curl(1) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | URL | OUTPUT | PROTOCOLS | PROGRESS METER | VERSION | OPTIONS | FILES | ENVIRONMENT | PROXY PROTOCOL PREFIXES | EXIT CODES | BUGS | AUTHORS / CONTRIBUTORS | WWW | SEE ALSO | COLOPHON

curl(1)                        curl Manual                       curl(1)

NAME         top

       curl - transfer a URL

SYNOPSIS         top

       curl [options / URLs]

DESCRIPTION         top

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

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

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

URL         top

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

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

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

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

         "ftp://ftp.example.com/file[1-100].txt"

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

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

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

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

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

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

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

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

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

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

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

       If you specify a URL without a 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.

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

OUTPUT         top

       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         top

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

       DICT   Lets you lookup words using online dictionaries.

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

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

       GOPHER(S)
              Retrieve files.

       HTTP(S)
              curl supports HTTP with numerous options and variations.
              It can speak HTTP version 0.9, 1.0, 1.1, 2 and 3 depending
              on build options and the correct command line 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
              "subscribe" to a topic while uploading/posting equals
              "publish" on a topic. MQTT over TLS is not supported
              (yet).

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

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

       RTSP   curl supports RTSP 1.0 downloads.

       SCP    curl supports SSH version 2 scp transfers.

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

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

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

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

       TFTP   curl can do TFTP downloads and uploads.

PROGRESS METER         top

       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         top

       This man page describes curl 8.2.0. 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

OPTIONS         top

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

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

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

       In general, all boolean options are enabled with --option and yet
       again disabled with --no-option. That is, you use the same option
       name but prefix it with "no-". However, in this list we mostly
       only list and show the --option version of them.

       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 will retain their values and meaning
       even after -:, --next.

       The following options are global: --fail-early, --libcurl,
       --parallel-immediate, -Z, --parallel, -#, --progress-bar, --rate,
       -S, --show-error, --stderr, --styled-output, --trace-ascii,
       --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 will be 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 will be used. After a completed transfer, the cache
              will be saved to the file name again if it has been
              modified.

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

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

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

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

              Used together with -u, --user.

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

              Providing -a, --append multiple times has no extra effect.
              Disable 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
              provided 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 will be 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 will
              otherwise use a CA store provided in a single file or
              directory, but when using this option it will interface
              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.

              Providing --ca-native multiple times has no extra effect.
              Disable 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 will automatically look for a
              CA certs file named 'curl-ca-bundle.crt', either in the
              same directory as curl.exe, or in the Current Working
              Directory, or in any folder along your PATH.

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

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

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

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

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

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

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

              If this option is set, the default capath value will be
              ignored.

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

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

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

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

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

              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. Added in 7.41.0.

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

              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 will be used.

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

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

       -E, --cert <certificate[:password]>
              (TLS) Tells curl to use the specified client certificate
              file when getting a file with HTTPS, FTPS or another SSL-
              based protocol. The certificate must be in PKCS#12 format
              if using Secure Transport, or PEM format if using any
              other engine. If the optional password is not specified,
              it will be queried for on the terminal. Note that this
              option assumes a certificate file that is the private key
              and the client certificate concatenated. See -E, --cert
              and --key to specify them 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 the NSS SSL library then this
              option can tell curl the nickname of the certificate to
              use within the NSS database defined by the environment
              variable SSL_DIR (or by default /etc/pki/nssdb). If the
              NSS PEM PKCS#11 module (libnsspem.so) is available then
              PEM files may be loaded.

              If you provide a path relative to the current directory,
              you must prefix the path with "./" in order to avoid
              confusion with an NSS database nickname.

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

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

              (Schannel only) Client certificates must be specified by a
              path expression to a certificate store. (Loading PFX is
              not supported; you can import it to a store first). You
              can use "<store location>\<store name>\<thumbprint>" to
              refer to a certificate in the system certificates store,
              for example,
              "CurrentUser\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,
              LocalMachineEnterprise.

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

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

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

       --ciphers <list of ciphers>
              (TLS) Specifies which ciphers to use in the connection.
              The list of ciphers must specify valid ciphers. Read up on
              SSL cipher list details on this URL:

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

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

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

              See also --tlsv1.3.

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

              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 will report 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.
              Disable 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 will be used
              as if they were provided on the command line.

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

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

              If the first column of a config line is a '#' character,
              the rest of the line will be treated as a comment.

              Only write one option per physical line in the config
              file.

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

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

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

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

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

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

              1) "$CURL_HOME/.curlrc"

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

              3) "$HOME/.curlrc"

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

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

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

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

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

              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 connects within the given period it will continue -
              if not it will exit.  Since version 7.32.0, this option
              accepts decimal values.

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

              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 --connect-timeout is provided several times, the last
              set value will be used.

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

              See also -m, --max-time.

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

              For a request to the given HOST1:PORT1 pair, connect to
              HOST2:PORT2 instead.  This option is suitable to direct
              requests at a specific server, e.g. at a specific cluster
              node in a cluster of servers. This option is only used to
              establish the network connection. It does NOT affect the
              hostname/port that is used for TLS/SSL (e.g. SNI,
              certificate verification) or for the application
              protocols. "HOST1" and "PORT1" may be the empty string,
              meaning "any host/port". "HOST2" and "PORT2" may also be
              the empty string, meaning "use the request's original
              host/port".

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

              --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. Added in 7.49.0.

