curl - phpMan

curl(1) Curl Manual curl(1)

NAME
curl - transfer a URL

SYNOPSIS
curl [options] [URL...]

DESCRIPTION
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 libcurl(3) for
details.

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, but you can use several
ones next to each other:

http://any.org/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.

Curl will attempt to re-use connections for multiple file transfers, so that get-
ting 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.

OPTIONS
-a/--append
(FTP) When used in an FTP upload, this will tell curl to append to the tar-
get 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.

-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 -H/--header option of course.

If this option is set more than once, the last one will be the one that's
used.

--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 authentica-
tion method, which you can do with --basic, --digest, --ntlm, and --negoti-
ate. (Added in 7.10.6)

Note that 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.

If this option is used several times, the following occurrences make no dif-
ference.

-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 ses-
sion 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 -L/--location option. The file
format of the file to read cookies from should be plain HTTP headers or the
Netscape/Mozilla cookie file format.

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

If this option is set more than once, the last one will be the one that's
used.

-B/--use-ascii
Enable ASCII transfer when using FTP or LDAP. 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.

--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 --ntlm,
--digest and --negotiate). (Added in 7.10.6)

If this option is used several times, the following occurrences make no dif-
ference.

--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:
http://www.openssl.org/docs/apps/ciphers.html

If this option is used several times, the last one will override the others.

--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.

--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 -m/--max-time option.

If this option is used several times, the last one will be used.

-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.

NOTE If the cookie jar can't be created or written to, the whole curl opera-
tion 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 specified file name will be
used.

-C/--continue-at <offset>
Continue/Resume a previous file transfer at the given offset. The given off-
set is the exact number of bytes that will be skipped counted 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 this option is used several times, the last one will be used.

--create-dirs
When used in conjunction with the -o option, curl will create the necessary
local directory hierarchy as needed. This option creates the dirs mentioned
with the -o option, nothing else. If the -o file name uses no dir or if the
dirs it mentions already exist, no dir will be created.

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

--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.

-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 con-
tent-type application/x-www-form-urlencoded. Compare to -F/--form. 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
--data @foobar".

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

-d/--data is the same as --data-ascii.

If this option is used several times, the ones following the first will
append data.

--data-ascii <data>
(HTTP) This is an alias for the -d/--data option.

If this option is used several times, the ones following the first will
append data.

--data-binary <data>
(HTTP) This posts data in a similar manner as --data-ascii 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
--data-ascii option, this is for you.

If this option is used several times, the ones following the first will
append data.

--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 -u/--user option to set user name and pass-
word. See also --ntlm, --negotiate and --anyauth for related options. (Added
in curl 7.10.6)

If this option is used several times, the following occurrences make no dif-
ference.

--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. (Added in 7.10.5)

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

--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.

-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 -b/--cookie option! The -c/--cookie-jar option is
however a better way to store cookies.

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

If this option is used several times, the last one will be used.

-e/--referer <URL>
(HTTP) Sends the "Referer 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 referer URL to make curl auto-
matically 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.

--engine <name>
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 (or
none) of the engines may be available at run-time.

--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 hav-
ing run curl.

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

--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
--random-file option.

-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 cer-
tificate is the private key and the private certificate concatenated!

If this option is used several times, the last one will be used.

--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.

--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.

--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
--capath can allow curl to make https connections much more efficiently than
using --cacert if the --cacert file contains many CA certificates.

If this option is used several times, the last one will be used.

-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.

--ftp-account [data]
(FTP) When an FTP server asks for "account data" after user name and pass-
word has been provided, this data is sent off using the ACCT command. (Added
in 7.13.0)

If this option is used twice, the second will override the previous use.

--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.

--ftp-pasv
(FTP) Use PASV when transfering. PASV is the internal default behavior, but
using this option can be used to override a previous --ftp-port option.
(Added in 7.11.0)

If this option is used twice, the second will again disable silent failure.

--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 this.

-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 mul-
tipart/form-data according to RFC1867. 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 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:

curl -F password=@/etc/passwd www.mypasswords.com

To read the file's content from stdin instead 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 by using 'type=', in a man-
ner similar to:

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

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

You can also explicitly change the name field of an file upload part by set-
ting filename=, like this:

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

See further examples and details in the MANUAL.

