curl.1

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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.

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.

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 autentication, 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 autentication, 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.

If this option is used twice, the second will again disable verbose.
.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 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"
This curl uses asynchronous name resolves.
.IP "SPNEGO"
SPNEGO Negotiate authentication is supported.
.IP "Largefile"
This curl supports transfers of large files, files larger than 2GB.
.IP "IDN"
This curl supports IDN - international domain names.
.IP "SSPI"
SSPI is supported. If you use NTLM and set a blank user name, curl will
authenticate with your current user and password.
.RE
.IP "-w/--write-out <format>"
Defines what to display on stdout after a completed and successful
operation. The format is a string that may contain plain text mixed with any
number of variables. The string can be specified as "string", to get read from
a particular file you specify it "@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
like %{variable_name} and to output a normal % you just write them like
%%. You can output a newline by using \\n, a carriage return with \\r and a tab
space with \\t.

.B NOTE:
The %-letter is a special letter in the win32-environment, where all
occurrences of % must be doubled when using this option.

Available variables are at this point:
.RS
.TP 15
.B url_effective
The URL that was fetched last. This is mostly meaningful if you've told curl
to follow location: headers.
.TP
.B http_code
The numerical code that was found in the last retrieved HTTP(S) page.
.TP
.B http_connect
The numerical code that was found in the last response (from a proxy) to a
curl CONNECT request. (Added in 7.12.4)
.TP
.B time_total
The total time, in seconds, that the full operation lasted. The time will be
displayed with millisecond resolution.
.TP
.B time_namelookup
The time, in seconds, it took from the start until the name resolving was
completed.
.TP
.B time_connect
The time, in seconds, it took from the start until the connect to the remote
host (or proxy) was completed.
.TP
.B time_pretransfer
The time, in seconds, it took from the start until the file transfer is just
about to begin. This includes all pre-transfer commands and negotiations that
are specific to the particular protocol(s) involved.
.TP
.B time_redirect
The time, in seconds, it took for all redirection steps include name lookup,
connect, pretransfer and transfer before final transaction was
started. time_redirect shows the complete execution time for multiple
redirections. (Added in 7.12.3)
.TP
.B time_starttransfer
The time, in seconds, it took from the start until the first byte is just about
to be transferred. This includes time_pretransfer and also the time the
server needs to calculate the result.
.TP
.B size_download
The total amount of bytes that were downloaded.
.TP
.B size_upload
The total amount of bytes that were uploaded.
.TP
.B size_header
The total amount of bytes of the downloaded headers.
.TP
.B size_request
The total amount of bytes that were sent in the HTTP request.
.TP
.B speed_download
The average download speed that curl measured for the complete download.
.TP
.B speed_upload
The average upload speed that curl measured for the complete upload.
.TP
.B content_type
The Content-Type of the requested document, if there was any.
.TP
.B num_connects
Number of new connects made in the recent transfer. (Added in 7.12.3)
.TP
.B num_redirects
Number of redirects that were followed in the request. (Added in 7.12.3)
.TP
.B ftp_entry_path
The initial path libcurl ended up in when logging on to the remote FTP
server. (Added in 7.15.4)
.RE

If this option is used several times, the last one will be used.
.IP "-x/--proxy <proxyhost[:port]>"
Use specified HTTP proxy. If the port number is not specified, it is assumed
at port 1080.

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