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

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

              If -C, --continue-at is provided several times, the last
              set value will be used.

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

              See also -r, --range.

       -c, --cookie-jar <filename>
              (HTTP) Specify to which file you want curl to write all
              cookies after a completed operation. Curl writes all
              cookies from its in-memory cookie storage to the given
              file at the end of operations. If no cookies are known, no
              data will be written. The file will be written using the
              Netscape cookie file format. If you set the file name to a
              single dash, "-", the cookies will be written to stdout.

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

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

              If -c, --cookie-jar is provided several times, the last
              set value will be used.

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

              See also -b, --cookie.

       -b, --cookie <data|filename>
              (HTTP) Pass the data to the HTTP server in the Cookie
              header. It is supposedly the data previously received from
              the server in a "Set-Cookie:" line. The data should be in
              the format "NAME1=VALUE1; NAME2=VALUE2". 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 will
              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
              will make curl record incoming cookies, which may be handy
              if you are using this in combination with the -L,
              --location option or do multiple URL transfers on the same
              invoke. If the file name is exactly a minus ("-"), curl
              will instead read the contents from stdin.

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

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

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

              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 will create the necessary local directory hierarchy
              as needed. This option creates the directories mentioned
              with the -o, --output option, nothing else. If the -o,
              --output file name uses no directory, or if the
              directories it mentions already exist, no directories will
              be created.

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

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

              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 will be used.

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

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

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

              (SMTP added in 7.40.0)

              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
              Revocation List that may specify peer certificates that
              are to be considered revoked.

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

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

              See also --cacert and --capath.

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

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

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

              If --curves is provided several times, the last set value
              will be 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
              processing whatsoever.

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

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

              If this option is used several times, the ones following
              the first will 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. Added in 7.43.0.

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

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

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

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

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

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

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

              --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 will cause curl to pass the data to the
              server using the content-type application/x-www-form-
              urlencoded. Compare to -F, --form.

              --data-raw is almost the same but does not have a special
              interpretation 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
              command line, the data pieces specified will be merged
              with a separating &-symbol. Thus, using '-d name=daniel -d
              skill=lousy' would generate a post chunk that looks like
              'name=daniel&skill=lousy'.

              If you start the data with the letter @, the rest should
              be a file name to read the data from, or - if you want
              curl to read the data from stdin. Posting data from a file
              named 'foobar' would thus be done with -d, --data @foobar.
              When -d, --data is told to read from a file like that,
              carriage returns and newlines will be stripped out. If you
              do not want the @ character to have a special
              interpretation use --data-raw instead.

              The data for this option is passed on to the server
              exactly as provided on the command line. curl will not
              convert it, change it or improve it. It is up to the user
              to provide the data in the correct 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 will be used.

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

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

       --digest
              (HTTP) Enables HTTP Digest authentication. This is an
              authentication scheme that prevents the password from
              being sent over the wire in clear text. Use this in
              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 will
              normally always first attempt to use EPRT, then LPRT
              before using PORT, but with this option, it will use PORT
              right away. EPRT and LPRT are extensions to the original
              FTP protocol, and may not work on all servers, but they
              enable more functionality in a better way than the
              traditional PORT command.

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

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

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

              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 will normally
              always first attempt to use EPSV before PASV, but with
              this option, it will not try using EPSV.

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

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

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

              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 will not be read and used. See the -K,
              --config for details on the default config file search
              path.

              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
              <interface>. 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 will be 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. Added in 7.33.0.

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

              If --dns-ipv4-addr is provided several times, the last set
              value will be used.

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

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

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

              If --dns-ipv6-addr is provided several times, the last set
              value will be used.

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

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

       --dns-servers <addresses>
              Set the list of DNS servers to be used instead of the
              system default.  The list of IP addresses should be
              separated with commas. 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 will be used.

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

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

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

              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 will apply
              to DoH since the name lookups take place over SSL.
              However, the certificate verification settings are not
              inherited and can be controlled separately via --doh-
              insecure and --doh-cert-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
              will be used.

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

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

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

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

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

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

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

              See also -o, --output.

       --egd-file <file>
              (TLS) Deprecated option. This option is ignored by curl
              since 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 connections.

              If --egd-file is provided several times, the last set
              value will be 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
              operations. 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
              will be 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 specific ETag read from the given file by sending a
              custom If-None-Match header using the stored ETag.

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

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

              If --etag-compare is provided several times, the last set
              value will be 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 will be 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 will
              wait one second. This option accepts decimal values! When
              curl stops waiting, it will continue 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 will be used.

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

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

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

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

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

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

              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.
              Disable 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 will still allow curl to output and
              save that content but also to return error 22.

              This is an alternative option to -f, --fail which makes
              curl fail for the same 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. 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 will prevent curl from outputting that and return
              error 22.

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

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

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

              See also --fail-with-body. This option is mutually
              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 will
              start sending application data before verifying the
              server's Finished message, thus saving a round trip when
              performing a full handshake.

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

              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. Added in 7.42.0.

       --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 will be 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's any possibility that the string
              value may accidentally trigger 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
              emulate a filled-in form in which a user has pressed the
              submit button. This causes curl to POST data using the
              Content-Type multipart/form-data according to RFC 2388.

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

              This enables uploading of binary files etc. To force the
              'content' part to be a file, prefix the file name with an
              @ sign. To just get the content part from a file, prefix
              the file name with the symbol <. The difference between @
              and < is then that @ makes a file get attached in the post
              as a file upload, while the < makes a text field and just
              get the contents for that text field from a file.