This option can be used multiple times.

-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 nor-
mal legal URL contents but they should be encoded according to the URI stan-
dard.

-G/--get
When used, this option will make all data specified with -d/--data or
--data-binary 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.

-h/--help
Usage help.

-H/--header <header>
(HTTP) Extra header to use when getting a web page. You may specify any num-
ber 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 -A/--user-agent and -e/--referer options.

This option can be used multiple times to add/replace/remove multiple head-
ers.

-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.

--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.

-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.

-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 ses-
sion 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.

-k/--insecure
(SSL) This option explicitly allows curl to perform "insecure" SSL connec-
tions 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
-k/--insecure is used.

If this option is used twice, the second time will again disable it.

--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.

--key-type <type>
(SSL) Private key file type. Specify which type your --key provided private
key is. DER, PEM and ENG are supported.

If this option is used several times, the last one will be used.

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

If this option is used several times, the last one will be used.

-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 spec-
ify it using the --url 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.

--limit-rate <speed>
Specify the maximum transfer rate you want curl to use. This feature is use-
ful 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 -Y/--speed-limit 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.

-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 direc-
tory 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.

-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
-i/--include or -I/--head, headers from all requested pages will be shown.
If authentication is used, curl will only send its credentials to the ini-
tial host, so if a redirect takes curl to a different host, it won't inter-
cept the user+password. See also --location-trusted on how to change this.

If this option is used twice, the second will again disable location follow-
ing.

--location-trusted
(HTTP/HTTPS) 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 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 follow-
ing.

--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.

-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 --connect-timeout option.

If this option is used several times, the last one will be used.

-M/--manual
Manual. Display the huge help text.

-n/--netrc
Makes curl scan the .netrc file in the user's home directory for login name
and password. This is typically used for ftp on unix. If used with http,
curl will enable user authentication. See netrc(4) or ftp(1) for details on
the file format. Curl will not complain if that file hasn't the right per-
missions (it should not be world nor group readable). The environment vari-
able "HOME" is used to find the home directory.

A quick and very 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

machine host.domain.com login myself password secret

If this option is used twice, the second will again disable netrc usage.

--netrc-optional
Very similar to --netrc, but this option makes the .netrc usage optional and
not mandatory as the --netrc does.

--negotiate
(HTTP) Enables GSS-Negotiate authentication. The GSS-Negotiate method was
designed by Microsoft and is used in their web applications. 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 requires that the library was built with GSSAPI support. This is
not very common. Use -V/--version to see if your version supports GSS-Nego-
tiate.

If this option is used several times, the following occurrences make no dif-
ference.

-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.

--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 --proxy-
ntlm.

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

If this option is used several times, the following occurrences make no dif-
ference.

-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> spec-
ifier. 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 --create-dirs option to create the local directories dynami-
cally.

-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 remote file name to use for saving is extracted from the given URL.
Nothing else

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

--pass <phrase>
(SSL) Pass phrase for the private key

If this option is used several times, the last one will be used.

--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.

If this option is used twice, the second will again disable proxy HTTP Basic
authentication.

--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.

If this option is used twice, the second will again disable proxy HTTP
Digest.

--proxy-ntlm
Tells curl to use HTTP NTLM authentication when communicating with the given
proxy. Use --ntlm for enabling NTLM with a remote host.

If this option is used twice, the second will again disable proxy HTTP NTLM.

-p/--proxytunnel
When an HTTP proxy is used (-x/--proxy), 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.

-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:

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

IP address
i.e "192.168.10.1" to specify exact IP number

host name
i.e "my.host.domain" to specify machine

- (any single-letter string) to make it pick the machine's default

If this option is used several times, the last one will be used. 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++.

-q If used as the first parameter on the command line, the $HOME/.curlrc file
will not be read and used as a config file.

-Q/--quote <comand>
(FTP) Send an arbitrary command to the remote FTP server. Quote commands are
sent BEFORE the transfer is taking place (just after the initial PWD command
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 '+'. You may specify any amount 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.

