote-name-all,    --output-dir    and    -J,
              --remote-header-name.

       -R, --remote-time
              Makes curl attempt to figure out the  timestamp  of  the  remote
              file  that  is getting downloaded, and if that is available make
              the local file get that same timestamp.

              Providing -R, --remote-time multiple times has no extra  effect.
              Disable it again with --no-remote-time.

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

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

       --remove-on-error
              When  curl  returns an error when told to save output in a local
              file, this option removes that saved file before  exiting.  This
              prevents  curl  from  leaving  a  partial file in the case of an
              error during transfer.

              If the output is not a file, this option has no effect.

              Providing --remove-on-error multiple times has no extra  effect.
              Disable it again with --no-remove-on-error.

              Example:
               curl --remove-on-error -o output https://example.com

              See also -f, --fail. Added in 7.83.0.

       --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 *".

              If  --request-target  is  provided  several  times, the last set
              value is used.

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

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

       -X, --request <method>
              Change the method to use when starting the transfer.

              HTTP           Specifies a custom request  method  to  use  when
                             communicating with the HTTP server. The specified
                             request method is used instead of the method oth-
                             erwise  used  (which  defaults  to GET). Read the
                             HTTP 1.1 specification for details  and  explana-
                             tions.  Common  additional  HTTP requests include
                             PUT and DELETE,  but  related  technologies  like
                             WebDAV offers PROPFIND, COPY, MOVE and more.

                             Normally  you  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 alter the way  curl
                             behaves.  So  for  example  if you want to make a
                             proper HEAD request, using -X HEAD does not  suf-
                             fice. You need to use the -I, --head option.

                             The  method  string you set with -X, --request is
                             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 similar.

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

              POP3           Specifies a custom POP3 command to use instead of
                             LIST or RETR.

              IMAP           Specifies a custom IMAP command to use instead of
                             LIST.

              SMTP           Specifies a custom SMTP command to use instead of
                             HELP or VRFY.

              If -X, --request is provided several times, the last  set  value
              is 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 normally resolved address to
              be used. Consider it a sort of /etc/hosts  alternative  provided
              on  the  command line. The port number should be the number used
              for the specific protocol the host is 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  is
              used first.

              The  provided  address  set  by  this option is 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  default  timeout  (1 minute). Note that this only
              makes sense for long running parallel transfers with  a  lot  of
              files.  In  such  cases,  if  this  option is used curl tries 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.

              --resolve can be used several times in a command line

              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  (for  example in your 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 redirected 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 option,  since  you
              may receive duplicate data.

              By default curl does not return error for transfers with an HTTP
              response code that indicates an HTTP error, 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 retries on some HTTP response codes
              that indicate transient HTTP errors, 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 com-
              bine with -f, --fail.

              Providing --retry-all-errors multiple times has no extra effect.
              Disable it again with --no-retry-all-errors.

              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.

              Providing  --retry-connrefused  multiple  times  has  no   extra
              effect.  Disable it again with --no-retry-connrefused.

              Example:
               curl --retry-connrefused --retry 7 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 retries). This option is
              only interesting if --retry is also used. Setting this delay  to
              zero makes curl use the default backoff time.

              If  --retry-delay  is provided several times, the last set value
              is used.

              Example:
               curl --retry-delay 5 --retry 7 https://example.com

              See also --retry.

       --retry-max-time <seconds>
              The retry timer is reset  before  the  first  transfer  attempt.
              Retries are 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 is made and while performing, it
              may take longer than this given time period. To limit  a  single
              request's  maximum  time, use -m, --max-time. Set this option to
              zero to not timeout retries.

              If --retry-max-time is provided  several  times,  the  last  set
              value is 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 retries this number of times before giving up. Set-
              ting  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 first waits one  sec-
              ond  and then for all forthcoming retries it doubles the waiting
              time until it  reaches  10  minutes  which  then  remains  delay
              between the rest of the retries. By using --retry-delay you dis-
              able   this   exponential   backoff    algorithm.    See    also
              --retry-max-time to limit the total time allowed for retries.

              curl  complies  with the Retry-After: response header if one was
              present to know when to issue the next retry (added in 7.66.0).