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

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

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

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

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

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

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

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

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

              or

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

              Note that if a filename/path is quoted by double-quotes,
              any double-quote or 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
              multipart: 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
              consisting in an inline part in two alternative formats:
              plain text and HTML. It attaches a text file:

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

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

              Example: send multipart mail with a quoted-printable text
              message 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 will be used.

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

              See also -u, --user.

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

              If --ftp-alternative-to-user is provided several times,
              the last set value will be 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 will
              instead attempt 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 following alternatives:

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

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

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

              If --ftp-method is provided several times, the last set
              value will be 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 will try the EPSV command
              first and then PASV, unless --disable-epsv is used.

              Providing --ftp-pasv multiple times has no extra effect.
              Disable 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
              connecting with FTP. This option makes curl use active
              mode. curl then tells the server to connect back to the
              client's specified address and port, while passive mode
              asks the server to setup an IP address and port for it to
              connect to. <address> should be one of:

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

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

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

              -      make curl pick the same IP address that is already
                     used for the control 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 will be 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.
              Disable 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 will re-use the
              same IP address it already uses for the control
              connection.

              Since curl 7.74.0 this option is enabled by default.

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

              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 will not
              initiate the shutdown, but instead wait for the server to
              do it, and will not reply to the shutdown from the server.
              The active mode initiates the shutdown and waits for a
              reply from the server.

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

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

              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 letters 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 connection attempt is made to the IPv4
              address in parallel. The first connection to be
              established is the one that is used.

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

              If --happy-eyeballs-timeout-ms is provided several times,
              the last set value will be used.

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

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

       --haproxy-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 will be 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 will be 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.
              Disable 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, effectively 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 will be used instead of the internal one.  This
              allows you to make even trickier stuff than curl would
              normally do. You should not replace internally set headers
              without knowing perfectly well what you 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-Custom-
              Header;" to send "X-Custom-Header:".

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

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

              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, will make curl
              send the data using chunked encoding.

              WARNING: headers set with this option will be 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 commands of the <category>.  If
              no arg was provided, curl will display the most important
              command line arguments.  If the argument "all" was
              provided, curl will display all options available.  If the
              argument "category" was provided, curl will display all
              categories and their meanings.

              Example:
               curl --help all

              See also -v, --verbose.

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

              If --hostpubmd5 is provided several times, the last set
              value will be 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 will
              refuse 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 will be 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 will
              be used. After a completed transfer, the cache will be
              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 will load
              contents from all the files but the last one will be 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 completely headerless response and therefore
              you can also connect with this to non-HTTP servers and
              still get a response since curl will simply transparently
              downgrade - if allowed.

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

              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
              exclusive 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-knowledge and --http3. Added in 7.33.0.

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

              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. Added in 7.49.0.

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

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

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

              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 specification. 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.
              Added in 7.33.0.

       --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 will trigger 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 will make curl fail if a QUIC connection
              cannot be established, it will not attempt any other HTTP
              version 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 will issue a separate
              attempt to use older HTTP versions with a slight delay, so
              if the HTTP/3 transfer fails or is very slow, curl will
              still try 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
              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-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 will report incorrect Content-Length for files
              larger than 2 gigabytes.

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

              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
              verifies the server's TLS certificate before it continues:
              that the certificate contains the right name which matches
              the host name used in the URL and that the certificate has
              been signed by a CA certificate present in the cert store.
              See this online resource for further details:
               https://curl.se/docs/sslcerts.html

              For SFTP and SCP, this option makes curl skip the
              known_hosts verification.  known_hosts is a file normally
              stored in the user's home directory in the ".ssh"
              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 information about Linux VRF:
              https://www.kernel.org/doc/Documentation/networking/vrf.txt

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

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

              See also --dns-interface.

       -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
              exclusive 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
              exclusive 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 will be 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 will make it discard all "session
              cookies". This will basically have the same effect as if a
              new session is started. Typical browsers always discard
              session cookies when they are closed down.

              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 connections. 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 will be 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
              provided 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 will be used.

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

              See also --key.

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

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

              If 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
              will be used.

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

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

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

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

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

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

       --libcurl <file>
              Append this option to any ordinary curl command line, and
              you will get libcurl-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
              will be used.

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

              See also -v, --verbose.

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

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

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

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

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

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

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

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

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

              Note: When combined with -X, --request, this option can be
              used to send a UIDL 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 that will be busy
              at times 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 will be used.

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

              See also -g, --globoff.

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

              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 will make
              curl redo the request on the new place. If used together
              with -i, --include or -I, --head, headers from all
              requested pages will be shown. When authentication is
              used, curl only sends its credentials to the initial host.
              If a redirect takes curl to a different host, it will not
              be able to intercept the user+password. See also
              --location-trusted on how to change this. You can limit
              the amount of redirects to follow by using the --max-
              redirs option.

              When curl follows a redirect and if the request is a POST,
              it will send the following request with a GET if the HTTP
              response was 301, 302, or 303. If the response code was
              any other 3xx code, curl will re-send the following
              request using the same unmodified method.

              You can tell curl to not change 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 IETF draft draft-earhart-url-smtp-00.txt

              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 will send out your password in plain text. This will
              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 will be used.

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

              See also -u, --user. Added in 7.34.0.

