curl.1

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protocols to attempt to tunnel through the proxy instead of merely using it to
do HTTP-like operations. The tunnel approach is made with the HTTP proxy
CONNECT request and requires that the proxy allows direct connect to the
remote port number curl wants to tunnel through to.

If this option is used twice, the second will again disable proxy tunnel.
.IP "--pubkey <key>"
(SSH) Public key file name. Allows you to provide your public key in this
separate file.

If this option is used several times, the last one will be used.
.IP "-P/--ftp-port <address>"
(FTP) Reverses the initiator/listener roles when connecting with ftp. This
switch makes Curl use the PORT command instead of PASV. In practise, PORT
tells the server to connect to the client's specified address and port, while
PASV asks the server for an ip address and port to connect to. <address>
should be one of:
.RS
.IP interface
i.e "eth0" to specify which interface's IP address you want to use  (Unix only)
.IP "IP address"
i.e "192.168.10.1" to specify exact IP number
.IP "host name"
i.e "my.host.domain" to specify machine
.IP "-"
make curl pick the same IP address that is already used for the control
connection
.RE

If this option is used several times, the last one will be used. Disable the
use of PORT with \fI--ftp-pasv\fP. Disable the attempt to use the EPRT command
instead of PORT by using \fI--disable-eprt\fP. EPRT is really PORT++.
.IP "-q"
If used as the first parameter on the command line, the \fIcurlrc\fP config
file will not be read and used. See the \fI-K/--config\fP for details on the
default config file search path.
.IP "-Q/--quote <command>"
(FTP/SFTP) Send an arbitrary command to the remote FTP or SFTP server. Quote
commands are sent BEFORE the transfer is taking place (just after the
initial PWD command in an FTP transfer, to be exact). To make commands
take place after a successful transfer, prefix them with a dash '-'.
To make commands get sent after libcurl has changed working directory,
just before the transfer command(s), prefix the command with '+' (this
is only supported for FTP). You may specify any number of commands. If
the server returns failure for one of the commands, the entire operation
will be aborted. You must send syntactically correct FTP commands as
RFC959 defines to FTP servers, or one of the following commands (with
appropriate arguments) to SFTP servers: chgrp, chmod, chown, ln, mkdir,
pwd, rename, rm, rmdir, symlink.

This option can be used multiple times.
.IP "--random-file <file>"
(SSL) Specify the path name to file containing what will be considered as
random data. The data is used to seed the random engine for SSL connections.
See also the \fI--egd-file\fP option.
.IP "-r/--range <range>"
(HTTP/FTP)
Retrieve a byte range (i.e a partial document) from a HTTP/1.1 or FTP
server. Ranges can be specified in a number of ways.
.RS
.TP 10
.B 0-499
specifies the first 500 bytes
.TP
.B 500-999
specifies the second 500 bytes
.TP
.B -500
specifies the last 500 bytes
.TP
.B 9500-
specifies the bytes from offset 9500 and forward
.TP
.B 0-0,-1
specifies the first and last byte only(*)(H)
.TP
.B 500-700,600-799
specifies 300 bytes from offset 500(H)
.TP
.B 100-199,500-599
specifies two separate 100 bytes ranges(*)(H)
.RE

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

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

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

FTP range downloads only support the simple syntax 'start-stop' (optionally
with one of the numbers omitted). It depends on the non-RFC command SIZE.

If this option is used several times, the last one will be used.
.IP "--raw"
When used, it disables all internal HTTP decoding of content or transfer
encodings and instead makes them passed on unaltered, raw. (Added in 7.16.2)

If this option is used several times, each occurrence toggles this on/off.
.IP "-R/--remote-time"
When used, this will make libcurl attempt to figure out the timestamp of the
remote file, and if that is available make the local file get that same
timestamp.

If this option is used twice, the second time disables this again.
.IP "--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 5xx response code or an HTTP 5xx response code.

When curl is about to retry a transfer, it will first wait one second and then
for all forthcoming retries it will double the waiting time until it reaches
10 minutes which then will be the delay between the rest of the retries.  By
using \fI--retry-delay\fP you disable this exponential backoff algorithm. See
also \fI--retry-max-time\fP to limit the total time allowed for
retries. (Added in 7.12.3)

If this option is used multiple times, the last occurrence decide the amount.
.IP "--retry-delay <seconds>"
Make curl sleep this amount of time between 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 \fI--retry\fP is also
used. Setting this delay to zero will make curl use the default backoff time.
(Added in 7.12.3)

If this option is used multiple times, the last occurrence decide the amount.
.IP "--retry-max-time <seconds>"
The retry timer is reset before the first transfer attempt. Retries will be
done as usual (see \fI--retry\fP) as long as the timer hasn't reached this
given limit. Notice that if the timer hasn't reached the limit, the request
will be made and while performing, it may take longer than this given time
period. To limit a single request\'s maximum time, use \fI-m/--max-time\fP.
Set this option to zero to not timeout retries. (Added in 7.12.3)

If this option is used multiple times, the last occurrence decide the amount.
.IP "-s/--silent"
Silent mode. Don't show progress meter or error messages.  Makes
Curl mute.