              If --retry is provided several times,  the  last  set  value  is
              used.

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

              See also --retry-max-time.

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

              If  the  option is not specified, the server derives the authzid
              from the authcid, 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.

              If  --sasl-authzid is provided several times, the last set value
              is used.

              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.

              Providing --sasl-ir multiple times has no extra effect.  Disable
              it again with --no-sasl-ir.

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

              See also --sasl-authzid.

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

              If  --service-name is provided several times, the last set value
              is used.

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

              See also --negotiate and --proxy-service-name.

       -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.

              Providing -S, --show-error multiple times has no  extra  effect.
              Disable it again with --no-show-error.

              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 mes-
              sages. Makes Curl mute. It still outputs the data you  ask  for,
              potentially even to the terminal/stdout unless you redirect it.

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

              Providing -s, --silent multiple times has no extra effect.  Dis-
              able it again with --no-silent.

              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 speci-
              fied, it is assumed at port 1080. Using this  socket  type  make
              curl  resolve  the  host  name and passing the address on to the
              proxy.

              To specify proxy on a unix  domain  socket,  use  localhost  for
              host, e.g.  socks4://localhost/path/to/socket.sock

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

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

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

              If --socks4 is provided several times, the  last  set  value  is
              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 spec-
              ified, it is assumed at  port  1080.  This  asks  the  proxy  to
              resolve the host name.

              To  specify  proxy  on  a  unix domain socket, use localhost for
              host, e.g.  socks4a://localhost/path/to/socket.sock

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

              This option is superfluous since you can specify a socks4a proxy
              with -x, --proxy using a socks4a:// protocol prefix.

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

              If  --socks4a  is  provided several times, the last set value is
              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 connect-
              ing  to a SOCKS5 proxy.  The username/password authentication is
              enabled  by  default.   Use  --socks5-gssapi  to  force  GSS-API
              authentication to SOCKS5 proxies.

              Providing --socks5-basic multiple times has no extra effect.

              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 negoti-
              ated. RFC 1961 says in section 4.3/4.4 it should  be  protected,
              but  the  NEC  reference  implementation  does  not.  The option
              --socks5-gssapi-nec allows the unprotected exchange of the  pro-
              tection mode negotiation.

              Providing   --socks5-gssapi-nec  multiple  times  has  no  extra
              effect.  Disable it again with --no-socks5-gssapi-nec.

              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.

              If  --socks5-gssapi-service  is provided several times, the last
              set value is used.

              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 support).  Use  --socks5-basic
              to force username/password authentication to SOCKS5 proxies.

              Providing  --socks5-gssapi  multiple  times has no extra effect.
              Disable it again with --no-socks5-gssapi.

              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.

              To specify proxy on a unix  domain  socket,  use  localhost  for
              host, e.g.  socks5h://localhost/path/to/socket.sock

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

              This option is superfluous since you can specify a socks5  host-
              name proxy with -x, --proxy using a socks5h:// protocol prefix.

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

              If --socks5-hostname is provided several  times,  the  last  set
              value is 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.

              To  specify  proxy  on  a  unix domain socket, use localhost for
              host, e.g.  socks5://localhost/path/to/socket.sock

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

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

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

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

              If --socks5 is provided several times, the  last  set  value  is
              used.

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

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

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

              If  -Y,  --speed-limit  is  provided several times, the last set
              value is 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 transfer runs slower than speed-limit bytes per second dur-
              ing  a speed-time period, the transfer is aborted. If speed-time
              is used, the default  speed-limit  is  1  unless  set  with  -Y,
              --speed-limit.

              This option controls transfers (in both directions) but does not
              affect slow connects etc. If this is a concern for you, try  the
              --connect-timeout option.

              If  -y,  --speed-time  is  provided  several times, the last set
              value is 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 workarounds known to cause  interop-
              erability problems with some older SSL implementations.