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

              If --mail-auth is provided several times, the last set
              value will be 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 will be 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 will abort SMTP conversation if at least one
              of the recipients causes RCPT TO command to return an
              error.

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

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

              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 RFC5321). (Added in
              7.34.0)

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

              --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 will not start and curl will
              return with exit code 63.

              A size modifier may be used. For example, Appending 'k' or
              'K' will count the 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: The file size is not always known prior to download,
              and for such files this option has no effect even if the
              file transfer ends up being larger than this given limit.
              If --max-filesize is provided several times, the last set
              value will be 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 will be used.

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

              See also -L, --location.

       -m, --max-time <fractional seconds>
              Maximum time in seconds that you allow each transfer to
              take.  This is useful for preventing your batch jobs from
              hanging for hours due to slow networks or links going
              down.  Since 7.32.0, this option accepts decimal values,
              but the actual timeout will decrease in accuracy as the
              specified timeout increases in decimal precision.

              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 will be 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 has been disabled in curl since
              7.78.0 for security reasons.

              If --metalink is provided several times, the last set
              value will be 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
              support. 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.

              If this option is used several times, only the first one
              is 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 will abide by --netrc-optional if specified.

              If --netrc-file is provided several times, the last set
              value will be 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 (_netrc on Windows) file in the
              user's home directory for login name and password. This is
              typically used for FTP on Unix. If used with HTTP, curl
              will enable user authentication. See netrc(5) and ftp(1)
              for details on the file format. Curl will not complain if
              that file does not have the right permissions (it should
              be neither world- nor group-readable). The environment
              variable "HOME" is used to find the home directory.

              A quick and simple example of how to setup a .netrc to
              allow curl to FTP to the 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.
              Disable 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 will reset all local options and only global
              ones will have their values survive over to the operation
              following the -:, --next instruction. Global options
              include -v, --verbose, --trace, --trace-ascii and --fail-
              early.

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

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

              -:, --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. Added in 7.36.0.

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

              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. Added in
              7.36.0.

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

              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 will 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.
              Disable 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) In curl 7.86.0 and later, curl never uses NPN.

              Disable the NPN TLS extension. NPN is enabled by default
              if libcurl was built with an SSL library that supports
              NPN. NPN is used by a libcurl that supports HTTP/2 to
              negotiate HTTP/2 support with the server during https
              sessions.

              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. Added in
              7.36.0.

       --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 contains the hostname, or the
              hostname itself. For example, local.com would match
              local.com, local.com:80, and www.local.com, but not
              www.notlocal.com.

              Since 7.53.0, This option overrides the environment
              variables that disable the proxy ('no_proxy' and
              'NO_PROXY'). If there's an environment variable disabling
              a proxy, you can set the noproxy list to "" to override
              it.

              Since 7.86.0, IP addresses specified to this option can be
              provided using CIDR notation: an appended slash and number
              specifies 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
              will be 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 people and implemented in
              curl based on their efforts. This kind of behavior should
              not be endorsed, you should encourage everyone who uses
              NTLM to switch to a public and documented authentication
              method instead, such as Digest.

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

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

              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
              exclusive 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 conjunction with the user name which can be specified
              as part of the --url or -u, --user options.

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

              If --oauth2-bearer is provided several times, the last set
              value will be used.

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

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

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

              If --output-dir is provided several times, the last set
              value will be used.

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

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

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

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

              or use several variables like:

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

              You may use this option as many times as the number of
              URLs you have. For example, if you specify two URLs on the
              same command line, you can use it like this:

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

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

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

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

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

                curl example.com -o /dev/null

              Or for Windows use nul:

                curl example.com -o nul

              -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].com" -o "#1_#2"
               curl -o file https://example.com -o file2 https://example.net

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

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

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

              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
              simultaneously.

              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 will be 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
              will be used.

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

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

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

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

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

              See also --request-target. Added in 7.42.0.

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

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

              PEM/DER support:

              7.39.0: OpenSSL, GnuTLS and GSKit

              7.43.0: NSS and wolfSSL

              7.47.0: mbedtls

              sha256 support:

              7.44.0: OpenSSL, GnuTLS, NSS and wolfSSL

              7.47.0: mbedtls

              Other SSL backends not supported.

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

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

              See also --hostpubsha256. Added in 7.39.0.

       --post301
              (HTTP) Tells curl to respect RFC 7231/6.4.2 and not
              convert POST requests into GET requests when following a
              301 redirection. The non-RFC behavior is ubiquitous in web
              browsers, so curl does the conversion by default to
              maintain consistency. 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 redirection. 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:// prefix to specify alternative proxy protocols.
              Use socks4://, socks4a://, socks5:// or socks5h:// to
              request the specific SOCKS version to be used. No protocol
              specified will make curl default to SOCKS4.

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

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

              If --preproxy is provided several times, the last set
              value will be used.

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

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

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

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

              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_UNSUPPORTED_PROTOCOL (1).

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

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

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

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

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

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

              Example, allow only HTTP and HTTPS on redirect:

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

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

              If --proto-redir is provided several times, the last set
              value will be 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
                 permitted (this is the default if no modifier is used).

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

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

              For example:

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

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

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

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

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

              If --proto is provided several times, the last set value
              will be 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
              communicating 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 will otherwise use a CA store provided in a single
              file or directory, but when using this option it will
              interface 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.

              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 will be 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 will be 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 will be 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 will be 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.

