curl is a tool to transfer data from or to a server, using one
of the supported protocols (HTTP, HTTPS, FTP, FTPS, TFTP, DICT,
TELNET, LDAP or FILE). The command is designed to work without
user interaction.
| -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. |
| -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 authentication method, which you can
do with --basic, --digest, --ntlm, and --negotiate. 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 difference. |
| -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 -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).
If this option is used several times, the following
occurrences make no difference. |
| --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 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 specified
file name will be used. |
| -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 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 several
times, the following occurrences make no difference. |
| -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
-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 @foo-bar".
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 password. See also --ntlm, --negoti- ate and
--anyauth for related options.
If this option is used several times, the following
occurrences make no difference. |
| --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.
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 "headers" 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
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. |
| --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 having 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 certificate 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 an HTML document stating so
(which often also describes why and more). This flag will
prevent curl from outputting that and return error 22.
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 password 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.
If this option is used twice, the second will again disable
directory creation. |
| --ftp-method
[method] |
(FTP) Control what method curl
should use to reach a file on a FTP(S) server. The method
argument should be one of the following alternatives:
multicwd
curl does a single CWD operation for each path part in the
given URL. For deep hierarchies this means very many
commands. This is how RFC1738 says it should be done. This
is the default but the slowest behavior.
nocwd curl does no CWD at all. curl will do SIZE, RETR,
STOR
etc and give a full path to the server for all these
commands. This is the fastest behavior.
singlecwd
curl does one CWD with the full target directory and then
operates on the file "normally" (like in the multicwd case).
This is somewhat more standards compliant than 'nocwd' but
without the full penalty of 'multicwd'. |
| --ftp-pasv |
(FTP) Use PASV when
transferring. 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 several times, the following
occurrences make no difference. |
|
--ftp-alternative-to-user <command> |
(FTP) If authenticating with the
USER and PASS commands fails, send this command. When
connecting to Tumbleweed's Secure Transport server over FTPS
using a client certificate, using "SITE AUTH" will tell the
server to retrieve the username from the certificate. (Added
in 7.15.5) |
| --ftp-skip-pasv-ip |
(FTP) Tell curl to not use the
IP address the server suggests in its response to curl's
PASV command when curl connects the data connection. Instead
curl will re-use the same IP address it already uses for the
control connection. (Added in 7.14.2)
This option has no effect if PORT, EPRT or EPSV is used
instead of PASV.
If this option is used twice, the second will again use
the server's suggested address. |
| --ftp-ssl |
(FTP) Try to use SSL/TLS for the
FTP connection. Reverts to a non-secure connection if the
server doesn't support SSL/TLS. (Added in 7.11.0) If this
option is used twice, the second will again disable this. |
| --ftp-ssl-reqd |
(FTP) Require SSL/TLS for the
FTP connection. Terminates the connection if the server
doesn't support SSL/TLS. (Added in 7.15.5) 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
multipart/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 manner similar to:
curl -F "web=@index.html;type=text/html" url.com
or
curl -F "name=daniel;type=text/foo" url.com
You can also explicitly change the name field of an file
upload part by setting 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. |
| --form-string
<name=string> |
(HTTP) Similar to --form except
that the value string for the named parameter is used
literally. Leading '@' and '<' characters, and the ';type='
string in the value have no special meaning. Use this in
preference to --form if there's any possibility that the
string value may accidentally trigger the '@' or '<'
features of --form. |
| -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. |
| -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 this option is used several times, the following
occurrences make no difference. |
| -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. curl will make sure that each
header you add/replace get sent with the proper end of line
marker, you should thus not add that as a part of the header
content: do not add newlines or carriage returns they will
only mess things up for you.
See also the -A/--user-agent and -e/--referer options.
This option can be used multiple times to
add/replace/remove multiple headers. |
|
--ignore-content-length |
(HTTP) Ignore the Content-Length
header. This is particularly useful for servers running
Apache 1.x, which will report incorrect Content-Length for
files larger than 2 gigabytes. |
| -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 session cookies when they're closed down.
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 connections and
transfers. All SSL connections are 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 enclosed 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 --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.
When curl is invoked, it always (unless -q is used)
checks for a default config file and uses it if found. The
default config file is checked for in the following places
in this order:
1) curl tries to find the "home dir": It first checks for
the CURL_HOME and then the HOME environment variables.
Failing that, it uses getpwuid() on unix-like systems (which
returns the home dir given the current user in your system).
On Windows, it then checks for the APPDATA variable, or as a
last resort the '%USER-PROFILE%0lication Data'.
2) On windows, if there is no _curlrc file in the home
dir, it checks for one in the same dir the executable curl
is placed. On unix-like systems, it will simply try to load
.curlrc from the determined home dir. |
| --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 -Y/--speed-limit option, that
option will take precedence and might cripple the
rate-limiting slightly, to help keeping the speed-limit
logic working.
If 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 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. |
| --local-port
<num>[-num] |
Set a preferred number or range
of local port numbers to use for the connection(s). Note
that port numbers by nature is a scarce resource that will
be busy at times so setting this range to something too
narrow might cause unnecessary connection setup failures.
(Added in 7.15.2) |
| -L/--location |
(HTTP/HTTPS) If the server
reports that the requested page has moved to a different
location (indicated with a Location: header and a 3XX
response code) this option will make curl redo the request
on the new place. If used together with -i/--include or
-I/--head, headers from all requested pages will be shown.
When authentication is used, curl only sends its credentials
to the initial host. If a redirect takes curl to a different
host, it won't be able to intercept the user+password. See
also --location-trusted on how to change this. You can limit
the amount of redirects to follow by using the --max-redirs
option.