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

              Providing --ssl-allow-beast multiple times has no extra  effect.
              Disable it again with --no-ssl-allow-beast.

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

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

       --ssl-auto-client-cert
              (Schannel) Tell libcurl to automatically locate and use a client
              certificate for authentication, when requested  by  the  server.
              Since  the  server  can  request  any  certificate that supports
              client authentication in the OS certificate store it could be  a
              privacy violation and unexpected.

              Providing  --ssl-auto-client-cert  multiple  times  has no extra
              effect.  Disable it again with --no-ssl-auto-client-cert.

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

              Providing --ssl-no-revoke multiple times has  no  extra  effect.
              Disable it again with --no-ssl-no-revoke.

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

              See also --crlfile.

       --ssl-reqd
              (FTP  IMAP  POP3  SMTP LDAP) Require SSL/TLS for the connection.
              Terminates the connection if the transfer cannot be upgraded  to
              use SSL/TLS.

              This  option  is  handled in LDAP (added in 7.81.0). It is fully
              supported by the OpenLDAP backend and rejected  by  the  generic
              ldap backend if explicit TLS is required.

              This  option  is  unnecessary  if  you  use a URL scheme that in
              itself implies immediate and implicit use of TLS, like for FTPS,
              IMAPS,  POP3S,  SMTPS and LDAPS. Such a transfer always fails if
              the TLS handshake does not work.

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

              Providing --ssl-reqd multiple times has no extra  effect.   Dis-
              able it again with --no-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 revoca-
              tion checks when they failed due to missing/offline distribution
              points for the revocation check lists.

              Providing  --ssl-revoke-best-effort  multiple times has no extra
              effect.  Disable it again with --no-ssl-revoke-best-effort.

              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) Warning: this is considered  an  inse-
              cure  option.  Consider using --ssl-reqd instead to be sure curl
              upgrades to a secure connection.

              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-control and --ssl-reqd for different levels of encryp-
              tion required.

              This  option  is  handled in LDAP (added in 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 nego-
              tiation does not succeed.

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

              Providing  --ssl multiple times has no extra effect.  Disable it
              again with --no-ssl.

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

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

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

              Providing -2, --sslv2 multiple times has no extra effect.

              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 is
              mutually exclusive to -3, --sslv3 and -1, --tlsv1 and  --tlsv1.1
              and --tlsv1.2.

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

              Providing -3, --sslv3 multiple times has no extra effect.

              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  is
              mutually  exclusive to -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 --stderr is provided several times, the  last  set  value  is
              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 terminal. Use --no-styled-output to  switch  them
              off.

              Styled output requires a terminal that supports bold fonts. This
              feature is not present on curl for Windows due to lack  of  this
              capability.

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

              Providing --styled-output multiple times has  no  extra  effect.
              Disable it again with --no-styled-output.

              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 effect on
              debug  options  such as -v, --verbose or --trace, or any statis-
              tics.

              Providing --suppress-connect-headers multiple times has no extra
              effect.  Disable it again with --no-suppress-connect-headers.

              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 (RFC 7413). TCP Fast Open is  a  TCP
              extension  that allows data to get sent earlier over the connec-
              tion (before the final handshake ACK) if the client  and  server
              have been connected previously.

              Providing  --tcp-fastopen  multiple  times  has no extra effect.
              Disable it again with --no-tcp-fastopen.

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

              See also --false-start.

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

              curl  sets  this  option  by  default and you need to explicitly
              switch it off if you do not want it on (added in 7.50.2).

              Providing --tcp-nodelay multiple  times  has  no  extra  effect.
              Disable it again with --no-tcp-nodelay.

              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.

              -t, --telnet-option can be used several times in a command line

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

              See also -K, --config.

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

              If  --tftp-blksize is provided several times, the last set value
              is 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 ignored.

              Providing --tftp-no-options multiple times has no extra  effect.
              Disable it again with --no-tftp-no-options.

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

              See also --tftp-blksize.

       -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  file-
              name  and tries to get the modification date (mtime) from <file>
              instead. See the curl_getdate(3) man pages for  date  expression
              details.