              If --proxy-ciphers is provided several times, the last set
              value will be 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 will be 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 communication only like in CONNECT requests
              when you want a separate header sent to the proxy to what
              is sent to the actual remote host.

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

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

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

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

              --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. Added in 7.37.0.

       --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 will stick 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 will be 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 will be 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 will be 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 separated by ';'.

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

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

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

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

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

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

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

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

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

              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 will be used.

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

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

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

              If --proxy-tlsauthtype is provided several times, the last
              set value will be 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 will be 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 will be 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
              authentication.

              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 specifying a single colon with this option:
              "-U :".

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

              If -U, --proxy-user is provided several times, the last
              set value will be used.

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

              See also --proxy-pass.

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

              The proxy string can be specified with a protocol://
              prefix. No protocol specified or http:// will be treated
              as HTTP proxy. Use socks4://, socks4a://, socks5:// or
              socks5h:// to request a specific SOCKS version to be used.

              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 via https:// protocol prefix was added
              in 7.52.0 for OpenSSL, GnuTLS and NSS. Since 7.87.0, it
              also works for BearSSL, mbedTLS, rustls, Schannel, Secure
              Transport and wolfSSL.

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

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

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

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

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

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

              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 will be used.

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

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

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

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

              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 will
              make curl tunnel 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 public key in this separate file.

              (As of 7.39.0, 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
              will be 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 will stop 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 will
              be aborted.

              You must send syntactically correct FTP commands as RFC
              959 defines to FTP servers, or one of the commands listed
              below to SFTP servers.

              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 characters. Following is the list of all
              supported SFTP quote commands:

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

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

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

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

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

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

              pwd    The pwd command returns the absolute pathname of
                     the current working 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 operand.

              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 by curl since
              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 what will be
              considered as 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 will be 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
              document) from an HTTP/1.1, FTP or SFTP server or a local
              FILE. Ranges can be specified in a number of ways.

              0-499  specifies the first 500 bytes

              500-999
                     specifies the second 500 bytes

              -500   specifies the last 500 bytes

              9500-  specifies the bytes from offset 9500 and forward

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

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

              (*) = NOTE that this will cause the server to reply with a
              multipart response, which will be returned as-is by curl!
              Parsing or otherwise transforming this 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 character is given in the range, the server's
              response will be unspecified, depending on the server's
              configuration.

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

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

              If -r, --range is provided several times, the last set
              value will be 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
              will start the next transfer as fast as possible.

              If given several URLs and a transfer completes faster than
              the allowed rate, curl will wait 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 number 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 transfers per hour.

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

              This function uses millisecond resolution. If the allowed
              frequency is set more than 1000 per second, it will
              instead run unrestricted.

              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
              will be 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 content 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 will be used.

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

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

       -J, --remote-header-name
              (HTTP) This option tells the -O, --remote-name option to
              use the server-specified Content-Disposition filename
              instead of extracting a filename from the URL. If the
              server-provided file name contains a path, that will be
              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 will
              not be overwritten and an error will occur - 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's 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 will be saved in the current working directory.
              If you want the file saved in a different directory, make
              sure you change the current working directory before
              invoking curl with this option 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
              will be overwritten. If you want the server to be able to
              choose the file name refer to -J, --remote-header-name
              which can be used in addition to this option. If the
              server chooses a file name and that name already exists it
              will not be overwritten.

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

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

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

              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 will be used.

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

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

       -X, --request <method>
              (HTTP) Specifies a custom request method to use when
              communicating with the HTTP server. The specified request
              method will be used instead of the method otherwise used
              (which defaults to GET). Read the HTTP 1.1 specification
              for details and explanations. 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 will not suffice. You need to use the -I, --head
              option.

              The method string you set with -X, --request will be used
              for all requests, which if you for example use -L,
              --location may cause unintended side-effects when curl
              does not change request method according to the HTTP 30x
              response codes - and 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. (Added in 7.30.0)

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

              If -X, --request is provided several times, the last set
              value will be used.

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

              See also --request-target.

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

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

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

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

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

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

              Support for resolving with wildcard was added in 7.64.0.

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

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

              --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 (eg in curlrc), there may be
              unintended consequences such as sending or receiving
              duplicate data. Do not use with redirected input or
              output. You'd be much better off handling your unique
              problems in shell script. Please read the example below.

              WARNING: For server compatibility curl attempts to retry
              failed flaky transfers as close as possible to how they
              were started, but this is not possible with 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 will not error on 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 will retry 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 combine 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 will make curl use the default
              backoff time.

              If --retry-delay is provided several times, the last set
              value will be 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 will be done as usual (see --retry) as
              long as the timer has not reached this given limit. Notice
              that if the timer has not reached the limit, the request
              will be made and while performing, it may take longer than
              this given time period. To limit a single 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 will be used.

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

              See also --retry.

       --retry <num>
              If a transient error is returned when curl tries to
              perform a transfer, it will retry this number of times
              before giving up. Setting the number to 0 makes curl do no
              retries (which is the default). Transient error means
              either: a timeout, an FTP 4xx response code or an HTTP
              408, 429, 500, 502, 503 or 504 response code.

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

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

              If --retry is provided several times, the last set value
              will be 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 will derive 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 will be 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. Added in 7.31.0.

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

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

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

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

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

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

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

              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
              messages. Makes Curl mute. It will still output the data
              you ask for, potentially even to the terminal/stdout
              unless you redirect it.

