hello world

[icculus/iodoom3.git] / neo / curl / docs / curl.1

.\" You can view this file with:
.\" nroff -man curl.1
.\" Written by Daniel Stenberg
.\"
.TH curl 1 "5 Mar 2004" "Curl 7.11.1" "Curl Manual"
.SH NAME
curl \- transfer a URL
.SH SYNOPSIS
.B curl [options]
.I [URL...]
.SH DESCRIPTION
.B curl
is a tool to transfer data from or to a server, using one of the supported
protocols (HTTP, HTTPS, FTP, FTPS, GOPHER, DICT, TELNET, LDAP or FILE). 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 (https:) connections, cookies, file
transfer resume and more. As you will see below, the amount of features will
make your head spin!

curl is powered by libcurl for all transfer-related features. See
.BR libcurl (3)
for details.
.SH URL
The URL syntax is protocol dependent. You'll find a detailed description in
RFC 2396.

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

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

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

 ftp://ftp.numericals.com/file[1-100].txt
 ftp://ftp.numericals.com/file[001-100].txt    (with leading zeros)
 ftp://ftp.letters.com/file[a-z].txt

No nesting of the sequences is supported at the moment:

 http://www.any.org/archive[1996-1999]/volume[1-4]part{a,b,c,index}.html

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

Curl will attempt to re-use connections for multiple file transfers, so that
getting many files from the same server will not do multiple connects /
handshakes. This improves speed. Of course this is only done on files
specified on a single command line and cannot be used between separate curl
invokes.
.SH OPTIONS
.IP "-a/--append"
(FTP) When used in an FTP upload, this will tell curl to append to the target
file instead of overwriting it. If the file doesn't exist, it will be created.

If this option is used twice, the second one will disable append mode again.
.IP "-A/--user-agent <agent string>"
(HTTP) Specify the User-Agent string to send to the HTTP server. Some badly
done CGIs fail if its not set to "Mozilla/4.0".  To encode blanks in the
string, surround the string with single quote marks.  This can also be set
with the \fI-H/--header\fP option of course.

If this option is set more than once, the last one will be the one that's
used.
.IP "--anyauth"
(HTTP) Tells curl to figure out authentication method by itself, and use the
most secure one the remote site claims it supports. This is done by first
doing a request and checking the response-headers, thus inducing an extra
network round-trip. This is used instead of setting a specific authentication
method, which you can do with \fI--basic\fP, \fI--digest\fP, \fI--ntlm\fP, and
\fI--negotiate\fP. (Added in 7.10.6)

If this option is used several times, the following occurrences make no
difference.
.IP "-b/--cookie <name=data>"
(HTTP)
Pass the data to the HTTP server as a cookie. It is supposedly the
data previously received from the server in a "Set-Cookie:" line.
The data should be in the format "NAME1=VALUE1; NAME2=VALUE2".

If no '=' letter is used in the line, it is treated as a filename to use to
read previously stored cookie lines from, which should be used in this session
if they match. Using this method also activates the "cookie parser" which will
make curl record incoming cookies too, which may be handy if you're using this
in combination with the \fI-L/--location\fP option. The file format of the
file to read cookies from should be plain HTTP headers or the Netscape/Mozilla
cookie file format.

\fBNOTE\fP that the file specified with \fI-b/--cookie\fP is only used as
input. No cookies will be stored in the file. To store cookies, use the
\fI-c/--cookie-jar\fP option or you could even save the HTTP headers to a file
using \fI-D/--dump-header\fP!

If this option is set more than once, the last one will be the one that's
used.
.IP "-B/--use-ascii"
Use ASCII transfer when getting an FTP file or LDAP info. For FTP, this can
also be enforced by using an URL that ends with ";type=A". This option causes
data sent to stdout to be in text mode for win32 systems.