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

              If  provided  a  non-existing file, curl outputs a warning about
              that fact and proceeds to do the transfer without a time  condi-
              tion.

              If -z, --time-cond is provided several times, the last set value
              is 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>
              (TLS) 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.

              If  --tls-max  is  provided several times, the last set value is
              used.

              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 underlying libcurl was built to sup-
              port 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 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, or Schannel. If you are using a  differ-
              ent  SSL  backend  you  can try setting TLS 1.3 cipher suites by
              using the --ciphers option.

              If --tls13-ciphers is provided several times, the last set value
              is used.

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

              See also --ciphers, --curves and --proxy-tls13-ciphers. 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.

              If  --tlsauthtype  is provided several times, the last set value
              is used.

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

              See also --tlsuser.

       --tlspassword <string>
              Set password for use with the TLS authentication  method  speci-
              fied with --tlsauthtype. Requires that --tlsuser also be set.

              This option does not work with TLS 1.3.

              If  --tlspassword  is provided several times, the last set value
              is used.

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

              See also --tlsuser.

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

              This option does not work with TLS 1.3.

              If --tlsuser is provided several times, the last  set  value  is
              used.

              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 connect-
              ing 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 ver-
              sion.

              Providing --tlsv1.0 multiple times has no extra effect.

              Example:
               curl --tlsv1.0 https://example.com

              See also --tlsv1.3.

       --tlsv1.1
              (TLS)  Forces curl to use TLS version 1.1 or later when connect-
              ing 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 ver-
              sion.

              Providing --tlsv1.1 multiple times has no extra effect.

              Example:
               curl --tlsv1.1 https://example.com

              See also --tlsv1.3 and --tls-max.

       --tlsv1.2
              (TLS)  Forces curl to use TLS version 1.2 or later when connect-
              ing 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 ver-
              sion.

              Providing --tlsv1.2 multiple times has no extra effect.

              Example:
               curl --tlsv1.2 https://example.com

              See also --tlsv1.3 and --tls-max.

       --tlsv1.3
              (TLS)  Forces curl to use TLS version 1.3 or later when connect-
              ing 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.

              Providing --tlsv1.3 multiple times has no extra effect.

              Example:
               curl --tlsv1.3 https://example.com

              See also --tlsv1.2 and --tls-max. Added in 7.52.0.

       -1, --tlsv1
              (TLS)  Tells curl to use at least TLS version 1.x when negotiat-
              ing with a remote TLS server. That  means  TLS  version  1.0  or
              higher

              Providing -1, --tlsv1 multiple times has no extra effect.

              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  is
              mutually exclusive to --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.

              Providing  --tr-encoding  multiple  times  has  no extra effect.
              Disable it again with --no-tr-encoding.

              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 untrained humans.

              Note that verbose output of curl activities and network  traffic
              might  contain sensitive data, including user names, credentials
              or secret data content. Be aware and  be  careful  when  sharing
              trace logs with others.

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

              If --trace-ascii is provided several times, the last  set  value
              is used.

              Example:
               curl --trace-ascii log.txt https://example.com

              See  also  -v,  --verbose  and  --trace. This option is mutually
              exclusive to --trace and -v, --verbose.

       --trace-config <string>
              Set configuration for trace output. A  comma-separated  list  of
              components  where  detailed  output  can be made available from.
              Names are case-insensitive.  Specify 'all' to enable  all  trace
              components.

              In  addition  to trace component names, specify "ids" and "time"
              to avoid extra --trace-ids or --trace-time parameters.

              See the curl_global_trace(3) man page for more details.

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

              --trace-config can be used several times in a command line

              Example:
               curl --trace-config ids,http/2 https://example.com

              See  also  -v,  --verbose  and  --trace. This option is mutually
              exclusive to --trace and -v, --verbose. Added in 8.3.0.

       --trace-ids
              Prepends the transfer and connection identifiers 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.

              Providing --trace-ids multiple times has no extra effect.   Dis-
              able it again with --no-trace-ids.