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

              Providing -s, --silent multiple times has no extra effect.
              Disable 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
              specified, it is assumed at port 1080. Using this socket
              type make curl resolve the host name and passing the
              address on to the proxy.

              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.

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

              If --socks4 is provided several times, the last set value
              will be used.

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

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

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

              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.

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

              If --socks4a is provided several times, the last set value
              will be used.

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

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

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

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

              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.

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

              If --socks5-gssapi-service is provided several times, the
              last set value will be 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
              hostname proxy with -x, --proxy using a socks5h://
              protocol prefix.

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

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

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

              See also --socks5 and --socks4a.

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

              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.

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

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

              If --socks5 is provided several times, the last set value
              will be 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 second) 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 will be used.

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

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

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

              This option controls transfers (in both directions) but
              will 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 will be used.

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

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

       --ssl-allow-beast
              This option tells curl to not work around a security flaw
              in the SSL3 and TLS1.0 protocols known as BEAST.  If this
              option is not used, the SSL layer may use workarounds
              known to cause interoperability problems with some older
              SSL implementations.

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

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

              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
              revocation 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. Added in 7.44.0.

       --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 since version 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 transfers will
              always fail 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.
              Disable 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
              revocation 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
              insecure 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 encryption required.

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

              Please note that a server may close the connection if the
              negotiation does not succeed.

              This option was formerly known as --ftp-ssl. That option
              name can still be used but will 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
              starting in curl 7.77.0 this instruction is ignored. 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
              starting in curl 7.77.0 this instruction is ignored. 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
              will be used.

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

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

       --styled-output
              Enables the automatic use of bold font styles when writing
              HTTP headers to the 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 statistics.

              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 (RFC7413).

              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. Added in 7.49.0.

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

              Since 7.50.2, curl sets this option by default and you
              need to explicitly switch it off if you do not want it on.

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

              If --tftp-blksize is provided several times, the last set
              value will be used.

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

              See also --tftp-no-options.

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

              This option improves interop with some legacy servers that
              do not acknowledge or properly implement TFTP options.
              When this option is used --tftp-blksize is 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. Added in 7.48.0.

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

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

              If -z, --time-cond is provided several times, the last set
              value will be used.

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

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

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

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

              default
                     Use up to recommended TLS version.

              1.0    Use up to TLSv1.0.

              1.1    Use up to TLSv1.1.

              1.2    Use up to TLSv1.2.

              1.3    Use up to TLSv1.3.

              If --tls-max is provided several times, the last set value
              will be 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 support TLS. Added in 7.54.0.

       --tls13-ciphers <ciphersuite list>
              (TLS) Specifies which cipher suites to use in the
              connection if it negotiates TLS 1.3. The list of ciphers
              suites must specify valid ciphers. Read up on TLS 1.3
              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
              different 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 will be used.

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

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

       --tlsauthtype <type>
              Set TLS authentication type. Currently, the only supported
              option is "SRP", for TLS-SRP (RFC 5054). If --tlsuser and
              --tlspassword are specified but --tlsauthtype is not, then
              this option defaults to "SRP". This option works only if
              the underlying 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 will be used.

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

              See also --tlsuser.

       --tlspassword <string>
              Set password for use with the TLS authentication method
              specified 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 will be used.

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

              See also --tlsuser.

       --tlsuser <name>
              Set username for use with the TLS authentication method
              specified with --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
              will be 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
              connecting to a remote TLS server.

              In old versions of curl this option was documented to
              allow _only_ TLS 1.0.  That behavior was inconsistent
              depending on the TLS library. Use --tls-max if you want to
              set a maximum TLS version.

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

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

              See also --tlsv1.3. Added in 7.34.0.

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

              In old versions of curl this option was documented to
              allow _only_ TLS 1.1.  That behavior was inconsistent
              depending on the TLS library. Use --tls-max if you want to
              set a maximum TLS version.

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

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

              See also --tlsv1.3 and --tls-max. Added in 7.34.0.

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

              In old versions of curl this option was documented to
              allow _only_ TLS 1.2.  That behavior was inconsistent
              depending on the TLS library. Use --tls-max if you want to
              set a maximum TLS version.

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

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

              See also --tlsv1.3 and --tls-max. Added in 7.34.0.

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

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

              Note that TLS 1.3 is not supported by all TLS backends.

              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
              (SSL) Tells curl to use at least TLS version 1.x when
              negotiating with a remote TLS server. That means TLS
              version 1.0 or higher

              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.

              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 will be 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-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.
              Disable 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.
              Disable 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.

              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
              will be used.

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

              See also --trace-ascii, --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 will be used.

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

              See also --abstract-unix-socket. Added in 7.40.0.

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

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

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

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

              -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 and -I, --head.

       --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 will make a guess
              based on the host. If the outermost sub-domain name
              matches DICT, FTP, IMAP, LDAP, POP3 or SMTP then that
              protocol will be used, otherwise HTTP will be used. Since
              7.45.0 guessing can be disabled by setting a default
              protocol, see --proto-default for details.

              To control where this URL is written, use the -o, --output
              or the -O, --remote-name options.

              WARNING: On Windows, particular file:// accesses can be
              converted to network 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
              will remove 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 will be used.