This option can be used multiple times.

--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 --egd-file option.

-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.

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(*)(H)

500-700,600-799
specifies 300 bytes from offset 500(H)

100-199,500-599
specifies two separate 100 bytes ranges(*)(H)

(*) = 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 doc-
ument.

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.

-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.

--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 --retry-delay you disable this exponential backoff algo-
rithm. See also --retry-max-time to limit the total time allowed for
retries. (Option added in 7.12.3)

If this option is used multiple times, the last occurrence decide the
amount.

--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 --retry is also used.
Setting this delay to zero will make curl use the default backoff time.
(Option added in 7.12.3)

If this option is used multiple times, the last occurrence decide the
amount.

--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 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 -m/--max-time. Set
this option to zero to not timeout retries. (Option added in 7.12.3)

If this option is used multiple times, the last occurrence decide the
amount.

-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.

-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.

--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 -x/--proxy, as they are mutually
exclusive.

If this option is used several times, the last one will be used.

--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.

--tcp-nodelay
Turn on the TCP_NODELAY option. See the curl_easy_setopt(3) 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.

-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/--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 oper-
ation 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/

--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)

--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 --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.

If this option is used several times, the last one will be used. (Added in
7.9.7)

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

If this option is used several times, the last one will be used.

-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.

--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 -o/--output or the -O/--remote-name options.

-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 addi-
tional info provided by curl.

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

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

If this option is used twice, the second will again disable verbose.

-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:

IPv6 You can use IPv6 with this.

krb4 Krb4 for ftp is supported.

SSL HTTPS and FTPS are supported.

libz Automatic decompression of compressed files over HTTP is supported.

NTLM NTLM authentication is supported.

GSS-Negotiate
Negotiate authentication is supported.

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

AsynchDNS
This curl uses asynchronous name resolves.

SPNEGO SPNEGO Negotiate authentication is supported.

Largefile
This curl supports transfers of large files, files larger than 2GB.

IDN This curl supports IDN - international domain names.

-w/--write-out <format>
Defines what to display after a completed and successful operation. The for-
mat is a string that may contain plain text mixed with any number of vari-
ables. The string can be specified as "string", to get read from a particu-
lar 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 speci-
fied 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.

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:

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

http_code The numerical code that was found in the last retrieved
HTTP(S) page.

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)

time_total The total time, in seconds, that the full operation lasted.
The time will be displayed with millisecond resolution.

time_namelookup
The time, in seconds, it took from the start until the name
resolving was completed.

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

time_pretransfer
The time, in seconds, it took from the start until the file
transfer is just about to begin. This includes all pre-trans-
fer commands and negotiations that are specific to the par-
ticular protocol(s) involved.

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 com-
plete execution time for multiple redirections. (Added in
7.12.3)

time_starttransfer
The time, in seconds, it took from the start until the first
byte is just about to be transferred. This includes time_pre-
transfer and also the time the server needs to calculate the
result.

size_download The total amount of bytes that were downloaded.

size_upload The total amount of bytes that were uploaded.

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.

speed_download The average download speed that curl measured for the com-
plete download.

speed_upload The average upload speed that curl measured for the complete
upload.

content_type The Content-Type of the requested document, if there was any.
(Added in 7.9.5)

num_connects Number of new connects made in the recent transfer. (Added in
7.12.3)

num_redirects Number of redirects that were followed in the request. (Added
in 7.12.3)

If this option is used several times, the last one will be used.

-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.

Note that all operations that are performed over a HTTP proxy will transpar-
ently 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 -p/--proxytunnel option.

If this option is used several times, the last one will be used.

-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.

-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 --connect-timeout option.

If this option is used several times, the last one will be used.

-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.

-z/--time-cond <date expression>
(HTTP) 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 doesn't match any internal ones,
it tries to get the time from a given file name instead! See the curl_get-
date(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.

--max-redirs <num>
Set maximum number of redirection-followings allowed. If -L/--location 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.

-0/--http1.0
(HTTP) Forces curl to issue its requests using HTTP 1.0 instead of using its
internally preferred: HTTP 1.1.