If this option is used twice, the second one will disable ASCII usage.
.IP "--basic"
(HTTP) Tells curl to use HTTP Basic authentication. 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 \fI--ntlm\fP,
\fI--digest\fP and \fI--negotiate\fP). (Added in 7.10.6)

If this option is used several times, the following occurrences make no
difference.
.IP "--ciphers <list of ciphers>"
(SSL) Specifies which ciphers to use in the connection. The list of ciphers
must be using valid ciphers. Read up on SSL cipher list details on this URL:
\fIhttp://www.openssl.org/docs/apps/ciphers.html\fP

If this option is used several times, the last one will override the others.
.IP "--compressed"
(HTTP) Request a compressed response using one of the algorithms libcurl
supports, and return the uncompressed document.  If this option is used and
the server sends an unsupported encoding, Curl will report an error.

If this option is used several times, each occurrence will toggle it on/off.
.IP "--connect-timeout <seconds>"
Maximum time in seconds that you allow the connection to the server to take.
This only limits the connection phase, once curl has connected this option is
of no more use. See also the \fI--max-time\fP option.

If this option is used several times, the last one will be used.
.IP "-c/--cookie-jar <file name>"
Specify to which file you want curl to write all cookies after a completed
operation. Curl writes all cookies previously read from a specified file as
well as all cookies received from remote server(s). If no cookies are known,
no file 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.

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

If this option is used several times, the last specfied file name will be
used.
.IP "-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 counted from the beginning
of the source file before it is transfered to the destination.  If used with
uploads, the ftp server command SIZE will not be used by curl.

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

If this option is used several times, the last one will be used.
.IP "--create-dirs"
When used in conjunction with the -o option, curl will create the necessary 
local directory hierarchy as needed.
.IP "--crlf"
(FTP) Convert LF to CRLF in upload. Useful for MVS (OS/390).

If this option is used twice, the second will again disable crlf converting.
.IP "-d/--data <data>"
(HTTP) Sends the specified data in a POST request to the HTTP server, in a way
that can emulate as if a user has filled in a HTML form and pressed the submit
button. Note that the data is sent exactly as specified with no extra
processing (with all newlines cut off).  The data is expected to be
\&"url-encoded". This will cause curl to pass the data to the server using the
content-type application/x-www-form-urlencoded. Compare to \fI-F/--form\fP. If
this option is used more than once on the same command line, the data pieces
specified will be merged together with a separating &-letter. 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.  The
contents of the file must already be url-encoded. Multiple files can also be
specified. Posting data from a file named 'foobar' would thus be done with
\fI--data\fP @foobar".

To post data purely binary, you should instead use the \fI--data-binary\fP
option.

\fI-d/--data\fP is the same as \fI--data-ascii\fP.

If this option is used several times, the ones following the first will
append data.
.IP "--data-ascii <data>"
(HTTP) This is an alias for the \fI-d/--data\fP option.

If this option is used several times, the ones following the first will
append data.
.IP "--data-binary <data>"
(HTTP) This posts data in a similar manner as \fI--data-ascii\fP does,
although when using this option the entire context of the posted data is kept
as-is. If you want to post a binary file without the strip-newlines feature of
the \fI--data-ascii\fP option, this is for you.

If this option is used several times, the ones following the first will
append data.
.IP "--digest"
(HTTP) Enables HTTP Digest authentication. This is a authentication that
prevents the password from being sent over the wire in clear text. Use this in
combination with the normal \fI-u/--user\fP option to set user name and
password. See also \fI--ntlm\fP, \fI--negotiate\fP and \fI--anyauth\fP for
related options. (Added in curl 7.10.6)

If this option is used several times, the following occurrences make no
difference.
.IP "--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, may not work
on all servers but enable more functionality in a better way than the
traditional PORT command. (Aded in 7.10.5)

If this option is used several times, each occurrence will toggle this on/off.
.IP "--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.

If this option is used several times, each occurrence will toggle this on/off.
.IP "-D/--dump-header <file>"
Write the protocol headers to the specified file.

This option is handy to use when you want to store the headers that a HTTP
site sends to you. Cookies from the headers could then be read in a second
curl invoke by using the \fI-b/--cookie\fP option! The \fI-c/--cookie-jar\fP
option is however a better way to store cookies.

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

If this option is used several times, the last one will be used.
.IP "-e/--referer <URL>"
(HTTP) Sends the "Referer Page" information to the HTTP server. This can also
be set with the \fI-H/--header\fP flag of course.  When used with
\fI-L/--location\fP you can append ";auto" to the 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 don't set an initial referer.