If this option is used twice, the second will again
disable location following. |
| --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 following. |
| --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. See also the
--connect-timeout option. If this option is used several
times, the last one will be used. |
| -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
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 .netrc
to allow curl to ftp to the machine host.domain.com with
user name 'myself' and password 'secret' should look similar
to:
machine host.domain.com login myself password secret
If this option is used twice, the second will again
disable netrc usage. |
| --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.
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-Negotiate.
When using this option, you must also provide a fake
-u/--user option to activate the authentication code
properly. Sending a '-u :' is enough as the user name and
password from the -u option aren't actually used.
If this option is used several times, the following
occurrences make no difference. |
| -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.
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 difference. |
| -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 --create-dirs option to create the local
directories dynamically. |
| -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-anyauth |
Tells curl to pick a suitable
authentication method when communicating with the given
proxy. This will cause an extra request/response round-trip.
(Added in 7.13.2) If this option is used twice, the second
will again disable the proxy use-any authentication. |
| --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
- make curl pick the same IP address that is already used
for the control connection
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 curlrc config file will not be read
and used. See the -K/--config for details on the default
config file search path. |
| -Q/--quote <command> |
(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 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. |
| -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
algorithm. See also --retry-max-time to limit the total time
allowed for retries. (Added in 7.12.3)
If this option is used multiple times, the last
occurrence decide the amount. |
| --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. (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 perform- ing, 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. (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 silent mode. |
| -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. |
| --socks4 <host[:port]> |
Use the specified SOCKS4 proxy.
If the port number is not specified, it is assumed at port
1080. (Added in 7.15.2)
This option overrides any previous use of -x/--proxy, as
they are mutually exclusive.
If this option is used several times, the last one will
be used. |
| --socks5 <host[:port]> |
Use the specified SOCKS5 proxy.
If the port number is not specified, it is assumed at port
1080. (Added in 7.11.1)
This option overrides any previous use of -x/--proxy, as
they are mutually exclusive.
If this option is used several times, the last one will
be used. (This option was previously wrongly documented and
used as --socks without the number appended.) |
| --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 operation to
fail. If this is used on a http(s) server, the PUT command
will be used. Use the file name "-" (a single dash) to use
stdin instead of a given file.
You can specify one -T for each URL on the command line.
Each -T + URL pair specifies what to upload and to where.
curl also sup- ports "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. |
| --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. |
| --trace-time |
Prepends a time stamp to each
trace or verbose line that curl displays. (Added in 7.14.0)
If this option is used several times, each occurrence will
toggle it on/off. |
| -u/--user <user:password> |
Specify user and password to use
for server authentication. Overrides -n/--netrc and --netrc-optional.
If you use an SSPI-enabled curl binary and do NTLM
autentication, you can force curl to pick up the user name
and password from your environment by simply specifying a
single colon with this option: "-u :".
If this option is used several times, the last one will
be used. |
| -U/--proxy-user <user:password> |
Specify user and password to use
for proxy authentication.
If you use an SSPI-enabled curl binary and do NTLM
autentication, you can force curl to pick up the user name
and password from your environment by simply specifying a
single colon with this option: "-U :".
If this option is used several times, the last one will
be used. |
| --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 "header data" sent by curl, '<'
means "header data" received by curl that is hidden in
normal cases and lines starting with '*' means additional
info provided by curl.
Note that if you only want HTTP headers in the output,
-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. |
| -w/--write-out
<format> |
Defines what to display on
stdout after a completed and successful operation. The
format is a string that may contain plain text mixed with
any number of variables. The string can be specified as
"string", to get read from a particular file you specify it
"@filename" and to tell curl to read the format from stdin
you write "@-". The variables present in the output format
will be substituted by the value or text that curl thinks
fit, as described below. All variables are specified like %{variable_name}
and to output a normal % you just write them like %%. You
can output a newline by using \n, a carriage return with \r
and a tab space with \t.
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
connect 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-transfer commands and negotiations that are specific to
the particular protocol(s) involved.
time_redirect
The time, in seconds, it took for all redirection steps
include name lookup, connect, pretransfer and transfer
before final transaction was started. time_redirect shows
the complete execution time for multiple redirections.
(Added in 7.12.3)
time_starttransfer
The time, in seconds, it took from the start until the first
byte is just about to be transferred. This includes
time_pretransfer and also the time the server needs to
calculate the result.
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
complete 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.
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)
ftp_entry_path
The initial path libcurl ended up in when logging on to the
remote FTP server. (Added in 7.15.4)
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 transparently be converted to HTTP. It means that
certain protocol specific operations might not be available.
This is not the case if you can tunnel through the proxy, as
done with the -p/--proxytunnel option.
Starting with 7.14.1, the proxy host can be specified the
exact same way as the proxy environment variables, include
protocol prefix (http://) and embedded user + password.
If this option is used several times, the last one will
be used. |
| -X/--request
<command> |
(HTTP) Specifies a custom
request method to use when communicating with the HTTP
server. The specified request will be used instead of the
method otherwise used (which defaults to 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_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. |
| --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". By default, the limit is set to
50 redirections. Set this option to -1 to make it limitless.
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. |
| -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. |
| -#/--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. |
| URL |
The URL syntax is protocol
dependent. You'll find a detailed description in RFC 3986. 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.
Since curl 7.15.1 you can also specify step counter for
the ranges, so that you can get every Nth number or letter:
http://www.numericals.com/file[1-100:10].txt
http://www.letters.com/file[a-z:2].txt
If you specify URL without protocol:// prefix, curl will
attempt to guess what protocol you might want. It will then
default to HTTP but try other protocols based on often-used
host name prefixes. For example, for host names starting
with "ftp." curl will assume you want to speak FTP.
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. |
The above command would use the curl command to
retrieve the index.htm from computerhope and save it as index.htm in
the current directory.