-1/--tlsv1
(HTTPS) Forces curl to use TSL version 1 when negotiating with a remote TLS
server.

-2/--sslv2
(HTTPS) Forces curl to use SSL version 2 when negotiating with a remote SSL
server.

-3/--sslv3
(HTTPS) Forces curl to use SSL version 3 when negotiating with a remote SSL
server.

--3p-quote
(FTP) Specify arbitrary commands to send to the source server. See the
-Q/--quote option for details. (Added in 7.13.0)

--3p-url
(FTP) Activates a FTP 3rd party transfer. Specifies the source URL to get a
file from, while the "normal" URL will be used as target URL, the file that
will be written/created.

Note that not all FTP server allow 3rd party transfers. (Added in 7.13.0)

--3p-user
(FTP) Specify user:password for the source URL transfer. (Added in 7.13.0)

-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)

-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)

-#/--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.

FILES
~/.curlrc
Default config file.

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

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

FTP_PROXY [protocol://]<host>[:port]
Sets proxy server to use for FTP.

GOPHER_PROXY [protocol://]<host>[:port]
Sets proxy server to use for GOPHER.

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

NO_PROXY <comma-separated list of hosts>
list of host names that shouldn't go through any proxy. If set to a asterisk

EXIT CODES
There exists a bunch of different error codes and their corresponding error mes-
sages that may appear during bad conditions. At the time of this writing, the exit
codes are:

1 Unsupported protocol. This build of curl has no support for this protocol.

2 Failed to initialize.

3 URL malformat. The syntax was not correct.

4 URL user malformatted. The user-part of the URL syntax was not correct.

5 Couldn't resolve proxy. The given proxy host could not be resolved.

6 Couldn't resolve host. The given remote host was not resolved.

7 Failed to connect to host.

8 FTP weird server reply. The server sent data curl couldn't parse.

9 FTP access denied. The server denied login.

10 FTP user/password incorrect. Either one or both were not accepted by the
server.

11 FTP weird PASS reply. Curl couldn't parse the reply sent to the PASS
request.

12 FTP weird USER reply. Curl couldn't parse the reply sent to the USER
request.

13 FTP weird PASV reply, Curl couldn't parse the reply sent to the PASV
request.

14 FTP weird 227 format. Curl couldn't parse the 227-line the server sent.

15 FTP can't get host. Couldn't resolve the host IP we got in the 227-line.

16 FTP can't reconnect. Couldn't connect to the host we got in the 227-line.

17 FTP couldn't set binary. Couldn't change transfer method to binary.

18 Partial file. Only a part of the file was transferred.

19 FTP couldn't download/access the given file, the RETR (or similar) command
failed.

20 FTP write error. The transfer was reported bad by the server.

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 couldn't write data to a local filesystem or similar.

24 Malformed user. User name badly specified.

25 FTP couldn't 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.

29 FTP couldn't set ASCII. The server returned an unknown reply.

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 couldn't use REST. The REST command failed. This command is used for
resumed FTP transfers.

32 FTP couldn't use SIZE. The SIZE command failed. The command is an extension
to the original FTP spec RFC 959.

33 HTTP range error. The range "command" didn't work.

34 HTTP post error. Internal post-request generation error.

35 SSL connect error. The SSL handshaking failed.

36 FTP bad download resume. Couldn't continue an earlier aborted download.

37 FILE couldn't read file. Failed to open the file. Permissions?

38 LDAP cannot bind. LDAP bind operation failed.

39 LDAP search failed.

40 Library not found. The LDAP library was not found.

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.

44 Internal error. A function was called in a bad order.

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

46 Bad password entered. An error was signaled when the password was entered.

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

48 Unknown TELNET option specified.

49 Malformed telnet option.

51 The remote peer's SSL certificate wasn't ok

52 The server didn't 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

57 Share is in use (internal error)

58 Problem with the local certificate

59 Couldn't use specified SSL cipher

60 Problem with the CA cert (path? permission?)

61 Unrecognized transfer encoding

62 Invalid LDAP URL

63 Maximum file size exceeded

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

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

WWW
http://curl.haxx.se

FTP
ftp://ftp.sunet.se/pub/www/utilities/curl/