If this option is used several times, the last one will be used.
.IP "--environment"
(RISC OS ONLY) Sets a range of environment variables, using the names the -w
option supports, to easier allow extraction of useful information after having
run curl.

If this option is used several times, each occurrence will toggle this on/off.
.IP "--egd-file <file>"
(HTTPS) Specify the path name to the Entropy Gathering Daemon socket. The
socket is used to seed the random engine for SSL connections. See also the
\fI--random-file\fP option.
.IP "-E/--cert <certificate[:password]>"
(HTTPS)
Tells curl to use the specified certificate file when getting a file
with HTTPS. The certificate must be in PEM format.
If the optional password isn't specified, it will be queried for on
the terminal. Note that this certificate is the private key and the private
certificate concatenated!

If this option is used several times, the last one will be used.
.IP "--cert-type <type>"
(SSL) Tells curl what certificate type the provided certificate is in. PEM,
DER and ENG are recognized types.

If this option is used several times, the last one will be used.
.IP "--cacert <CA certificate>"
(HTTPS) 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.

curl recognizes the environment variable named 'CURL_CA_BUNDLE' if that 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 this option is used several times, the last one will be used.
.IP "--capath <CA certificate directory>"
(HTTPS) Tells curl to use the specified certificate directory to verify the
peer. The certificates must be in PEM format, and the directory must have been
processed using the c_rehash utility supplied with openssl. Using
\fI--capath\fP can allow curl to make https connections much more efficiently
than using \fI--cacert\fP if the \fI--cacert\fP file contains many CA
certificates.

If this option is used several times, the last one will be used.
.IP "-f/--fail"
(HTTP) Fail silently (no output at all) on server errors. This is mostly done
like this to better enable scripts etc to better deal with failed attempts. In
normal cases when a HTTP server fails to deliver a document, it returns a HTML
document stating so (which often also describes why and more). This flag will
prevent curl from outputting that and fail silently instead.

If this option is used twice, the second will again disable silent failure.
.IP "--ftp-create-dirs"
(FTP) When an FTP URL/operation uses a path that doesn't currently exist on
the server, the standard behavior of curl is to fail. Using this option, curl
will instead attempt to create missing directories. (Added in 7.10.7)

If this option is used twice, the second will again disable silent failure.
.IP "--ftp-pasv"
(FTP) Use PASV when transfering. PASV is the internal default behavior, but
using this option can be used to override a previos --ftp-port option. (Added
in 7.11.0)

If this option is used twice, the second will again disable silent failure.
.IP "--ftp-ssl"
(FTP) Make the FTP connection switch to use SSL/TLS. (Added in 7.11.0)

If this option is used twice, the second will again disable silent failure.
.IP "-F/--form <name=content>"
(HTTP) 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 RFC1867. This enables uploading of binary
files etc. To force the 'content' part to be 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 letter <. 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.

Example, to send your password file to the server, where
\&'password' is the name of the form-field to which /etc/passwd will be the
input:

\fBcurl\fP -F password=@/etc/passwd www.mypasswords.com

To read the file's content from stdin insted of a file, use - where the file
name should've been. This goes for both @ and < constructs.

You can also tell curl what Content-Type to use for the file upload part, by
using 'type=', in a manner similar to:

\fBcurl\fP -F "web=@index.html;type=text/html" url.com

See further examples and details in the MANUAL.

This option can be used multiple times.
.IP "-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 them being
interpreted by curl itself. Note that these letters are not normal legal URL
contents but they should be encoded according to the URI standard.
.IP "-G/--get"
When used, this option will make all data specified with \fI-d/--data\fP or
\fI--data-binary\fP to be used in a 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, the POST data will instead be appended to the
URL with a HEAD request.

If used multiple times, nothing special happens.
.IP "-h/--help"
Usage help.
.IP "-H/--header <header>"
(HTTP) Extra header to use when getting a web page. 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're doing. Replacing an
internal header with one without content on the right side of the colon will
prevent that header from appearing.

See also the \fI-A/--user-agent\fP and \fI-e/--referer\fP options.

This option can be used multiple times to add/replace/remove multiple headers.
.IP "-i/--include"
(HTTP)
Include the HTTP-header in the output. The HTTP-header includes things
like server-name, date of the document, HTTP-version and more...