              Example:
               curl --trace-ids --trace-ascii output https://example.com

              See also --trace and -v, --verbose. Added in 8.2.0.

       --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.

              Providing --trace-time multiple times has no extra effect.  Dis-
              able it again with --no-trace-time.

              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.

              Note  that verbose output of curl activities and network traffic
              might contain sensitive data, including user names,  credentials
              or  secret  data  content.  Be aware and be careful when sharing
              trace logs with others.

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

              If  --trace  is  provided  several  times, the last set value is
              used.

              Example:
               curl --trace log.txt https://example.com

              See  also   --trace-ascii,   --trace-config,   --trace-ids   and
              --trace-time. This option is mutually exclusive to -v, --verbose
              and --trace-ascii.

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

              If  --unix-socket  is provided several times, the last set value
              is used.

              Example:
               curl --unix-socket socket-path https://example.com

              See also --abstract-unix-socket.

       -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 appends  the
              local  file  name  to  the  end  of the URL before the operation
              starts. You must use a trailing slash (/) on the last  directory
              to  prove to curl that there is no file name or curl thinks that
              your last directory name is the remote file name to use.

              When putting the local file name at the end  of  the  URL,  curl
              ignores  what  is on the left side of any slash (/) or backslash
              (\) used in the file name and only appends what is on the  right
              side of the rightmost such character.

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

              If  this  option  is  used with a HTTP(S) URL, the PUT method is
              used.

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

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

              -T, --upload-file can be used several times in a command line

              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, -I, --head, -X, --request and -d, --data.

       --url-query <data>
              (all) This option adds a piece of data, usually a name  +  value
              pair,  to the end of the URL query part. The syntax is identical
              to that used for --data-urlencode with one extension:

              If the argument starts with a '+' (plus), the rest of the string
              is provided as-is unencoded.

              The  query  part of a URL is the one following the question mark
              on the right end.

              --url-query can be used several times in a command line

              Examples:
               curl --url-query name=val https://example.com
               curl --url-query =encodethis http://example.net/foo
               curl --url-query name@file https://example.com
               curl --url-query @fileonly https://example.com
               curl --url-query "+name=%20foo" https://example.com

              See also --data-urlencode and -G, --get. Added in 7.87.0.

       --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 makes a guess based on the host. If  the
              outermost  subdomain name matches DICT, FTP, IMAP, LDAP, POP3 or
              SMTP then that protocol is used, otherwise HTTP is used.  Guess-
              ing can be avoided by providing a full URL including the scheme,
              or disabled by setting a default protocol (added in 7.45.0), see
              --proto-default for details.

              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  con-
              verted to network accesses by the operating system. Beware!

              --url can be used several times in a command line

              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.

              Providing  -B,  --use-ascii  multiple times has no extra effect.
              Disable it again with --no-use-ascii.

              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
              removes the header completely from the request. If you prefer  a
              blank header, you can set it to a single space (" ").

              If  -A,  --user-agent  is  provided  several times, the last set
              value is 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 authentica-
              tion. Overrides -n, --netrc and --netrc-optional.

              If  you  simply  specify the user name, curl prompts for a pass-
              word.

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

              On systems where it works, curl hides 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  still  are visible for a brief moment before cleared. Such
              sensitive data should be retrieved from a file instead or  simi-
              lar 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 Kerberos 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@example.com respectively.

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

              If  -u,  --user is provided several times, the last set value is
              used.

              Example:
               curl -u user:secret https://example.com

              See also -n, --netrc and -K, --config.

       --variable <[%]name=text/@file>
              Set a variable with "name=content" or "name@file" (where  "file"
              can  be  stdin  if set to a single dash (-)). The name is a case
              sensitive identifier that must consist of no other letters  than
              a-z, A-Z, 0-9 or underscore. The specified content is then asso-
              ciated with this identifier.

              Setting the same variable name again overwrites the old contents
              with the new.

              The  contents of a variable can be referenced in a later command
              line option when that option name is prefixed with  "--expand-",
              and the name is used as "{{name}}" (without the quotes).