              Example:
               curl -A "Agent 007" https://example.com

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

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

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

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

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

              When using Kerberos V5 with a Windows based server you
              should include the Windows domain name in the user name,
              in order for the server to successfully obtain a 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
              Kerberos V5, Negotiate, NTLM or Digest authentication then
              you can tell curl to select the user name and password
              from your environment by specifying a single colon with
              this option: "-u :".

              If -u, --user is provided several times, the last set
              value will be used.

              Example:
               curl -u user:secret https://example.com

              See also -n, --netrc and -K, --config.

       -v, --verbose
              Makes curl verbose during the operation. Useful for
              debugging and seeing what's 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.

              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 "Protocols:") shows all
              protocols that libcurl reports to support.

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

              alt-svc
                     Support for the Alt-Svc: header is provided.

              AsynchDNS
                     This curl uses asynchronous name resolves.
                     Asynchronous name resolves can be done using either
                     the c-ares or the threaded resolver backends.

              brotli Support for automatic brotli compression over
                     HTTP(S).

              CharConv
                     curl was built with support for character set
                     conversions (like EBCDIC)

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

              gsasl  The built-in SASL authentication includes
                     extensions to support SCRAM 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 suffixes".

              SPNEGO SPNEGO authentication is supported.

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

              SSPI   SSPI is supported.

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

              TrackMemory
                     Debug memory tracking is supported.

              Unicode
                     Unicode support on Windows.

              UnixSockets
                     Unix sockets support is provided.

              zstd   Automatic decompression (via zstd) of compressed
                     files over HTTP is supported.

              Example:
               curl --version

              See also -h, --help and -M, --manual.

       -w, --write-out <format>
              Make curl display information on stdout after a completed
              transfer. The format is a string that may contain plain
              text mixed with any number of variables. The format can be
              specified as a literal "string", or you can have curl read
              the format from a file with "@filename" and to tell curl
              to read the format from stdin you write "@-".

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

              The output will be written to standard output, but this
              can be switched to standard error by using %{stderr}.

              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 curl
              7.84.0.

              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.
                     Supported only by the OpenSSL, GnuTLS, Schannel,
                     NSS, GSKit 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 exitcode 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 presented
                     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, NSS, GSKit and Secure Transport backends.
                     (Added in 7.88.0)

              num_connects
                     Number of new connects made in the recent transfer.

              num_headers
                     The number of response headers in the most recent
                     request (restarted at each redirect). Note that the
                     status line IS NOT a header. (Added in 7.73.0)

              num_redirects
                     Number of redirects that were followed in the
                     request.

              onerror
                     The rest of the output is only shown if the
                     transfer returned a non-zero error.  (Added in
                     7.75.0)

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

              redirect_url
                     When an HTTP request was made without -L,
                     --location to follow redirects (or when --max-
                     redirs is met), this variable will show the actual
                     URL a redirect would have gone to.

              referer
                     The Referer: header, if there was any. (Added in
                     7.76.0)

              remote_ip
                     The remote IP address of the most recently done
                     connection - can be either IPv4 or IPv6.

              remote_port
                     The remote port number of the most recently done
                     connection.

              response_code
                     The numerical response code that was found in the
                     last transfer (formerly known as "http_code").

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

              size_download
                     The total amount of bytes that were downloaded.
                     This is the size of the body/data that was
                     transferred, excluding headers.

              size_header
                     The total amount of bytes of the downloaded
                     headers.

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

              size_upload
                     The total amount of bytes that were uploaded. This
                     is the size of the body/data that was transferred,
                     excluding headers.

              speed_download
                     The average download speed that curl measured for
                     the complete 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 verification
                     that was requested. 0 means the verification was
                     successful.

              stderr From this point on, the -w, --write-out output will
                     be written to standard error. (Added in 7.63.0)

              stdout From this point on, the -w, --write-out output will
                     be written to standard output.  This is the
                     default, but can be used to switch back after
                     switching to stderr.  (Added in 7.63.0)

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

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

              time_namelookup
                     The time, in seconds, it took from the start until
                     the name 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 negotiations
                     that are specific to the particular protocol(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 execution
                     time for multiple redirections.

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

              time_total
                     The total time, in seconds, that the full operation
                     lasted.

              url    The URL that was fetched. (Added in 7.75.0)

              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 zoneid 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 zoneid part of the effective (last) URL that
                     was fetched. (Added in 8.1.0)

              urlnum The URL index number of this transfer, 0-indexed.
                     De-globbed URLs share the same index number as the
                     origin globbed URL. (Added in 7.75.0)

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

              If -w, --write-out is provided several times, the last set
              value will be 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         top

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

ENVIRONMENT         top

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

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

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

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

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

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

       NO_PROXY <comma-separated list of hosts/domains>
              list of host names that should not go through any proxy.
              If set to an asterisk '*' only, it matches all hosts. Each
              name in this list is matched as either a domain name which
              contains the hostname, or the hostname itself.

              This environment variable disables use of the proxy even
              when specified with the -x, --proxy option. That is
              NO_PROXY=direct.example.com curl -x
              http://proxy.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.

              Since 7.86.0, 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. 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 will be used as
              the terminal width when the alternative progress-bar is
              shown. If not set, curl will try to figure it out using
              other ways.

       CURL_CA_BUNDLE <file>
              If set, will be used as the --cacert value.