If this option is used twice, the second will again disable header include.
.IP "--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 http://www.netscape.com/

If this option is used several times, the last one will be used.
.IP "-I/--head"
(HTTP/FTP/FILE)
Fetch the HTTP-header only! HTTP-servers feature the command HEAD
which this uses to get nothing but the header of a document. When used
on a FTP or FILE file, curl displays the file size and last modification
time only.

If this option is used twice, the second will again disable header only.
.IP "-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 basicly have the same effect
as if a new session is started. Typical browsers always discard session
cookies when they're closed down. (Added in 7.9.7)

If this option is used several times, each occurrence will toggle this on/off.
.IP "-k/--insecure"
(SSL) This option explicitly allows curl to perform "insecure" SSL connections
and transfers. Starting with curl 7.10, all SSL connections will be attempted
to be made secure by using the CA certificate bundle installed by
default. This makes all connections considered "insecure" to fail unless
\fI-k/--insecure\fP is used.

If this option is used twice, the second time will again disable it.
.IP "--key <key>"
(SSL) Private key file name. Allows you to provide your private key in this
separate file.

If this option is used several times, the last one will be used.
.IP "--key-type <type>"
(SSL) Private key file type. Specify which type your \fI--key\fP provided
private key is. DER, PEM and ENG are supported.

If this option is used several times, the last one will be used.
.IP "--krb4 <level>"
(FTP) Enable kerberos4 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.

This option requiures that the library was built with kerberos4 support. This
is not very common. Use \fI-V/--version\fP to see if your curl supports it.

If this option is used several times, the last one will be used.
.IP "-K/--config <config file>"
Specify which config file to read curl arguments from. The config file is a
text file in which command line arguments can be written which then will be
used as if they were written on the actual command line. Options and their
parameters must be specified on the same config file line. If the parameter is
to contain white spaces, the parameter must be inclosed within quotes.  If the
first column of a config line is a '#' character, the rest of the line will be
treated as a comment.

Specify the filename 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 \fI--url\fP option, and not by simply writing the URL on its own
line. So, it could look similar to this:

url = "http://curl.haxx.se/docs/"

This option can be used multiple times.
.IP "--limit-rate <speed>"
Specify the maximum transfer rate you want curl to use. This feature is useful
if you have a limited pipe and you'd like your transfer not use your entire
bandwidth.

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. Examples: 200K, 3m and 1G.

If you are also using the \fI-Y/--speed-limit\fP option, that option will take
precedence and might cripple the rate-limiting slightly, to help keeping the
speed-limit logic working.

This option was introduced in curl 7.10.

If this option is used several times, the last one will be used.
.IP "-l/--list-only"
(FTP)
When listing an FTP directory, this switch forces a name-only view.
Especially useful if you want to machine-parse the contents of an FTP
directory since the normal directory view doesn't use a standard look
or format.

This option causes an FTP NLST command to be sent.  Some FTP servers
list only files in their response to NLST; they do not include
subdirectories and symbolic links.

If this option is used twice, the second will again disable list only.
.IP "-L/--location"
(HTTP/HTTPS) If the server reports that the requested page has a different
location (indicated with the header line Location:) this flag will let curl
attempt to reattempt the get on the new place. If used together with
\fI-i/--include\fP or \fI-I/--head\fP, headers from all requested pages will
be shown. If authentication is used, curl will only send its credentials to
the initial host, so if a redirect takes curl to a different host, it won't
intercept the user+password. See also \fI--location-trusted\fP on how to
change this.

If this option is used twice, the second will again disable location following.
.IP "--location-trusted"
(HTTP/HTTPS) Like \fI-L/--location\fP, 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 do a site to which
you'll send your authentication info (which is plaintext in the case of HTTP
Basic authentication).

If this option is used twice, the second will again disable location following.
.IP "--max-filesize <bytes>"
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.

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. This concerns both FTP and HTTP transfers.
.IP "-m/--max-time <seconds>"
Maximum time in seconds that you allow the whole operation to take.  This is
useful for preventing your batch jobs from hanging for hours due to slow
networks or links going down.  This doesn't work fully in win32 systems.  See
also the \fI--connect-timeout\fP option.