If this option is used twice, the second will again disable silent mode.
.IP "-S/--show-error"
When used with -s it makes curl show error message if it fails.

If this option is used twice, the second will again disable show error.
.IP "--socks4 <host[:port]>"
Use the specified SOCKS4 proxy. If the port number is not specified, it is
assumed at port 1080. (Added in 7.15.2)

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

If this option is used several times, the last one will be used.
.IP "--socks5 <host[:port]>"
Use the specified SOCKS5 proxy. If the port number is not specified, it is
assumed at port 1080. (Added in 7.11.1)

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

If this option is used several times, the last one will be used. (This option
was previously wrongly documented and used as --socks without the number
appended.)
.IP "--stderr <file>"
Redirect all writes to stderr to the specified file instead. If the file name
is a plain '-', it is instead written to stdout. This option has no point when
you're using a shell with decent redirecting capabilities.

If this option is used several times, the last one will be used.
.IP "--tcp-nodelay"
Turn on the TCP_NODELAY option. See the \fIcurl_easy_setopt(3)\fP man page for
details about this option. (Added in 7.11.2)

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

Use the file name "-" (a single dash) to use stdin instead of a given file.

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

curl -T "{file1,file2}" http://www.uploadtothissite.com

or even

curl -T "img[1-1000].png" ftp://ftp.picturemania.com/upload/
.IP "--trace <file>"
Enables a full trace dump of all incoming and outgoing data, including
descriptive information, to the given output file. Use "-" as filename to have
the output sent to stdout.

This option overrides previous uses of \fI-v/--verbose\fP or
\fI--trace-ascii\fP.

If this option is used several times, the last one will be used.
.IP "--trace-ascii <file>"
Enables a full trace dump of all incoming and outgoing data, including
descriptive information, to the given output file. Use "-" as filename to have
the output sent to stdout.

This is very similar to \fI--trace\fP, but leaves out the hex part and only
shows the ASCII part of the dump. It makes smaller output that might be easier
to read for untrained humans.

This option overrides previous uses of \fI-v/--verbose\fP or \fI--trace\fP.

If this option is used several times, the last one will be used.
.IP "--trace-time"
Prepends a time stamp to each trace or verbose line that curl displays.
(Added in 7.14.0)

If this option is used several times, each occurrence will toggle it on/off.
.IP "-u/--user <user:password>"
Specify user and password to use for server authentication. Overrides
\fI-n/--netrc\fP and \fI--netrc-optional\fP.

If you use an SSPI-enabled curl binary and do NTLM authentication, you can
force curl to pick up the user name and password from your environment by
simply specifying a single colon with this option: "-u :".

If this option is used several times, the last one will be used.
.IP "-U/--proxy-user <user:password>"
Specify user and password to use for proxy authentication.

If you use an SSPI-enabled curl binary and do NTLM authentication, you can
force curl to pick up the user name and password from your environment by
simply specifying a single colon with this option: "-U :".

If this option is used several times, the last one will be used.
.IP "--url <URL>"
Specify a URL to fetch. This option is mostly handy when you want to specify
URL(s) in a config file.

This option may be used any number of times. To control where this URL is
written, use the \fI-o/--output\fP or the \fI-O/--remote-name\fP options.
.IP "-v/--verbose"
Makes the fetching more verbose/talkative. Mostly usable for debugging. Lines
starting with '>' means "header data" sent by curl, '<' means "header data"
received by curl that is hidden in normal cases and lines starting with '*'
means additional info provided by curl.

Note that if you only want HTTP headers in the output, \fI-i/--include\fP
might be option you're looking for.

If you think this option still doesn't give you enough details, consider using
\fI--trace\fP or \fI--trace-ascii\fP instead.

This option overrides previous uses of \fI--trace-ascii\fP or \fI--trace\fP.

If this option is used twice, the second will do nothing extra.
.IP "-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:
.RS
.IP "IPv6"
You can use IPv6 with this.
.IP "krb4"
Krb4 for ftp is supported.
.IP "SSL"
HTTPS and FTPS are supported.
.IP "libz"
Automatic decompression of compressed files over HTTP is supported.
.IP "NTLM"
NTLM authentication is supported.
.IP "GSS-Negotiate"
Negotiate authentication and krb5 for ftp is supported.
.IP "Debug"
This curl uses a libcurl built with Debug. This enables more error-tracking
and memory debugging etc. For curl-developers only!
.IP "AsynchDNS"