              --variable can import environment variables into the name space.
              Opt to either require the environment variable to be set or pro-
              vide  a default value for the variable in case it is not already
              set.

              --variable %name imports the variable called  'name'  but  exits
              with  an  error if that environment variable is not already set.
              To provide a default value if the environment  variable  is  not
              set,  use  --variable %name=content or --variable %name@content.
              Note that on some systems - but not all - environment  variables
              are case insensitive.

              When  expanding variables, curl supports a set of functions that
              can make the variable contents more convenient to use. You apply
              a  function  to  a variable expansion by adding a colon and then
              list the desired functions in a  comma-separated  list  that  is
              evaluated  in  a  left-to-right  order. Variable content holding
              null bytes that are not encoded when expanded, causes an error.

              Available functions:

              trim           removes all leading and trailing white space.

              json           outputs the content  using  JSON  string  quoting
                             rules.

              url            shows the content URL (percent) encoded.

              b64            expands the variable base64 encoded

              --variable can be used several times in a command line

              Example:
               curl --variable name=smith https://example.com

              See also -K, --config. Added in 8.3.0.

       -v, --verbose
              Makes  curl  verbose  during the operation. Useful for debugging
              and seeing what's going on "under the  hood".  A  line  starting
              with  '>'  means  "header  data" sent by curl, '<' means "header
              data" received by curl that is hidden in  normal  cases,  and  a
              line starting with '*' means additional info provided by curl.

              If  you  only  want HTTP headers in the output, -i, --include or
              -D, --dump-header might be more suitable options.

              If you think this option still does not give you enough details,
              consider using --trace or --trace-ascii instead.

              Note  that verbose output of curl activities and network traffic
              might contain sensitive data, including user names,  credentials
              or  secret  data  content.  Be aware and be careful when sharing
              trace logs with others.

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

              Providing  -v,  --verbose  multiple  times  has no extra effect.
              Disable it again with --no-verbose.

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

              See also -i, --include, -s, --silent, --trace and --trace-ascii.
              This option is mutually exclusive to --trace and --trace-ascii.

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

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

              The second line (starts with "Release-Date:") shows the  release
              date.

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

              The fourth line (starts with "Features:")  shows  specific  fea-
              tures 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 because 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  suf-
                     fixes".

              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 supported.

              Example:
               curl --version

              See also -h, --help and -M, --manual.

       -w, --write-out <format>
              Make curl display information on stdout after a completed trans-
              fer.  The  format  is a string that may contain plain text mixed
              with any number of variables. The format can be specified  as  a
              literal  "string",  or  you can have curl read the format from a
              file with "@filename" and to tell curl to read the  format  from
              stdin you write "@-".

              The  variables  present  in the output format are substituted by
              the value or text that curl thinks fit, as described below.  All
              variables are specified as %{variable_name} and to output a nor-
              mal % 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 is by default written to standard output, but can be
              changed with %{stderr} and %output{}.

              Output HTTP headers  from  the  most  recent  request  by  using
              %header{name}  where  name  is  the case insensitive name of the
              header (without the trailing colon).  The  header  contents  are
              exactly  as  sent  over  the  network, with leading and trailing
              whitespace trimmed (added in 7.84.0).

              Select a specific target destination file to  write  the  output
              to,  by  using %output{name} (added in curl 8.3.0) where name is
              the full file name. The output  following  that  instruction  is
              then  written  to that file. More than one %output{} instruction
              can be specified in the same write-out  argument.  If  the  file
              name  cannot  be  created, curl leaves the output destination to
              the one used prior  to  the  %output{}  instruction.  Use  %out-
              put{>>name} to append data to an existing file.

              NOTE: In Windows the %-symbol is a special symbol used to expand
              environment variables. In batch files all occurrences of %  must
              be  doubled  when  using this option to properly escape. If this
              option is used at the  command  prompt  then  the  %  cannot  be
              escaped and unintended expansion is possible.