If this option is used several times, the last one will be used.
.IP "-M/--manual"
Manual. Display the huge help text.
.IP "-n/--netrc"
Makes curl scan the \fI.netrc\fP 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
.BR netrc(4)
or
.BR ftp(1)
for details on the file format. Curl will not complain if that file
hasn't the right permissions (it should not be world nor group
readable). The environment variable "HOME" is used to find the home
directory.

A quick and very simple example of how to setup a \fI.netrc\fP to allow curl
to ftp to the machine host.domain.com with user name \&'myself' and password
'secret' should look similar to:

.B "machine host.domain.com login myself password secret"

If this option is used twice, the second will again disable netrc usage.
.IP "--netrc-optional"
Very similar to \fI--netrc\fP, but this option makes the .netrc usage
\fBoptional\fP and not mandatory as the \fI--netrc\fP does.
.IP "--negotiate"
(HTTP) Enables GSS-Negotiate authentication. The GSS-Negotiate method was
designed by Microsoft and is used in their web aplications. It is primarily
meant as a support for Kerberos5 authentication but may be also used along
with another authentication methods. For more information see IETF draft
draft-brezak-spnego-http-04.txt. (Added in 7.10.6)

This option requiures that the library was built with GSSAPI support. This is
not very common. Use \fI-V/--version\fP to see if your version supports
GSS-Negotiate.

If this option is used several times, the following occurrences make no
difference.
.IP "-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.

If this option is used twice, the second will again switch on buffering.
.IP "--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, reversed 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. (Added in 7.10.6)

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

This option requiures that the library was built with SSL support. Use
\fI-V/--version\fP to see if your curl supports NTLM.

If this option is used several times, the following occurrences make no
difference.
.IP "-o/--output <file>"
Write output to <file> instead of stdout. If you are using {} or [] to fetch
multiple documents, 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}.site.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 you have number of URLs.

See also the \fI--create-dirs\fP option to create the local directories
dynamically.
.IP "-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.)

You may use this option as many times as you have number of URLs.
.IP "--pass <phrase>"
(SSL) Pass phrase for the private key

If this option is used several times, the last one will be used.
.IP "--proxy-ntlm"
Tells curl to use NTLM authentication when communicating with the given
proxy. Use \fI--ntlm\fP for enabling NTLM with a remote host.

If this option is used twice, the second will again disable proxy NTLM.
.IP "-p/--proxytunnel"
When an HTTP proxy is used (\fI-x/--proxy\fP), this option will cause non-HTTP
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 "-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 practice, 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 "-"
(any single-letter string) to make it pick the machine's default
.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 \fI$HOME/.curlrc\fP
file will not be read and used as a config file.
.IP "-Q/--quote <comand>"
(FTP) Send an arbitrary command to the remote FTP server, by using the QUOTE
command of the server. Not all servers support this command, and the set of
QUOTE commands are server specific! Quote commands are sent BEFORE the
transfer is taking place. To make commands take place after a successful
transfer, prefix them with a dash '-'. You may specify any amount of commands
to be run before and after the transfer. If the server returns failure for one
of the commands, the entire operation will be aborted.

This option can be used multiple times.
.IP "--random-file <file>"
(HTTPS) 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!

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 "-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 "-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 mute.
.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 "--socks <host[:port]>"
Use the specified SOCKS5 proxy. If the port number is not specified, it is
assumed at port 1080. (Option 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.
.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 "-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.

Before 7.10.8, when this option was used several times, the last one was used.

In curl 7.10.8 and later, 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. (Added in
7.9.7)
.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. (Added in
7.9.7)
.IP "-u/--user <user:password>"
Specify user and password to use for server authentication.

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 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 data sent by curl, '<' means data received by curl
that is hidden in normal cases and lines starting with '*' means additional
info provided by curl.

Note that if you want to see 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 authenticaion is supported.
.IP "GSS-Negotiate"
Negotiate authenticaion 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 authenticaion is supported.
.IP "Largefile"
This curl supports transfers of large files, files larger than 2GB.
.RE
.IP "-w/--write-out <format>"
Defines what to display 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 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_starttransfer
The time, in seconds, it took from the start until the first byte is just about
to be transfered. 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. (Added in 7.9.5)
.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.