       CURL_HOME <dir>
              If set, is the first variable curl checks when trying to
              find its home directory. If not set, it continues to check
              XDG_CONFIG_HOME

       CURL_SSL_BACKEND <TLS backend>
              If curl was built with support for "MultiSSL", meaning
              that it has built-in support for more than one TLS
              backend, this environment variable can be set to the case
              insensitive name of the particular backend to use when
              curl is invoked. Setting a name that is not a built-in
              alternative will make curl stay with the default.

              SSL backend names (case-insensitive): bearssl, gnutls,
              gskit, mbedtls, nss, openssl, rustls, schannel, secure-
              transport, wolfssl

       HOME <dir>
              If set, this is used to find the home directory when that
              is needed. Like when looking for the default .curlrc.
              CURL_HOME and XDG_CONFIG_HOME have preference.

       QLOGDIR <directory name>
              If curl was built with HTTP/3 support, setting this
              environment variable to a local directory will make curl
              produce qlogs in that directory, using file names named
              after the destination connection id (in hex). Do note that
              these files can become rather large. Works with both QUIC
              backends.

       SHELL  Used on VMS when trying to detect if using a DCL or a
              "unix" shell.

       SSL_CERT_DIR <dir>
              If set, will be used as the --capath value.

       SSL_CERT_FILE <path>
              If set, will be used as the --cacert value.

       SSLKEYLOGFILE <file name>
              If you set this environment variable to a file name, curl
              will store TLS secrets from its connections in that file
              when invoked to enable you to analyze the TLS traffic in
              real time using network analyzing tools such as Wireshark.
              This works with the following TLS backends: OpenSSL,
              libressl, BoringSSL, GnuTLS, NSS and wolfSSL.

       USERPROFILE <dir>
              On Windows, this variable is used when trying to find the
              home directory. If the other, primary, variable are all
              unset. If set, curl will use the path
              "$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         top

       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 will be treated as an
       HTTP proxy.

       The supported proxy protocol prefixes are as follows:

       http://
              Makes it use it as an HTTP proxy. The default if no scheme
              prefix is used.

       https://
              Makes it treated as an HTTPS proxy.

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

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

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

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

EXIT CODES         top

       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
              similar) command failed.

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

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

       23     Write error. Curl could not write data to a local
              filesystem or similar.

       25     FTP could not STOR file. The server denied the STOR
              operation, used for FTP 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
              download.

       37     FILE could not read file. Failed to open the file.
              Permissions?

       38     LDAP cannot bind. LDAP bind operation failed.

       39     LDAP search failed.

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

       42     Aborted by callback. An application told curl to abort the
              operation.

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

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

       47     Too many redirects. When following redirects, curl hit the
              maximum amount.

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

       49     Malformed telnet option.

       52     The server did not reply anything, which here is
              considered an error.

       53     SSL crypto engine not found.

       54     Cannot set SSL crypto engine as default.

       55     Failed sending network data.

       56     Failure in receiving network data.

       58     Problem with the local certificate.

       59     Could not use specified SSL cipher.

       60     Peer certificate cannot be authenticated with known CA
              certificates.

       61     Unrecognized transfer encoding.

       63     Maximum file size exceeded.

       64     Requested FTP SSL level failed.

       65     Sending the data requires a rewind that failed.

       66     Failed to initialise SSL Engine.

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

       68     File not found on TFTP server.

       69     Permission problem on TFTP server.

       70     Out of disk space on TFTP server.

       71     Illegal TFTP operation.

       72     Unknown TFTP transfer ID.

       73     File already exists (TFTP).

       74     No such user (TFTP).

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

       78     The resource referenced in the URL does not exist.

       79     An unspecified error occurred during the SSH session.

       80     Failed to shut down the SSL connection.

       82     Could not load CRL file, missing or wrong format.

       83     Issuer check failed.

       84     The FTP PRET command failed.

       85     Mismatch of RTSP CSeq numbers.

       86     Mismatch of RTSP Session Identifiers.

       87     Unable to parse FTP file list.

       88     FTP chunk callback reported error.

       89     No connection available, the session will be queued.

       90     SSL public key does not matched pinned public key.

       91     Invalid SSL certificate status.

       92     Stream error in HTTP/2 framing layer.

       93     An API function was called from inside a callback.

       94     An authentication function returned an error.

       95     A problem was detected in the HTTP/3 layer. This is
              somewhat generic and can be one out of several problems,
              see the error message for details.

       96     QUIC connection error. This error may be caused by an SSL
              library error. QUIC is the protocol used for HTTP/3
              transfers.

       97     Proxy handshake error.

       98     A client-side certificate is required to complete the TLS
              handshake.

       99     Poll or select returned fatal error.

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

BUGS         top

       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         top

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

WWW         top

       https://curl.se

SEE ALSO         top

       ftp(1), wget(1)

COLOPHON         top

       This page is part of the curl (Command line tool and library for
       transferring data with URLs) project.  Information about the
       project can be found at ⟨https://curl.haxx.se/⟩.  If you have a
       bug report for this manual page, see
       ⟨https://curl.haxx.se/docs/bugs.html⟩.  This page was obtained
       from the project's upstream Git repository
       ⟨https://github.com/curl/curl.git⟩ on 2023-06-23.  (At that time,
       the date of the most recent commit that was found in the
       repository was 2023-06-23.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

curl 8.2.0                    June 23 2023                       curl(1)

Pages that refer to this page: curl-config(1)git-config(1)mk-ca-bundle(1)pmwebapi(3)systemd-socket-proxyd(8)update-pciids(8)