              The variables available are:

              certs          Output  the  certificate chain with details. Sup-
                             ported only by the OpenSSL, GnuTLS, Schannel  and
                             Secure Transport backends. (Added in 7.88.0)

              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 exit code of the  transfer.  (Added
                             in 7.75.0)

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

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

              header_json    A JSON object with all HTTP response headers from
                             the  recent  transfer.  Values  are  provided  as
                             arrays, since in the  case  of  multiple  headers
                             there can be multiple values. (Added in 7.83.0)

                             The header names provided in lowercase, listed in
                             order of appearance over  the  wire.  Except  for
                             duplicated headers. They are grouped on the first
                             occurrence of that header,  each  value  is  pre-
                             sented in the JSON array.

              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_certs      Number of server certificates received in the TLS
                             handshake. Supported only by the OpenSSL, GnuTLS,
                             Schannel  and  Secure Transport backends.  (Added
                             in 7.88.0)

              num_connects   Number of new connects made in the recent  trans-
                             fer.

              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 certifi-
                             cate verification that was requested. 0 means the
                             verification was successful. (Added in 7.52.0)

              redirect_url   When an HTTP request was made without -L, --loca-
                             tion to follow redirects (or when --max-redirs is
                             met),  this variable shows the actual URL a redi-
                             rect 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 trans-
                             ferred, excluding headers.

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

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

              size_upload    The  total  amount  of  bytes that were uploaded.
                             This is the size of the body/data that was trans-
                             ferred, excluding headers.

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

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

              ssl_verify_result
                             The  result of the SSL peer certificate verifica-
                             tion that was requested. 0 means the verification
                             was successful.

              stderr         From this point on, the -w, --write-out output is
                             written to standard error. (Added in 7.63.0)

              stdout         From this point on, the -w, --write-out output is
                             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 resolving was completed.

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

              time_redirect  The time, in seconds, it took for all redirection
                             steps including name lookup, connect, pretransfer
                             and transfer before  the  final  transaction  was
                             started.  time_redirect shows the complete execu-
                             tion time for multiple redirections.

              time_starttransfer
                             The time, in seconds,  it  took  from  the  start
                             until  the first byte is received.  This includes
                             time_pretransfer and also  the  time  the  server
                             needed to calculate the result.

              time_total     The  total time, in seconds, that the full opera-
                             tion lasted.

              url            The URL that was fetched. (Added in 7.75.0)

              url.scheme     The scheme part of  the  URL  that  was  fetched.
                             (Added in 8.1.0)

              url.user       The user part of the URL that was fetched. (Added
                             in 8.1.0)

              url.password   The password part of the URL  that  was  fetched.
                             (Added in 8.1.0)

              url.options    The  options  part  of  the URL that was fetched.
                             (Added in 8.1.0)

              url.host       The host part of the URL that was fetched. (Added
                             in 8.1.0)

              url.port       The  port  number of the URL that was fetched. If
                             no port number was specified, but the URL  scheme
                             is  known,  that  scheme's default port number is
                             shown. (Added in 8.1.0)

              url.path       The path part of the URL that was fetched. (Added
                             in 8.1.0)

              url.query      The  query  part  of  the  URL  that was fetched.
                             (Added in 8.1.0)

              url.fragment   The fragment part of the URL  that  was  fetched.
                             (Added in 8.1.0)

              url.zoneid     The  zone  id  part  of the URL that was fetched.
                             (Added in 8.1.0)

              urle.scheme    The scheme part of the effective (last) URL  that
                             was fetched. (Added in 8.1.0)

              urle.user      The  user  part  of the effective (last) URL that
                             was fetched. (Added in 8.1.0)

              urle.password  The password part of  the  effective  (last)  URL
                             that was fetched. (Added in 8.1.0)

              urle.options   The options part of the effective (last) URL that
                             was fetched. (Added in 8.1.0)

              urle.host      The host part of the effective  (last)  URL  that
                             was fetched. (Added in 8.1.0)

              urle.port      The  port number of the effective (last) URL that
                             was fetched. If no port number was specified, but
                             the  URL  scheme  is known, that scheme's default
                             port number is shown. (Added in 8.1.0)

              urle.path      The path part of the effective  (last)  URL  that
                             was fetched. (Added in 8.1.0)

              urle.query     The  query  part of the effective (last) URL that
                             was fetched. (Added in 8.1.0)

              urle.fragment  The fragment part of  the  effective  (last)  URL
                             that was fetched. (Added in 8.1.0)

              urle.zoneid    The zone id part of the effective (last) URL that
                             was fetched. (Added in 8.1.0)

              urlnum         The URL index number of this transfer, 0-indexed.
                             Unglobbed 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 mean-
                             ingful  if you have told curl to follow location:
                             headers.