\fBNote\fP that all operations that are performed over a HTTP proxy will
transparantly 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 done with the \fI-p/--proxytunnel\fP option.

If this option is used several times, the last one will be used.
.IP "-X/--request <command>"
(HTTP)
Specifies a custom request to use when communicating with the HTTP server.
The specified request will be used instead of the standard GET. Read the
HTTP 1.1 specification for details and explanations.

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

If this option is used several times, the last one will be used.
.IP "-y/--speed-time <time>"
If a download is slower than speed-limit bytes per second during a speed-time
period, the download gets aborted. If speed-time is used, the default
speed-limit will be 1 unless set with -y.

This option controls transfers and thus will not affect slow connects etc. If
this is a concern for you, try the \fI--connect-timeout\fP option.

If this option is used several times, the last one will be used.
.IP "-Y/--speed-limit <speed>"
If a download is slower than this given speed, in bytes per second, for
speed-time seconds it gets aborted. speed-time is set with -Y and is 30 if
not set.

If this option is used several times, the last one will be used.
.IP "-z/--time-cond <date expression>"
(HTTP)
Request to get 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 doesn't match any internal ones, it
tries to get the time from a given file name instead! See the
.BR "GNU date(1)"
or
.BR "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 this option is used several times, the last one will be used.
.IP "-Z/--max-redirs <num>"
Set maximum number of redirection-followings allowed. If \fI-L/--location\fP
is used, this option can be used to prevent curl from following redirections
\&"in absurdum".

If this option is used several times, the last one will be used.
.IP "-0/--http1.0"
(HTTP) Forces curl to issue its requests using HTTP 1.0 instead of using its
internally preferred: HTTP 1.1.
.IP "-1/--tlsv1"
(HTTPS)
Forces curl to use TSL version 1 when negotiating with a remote TLS server.
.IP "-2/--sslv2"
(HTTPS)
Forces curl to use SSL version 2 when negotiating with a remote SSL server.
.IP "-3/--sslv3"
(HTTPS)
Forces curl to use SSL version 3 when negotiating with a remote SSL server.
.IP "-4/--ipv4"
If libcurl is capable of resolving an address to multiple IP versions (which
it is if it is ipv6-capable), this option tells libcurl to resolve names to
IPv4 addresses only. (Added in 7.10.8)
.IP "-6/--ipv6"
If libcurl is capable of resolving an address to multiple IP versions (which
it is if it is ipv6-capable), this option tells libcurl to resolve names to
IPv6 addresses only. (Added in 7.10.8)
.IP "-#/--progress-bar"
Make curl display progress information as a progress bar instead of the
default statistics.

If this option is used twice, the second will again disable the progress bar.
.SH FILES
.I ~/.curlrc
.RS
Default config file.

.SH ENVIRONMENT
.IP "http_proxy [protocol://]<host>[:port]"
Sets proxy server to use for HTTP.
.IP "HTTPS_PROXY [protocol://]<host>[:port]"
Sets proxy server to use for HTTPS.
.IP "FTP_PROXY [protocol://]<host>[:port]"
Sets proxy server to use for FTP.
.IP "GOPHER_PROXY [protocol://]<host>[:port]"
Sets proxy server to use for GOPHER.
.IP "ALL_PROXY [protocol://]<host>[:port]"
Sets proxy server to use if no protocol-specific proxy is set.
.IP "NO_PROXY <comma-separated list of hosts>"
list of host names that shouldn't go through any proxy. If set to a asterisk
'*' only, it matches all hosts.
.SH EXIT CODES
There exists a bunch of different error codes and their corresponding error
messages that may appear during bad conditions. At the time of this writing,
the exit codes are:
.IP 1
Unsupported protocol. This build of curl has no support for this protocol.
.IP 2
Failed to initialize.
.IP 3
URL malformat. The syntax was not correct.
.IP 4
URL user malformatted. The user-part of the URL syntax was not correct.
.IP 5
Couldn't resolve proxy. The given proxy host could not be resolved.
.IP 6
Couldn't resolve host. The given remote host was not resolved.
.IP 7
Failed to connect to host.
.IP 8
FTP weird server reply. The server sent data curl couldn't parse.
.IP 9
FTP access denied. The server denied login.
.IP 10
FTP user/password incorrect. Either one or both were not accepted by the
server.
.IP 11
FTP weird PASS reply. Curl couldn't parse the reply sent to the PASS request.
.IP 12
FTP weird USER reply. Curl couldn't parse the reply sent to the USER request.
.IP 13
FTP weird PASV reply, Curl couldn't parse the reply sent to the PASV request.
.IP 14
FTP weird 227 format. Curl couldn't parse the 227-line the server sent.
.IP 15
FTP can't get host. Couldn't resolve the host IP we got in the 227-line.
.IP 16
FTP can't reconnect. Couldn't connect to the host we got in the 227-line.
.IP 17
FTP couldn't set binary. Couldn't change transfer method to binary.
.IP 18
Partial file. Only a part of the file was transfered.
.IP 19
FTP couldn't download/access the given file, the RETR (or similar) command
failed.
.IP 20
FTP write error. The transfer was reported bad by the server.
.IP 21
FTP quote error. A quote command returned error from the server.
.IP 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 \fI-f/--fail\fP is used.
.IP 23
Write error. Curl couldn't write data to a local filesystem or similar.
.IP 24
Malformed user. User name badly specified.
.IP 25
FTP couldn't STOR file. The server denied the STOR operation, used for FTP
uploading.
.IP 26
Read error. Various reading problems.
.IP 27
Out of memory. A memory allocation request failed.
.IP 28
Operation timeout. The specified time-out period was reached according to the
conditions.
.IP 29
FTP couldn't set ASCII. The server returned an unknown reply.
.IP 30
FTP PORT failed. The PORT command failed. Not all FTP servers support the PORT
command, try doing a transfer using PASV instead!
.IP 31
FTP couldn't use REST. The REST command failed. This command is used for
resumed FTP transfers.
.IP 32
FTP couldn't use SIZE. The SIZE command failed. The command is an extension
to the original FTP spec RFC 959.
.IP 33
HTTP range error. The range "command" didn't work.
.IP 34
HTTP post error. Internal post-request generation error.
.IP 35
SSL connect error. The SSL handshaking failed.
.IP 36
FTP bad download resume. Couldn't continue an earlier aborted download.
.IP 37
FILE couldn't read file. Failed to open the file. Permissions?
.IP 38
LDAP cannot bind. LDAP bind operation failed.
.IP 39
LDAP search failed.
.IP 40
Library not found. The LDAP library was not found.
.IP 41
Function not found. A required LDAP function was not found.
.IP 42
Aborted by callback. An application told curl to abort the operation.
.IP 43
Internal error. A function was called with a bad parameter.
.IP 44
Internal error. A function was called in a bad order.
.IP 45
Interface error. A specified outgoing interface could not be used.
.IP 46
Bad password entered. An error was signaled when the password was entered.
.IP 47
Too many redirects. When following redirects, curl hit the maximum amount.
.IP 48
Unknown TELNET option specified.
.IP 49
Malformed telnet option.
.IP 51
The remote peer's SSL certificate wasn't ok
.IP 52
The server didn't reply anything, which here is considered an error.
.IP 53
SSL crypto engine not found
.IP 54
Cannot set SSL crypto engine as default
.IP 55
Failed sending network data
.IP 56
Failure in receiving network data
.IP 57
Share is in use (internal error)
.IP 58
Problem with the local certificate
.IP 59
Couldn't use specified SSL cipher
.IP 60
Problem with the CA cert (path? permission?)
.IP 61
Unrecognized transfer encoding
.IP 62
Invalid LDAP URL
.IP 63
Maximum file size exceeded
.IP XX
There will appear more error codes here in future releases. The existing ones
are meant to never change.
.SH AUTHORS / CONTRIBUTORS
Daniel Stenberg is the main author, but the whole list of contributors is
found in the separate THANKS file.
.SH WWW
http://curl.haxx.se
.SH FTP
ftp://ftp.sunet.se/pub/www/utilities/curl/
.SH "SEE ALSO"
.BR ftp (1),
.BR wget (1),
.BR snarf (1)