              If -w, --write-out is provided several times, the last set value
              is used.

              Example:
               curl -w '%{response_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 attribute and, for HTTP,
              the content type is stored in the mime_type  attribute.  If  the
              file  system  does not support extended attributes, a warning is
              issued.

              Providing --xattr multiple times has no extra  effect.   Disable
              it again with --no-xattr.

              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  pro-
              tocol  is  a  protocol  that curl supports and as specified in a
              URL. FTP, FTPS, POP3, IMAP, SMTP, LDAP, etc.

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

       NO_PROXY <comma-separated list of hosts/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 host-
              name, 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.example.com
              http://direct.example.com  accesses the target URL directly, and
              NO_PROXY=direct.example.com  curl  -x   http://proxy.example.com
              http://somewhere.example.com accesses the target URL through the
              proxy.

              The list  of  host  names  can  also  be  include  numerical  IP
              addresses,  and  IPv6  versions  should  then  be  given without
              enclosing brackets.

              IP addresses can be specified using CIDR notation:  an  appended
              slash  and  number specifies the number of "network bits" out of
              the address to use in the  comparison  (added  in  7.86.0).  For
              example "192.168.0.0/16" would match all addresses starting with
              "192.168".

       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 is used as the termi-
              nal width when the alternative progress-bar  is  shown.  If  not
              set, curl tries to figure it out using other ways.

       CURL_CA_BUNDLE <file>
              If set, it is 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_CON-
              FIG_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  envi-
              ronment  variable can be set to the case insensitive name of the
              particular backend to use when curl is invoked. Setting  a  name
              that  is  not  a  built-in  alternative makes curl stay with the
              default.

              SSL backend names (case-insensitive): bearssl, gnutls,  mbedtls,
              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 makes curl produce qlogs  in  that
              directory,  using file names named after the destination connec-
              tion id (in hex). Do note that these  files  can  become  rather
              large. Works with the ngtcp2 and quiche QUIC backends.

       SHELL  Used  on  VMS  when  trying  to  detect if using a DCL or a unix
              shell.

       SSL_CERT_DIR <dir>
              If set, it is used as the --capath value.

       SSL_CERT_FILE <path>
              If set, it is used as the --cacert value.

       SSLKEYLOGFILE <file name>
              If you set this environment variable to a file name, curl stores
              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 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 uses the path "$USERPROFILE\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 supported one, the proxy is 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 pre-
              fix 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:

       0      Success. The operation completed successfully according  to  the
              instructions.

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

       2      Failed to initialize.

       3      URL malformed. The syntax was not correct.

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

       5      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 resource or directory you wanted to  reach.  Most
              often  you tried to change to a directory 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 simi-
              lar) command failed.

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

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

       23     Write  error. Curl 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 uploading.

       26     Read error. Various reading problems.

       27     Out of memory. A memory allocation request failed.

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

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

       31     FTP 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 down-
              load.

       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 oper-
              ation.

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

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

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

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

       49     Malformed telnet option.

       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  certifi-
              cates.

       61     Unrecognized transfer encoding.

       63     Maximum file size exceeded.

       64     Requested FTP SSL level failed.

       65     Sending the data requires a rewind that failed.

       66     Failed to initialize 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).

       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 is 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.

       97     Proxy handshake error.

       98     A  client-side certificate is required to complete the TLS hand-
              shake.

       99     Poll or select returned fatal error.

       XX     More error codes might  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 8.4.0                      October 05 2023                        curl(1)

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