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 fea-
tures. 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 lead-
ing zeros)
ftp://ftp.letters.com/file[a-z].txt
It is possible to specify up to 9 sets or series for a
URL, but no nesting is supported at the moment:
http://www.any.org/archive[1996-1999]/vol-
ume[1-4]part{a,b,c,index}.html
You can specify any amount of URLs on the command line.
They will be fetched in a sequential manner in the speci-
fied order.
Curl will attempt to re-use connections for multiple file
transfers, so that getting many files from the same server
will not do multiple connects / handshakes. This improves
speed. Of course this is only done on files specified on a
single command line and cannot be used between separate
-a/--append
(FTP) When used in an FTP upload, this will tell
curl to append to the target file instead of over-
writing 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
flag 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 authen-
tication method, which you can do with --digest,
--ntlm, and --negotiate. (Added in 7.10.6)
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 acti-
vates 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
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
Use ASCII transfer when getting an FTP file or LDAP
info. For FTP, this can also be enforced by using
an URL that ends with ";type=A". This option causes
data sent to stdout to be in text mode for win32
systems.
If this option is used twice, the second one will
disable ASCII usage.
--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 previ-
ously set option that sets a different authentica-
tion method (such as --ntlm, --digest and --negoti-
ate). (Added in 7.10.6)
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 connec-
tion. 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
(Option added in curl 7.9)
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 occur-
rence will toggle it on/off.
--connect-timeout <seconds>
Maximum time in seconds that you allow the connec-
tion 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 --max-time
option.
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. (Option added in curl 7.9)
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 warn-
ing displayed, but that is the only visible feed-
back you get about this possibly lethal situation.
If this option is used several times, the last
specfied 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 trans-
fered 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.
--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
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 applica-
tion/x-www-form-urlencoded. Compare to -F. If more
than one -d/--data option is used on the same com-
mand 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 fol-
lowing 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 fol-
lowing 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 fol-
lowing 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. (Added in
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.
(Aded in 7.10.5)
If this option is used several times, each occur-
rence will toggle this on/off.
--disable-epsv
(FTP) Tell curl to disable the use of the EPSV com-
mand 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 occur-
rence 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 cookies that a HTTP site sends to you. The
cookies could then be read in a second curl invoke
by using the -b/--cookie option!
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
(RISC OS ONLY) Sets a range of environment vari-
ables, 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 occur-
rence will toggle this on/off.
--egd-file <file>
(HTTPS) Specify the path name to the Entropy Gath-
ering 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 certifi-
cate must be in PEM format. If the optional pass-
word 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.
--cacert <CA certificate>
(HTTPS) Tells curl to use the specified certificate
file to verify the peer. The file may contain mul-
tiple 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
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.
-F/--form <name=content>
(HTTP) This lets curl emulate a filled in form in
which a user has pressed the submit button. This
causes curl to POST data using the content-type
multipart/form-data according to RFC1867. This
enables uploading of binary files etc. To force the
'content' part to be be a file, prefix the file
name with an @ sign. To just get the content part
from a file, prefix the file name with the letter
<. The difference between @ and < is then that @
makes a file get attached in the post as a file
upload, while the < makes a text field and just get
the contents for that text field from a file.
Example, to send your password file to the server,
where 'password' is the name of the form-field to
which /etc/passwd will be the input:
curl -F password=@/etc/passwd www.mypasswords.com
To read the file's content from stdin insted of a
file, use - where the file name should've been.
This goes for both @ and < constructs.
You can also tell curl what Content-Type to use for
the file upload part, by using 'type=', in a manner
similar to:
curl -F "web=@index.html;type=text/html" url.com
See further examples and details in the MANUAL.
This option can be used multiple times.
-g/--globoff
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. (Option added in
curl 7.9)
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 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 con-
tent on the right side of the colon will prevent
that header from appearing.
This option can be used multiple times to
add/replace/remove multiple headers.
-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/
will be used.
-I/--head
(HTTP/FTP) 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 file, curl displays the file size 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 basicly have the same
effect as if a new session is started. Typical
browsers always discard session cookies when
they're closed down. (Added in 7.9.7)
If this option is used several times, each occur-
rence will toggle this on/off.
-k/--insecure
(SSL) This option explicitly allows curl to perform
"insecure" SSL connections and transfers. Starting
with curl 7.10, all SSL connections will be
attempted to be made secure by using the CA cer-
tificate bundle installed by default. This makes
all connections considered "insecure" to fail
unless -k/--insecure is used.
This option is ignored if --cacert or --capath is
used!
If this option is used twice, the second time will
again disable it.
--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.
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 com-
mand line arguments can be written which then will
be used as if they were written on the actual com-
parameter is to contain white spaces, the parameter
must be inclosed within quotes. If the first col-
umn 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.
--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.
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
If used together with -i or -I, headers from all
requested pages will be shown. If authentication is
used, curl will only send its credentials to the
initial host, so if a redirect takes curl to a dif-
ferent host, it won't intercept the user+password.
See also --location-trusted on how to change this.
If this option is used twice, the second will again
disable location following.
--location-trusted
(HTTP/HTTPS) Like --location, but will allow send-
ing 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.
-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 typ-
ically 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 permis-
sions (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 pass-
word 'secret' should look similar to:
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 aplications. It is primarily
meant as a support for Kerberos5 authentication but
may be also used along with another authentication
methods. For more information see IETF draft draft-
brezak-spnego-http-04.txt. (Added in 7.10.6)
NOTE that this option requiures that the library
was built with GSSAPI support. This is not very
common. Use curl --version to see if your version
supports GSS-Negotiate.
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 neces-
sarily 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)
NOTE that this option requiures that the library
was built with SSL support. Use curl --version to
see if your version 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
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.)
You may use this option as many times as you have
number of URLs.
-p/--proxytunnel
When an HTTP proxy is used, 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 num-
ber curl wants to tunnel through to.
If this option is used twice, the second will again
disable proxy tunnel.
-P/--ftpport <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 speci-
fied 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
used.
-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, by using the QUOTE command of the server.
Not all servers support this command, and the set
of QUOTE commands are server specific! Quote com-
mands are sent BEFORE the transfer is taking place.
To make commands take place after a successful
transfer, prefix them with a dash '-'. You may
specify any amount of commands to be run before and
after the transfer. If the server returns failure
for one of the commands, the entire operation will
be aborted.
This option can be used multiple times.
--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 --edg-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
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 dis-
ables this again.
-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.
--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.
-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.
This transfers the specified local file to the
remote URL. If there is no file part in the speci-
fied 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 direc-
tory 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.
If this option is used several times, the last one
will be used.
--trace <file>
Enables a full trace dump of all incoming and out-
going 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 out-
going 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 when fetching.
Read the MANUAL for detailed examples of how to use
this. If no password is specified, curl will ask
for it interactively.
You can also use the --digest option to enable
Digest authentication when communicating with HTTP
1.1 servers.
If this option is used several times, the last one
will be used.
Specify user and password to use for Proxy authen-
tication. If no password is specified, curl will
ask for it interactively.
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 or
the -O 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 additional info provided by curl.
Note that if you want to see 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 spe-
cific features libcurl reports to offer.
-w/--write-out <format>
Defines what to display after a completed and suc-
cessful operation. The format is a string that may
contain plain text mixed with any number of vari-
"@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 new-
line 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.
time_total The total time, in seconds, that the
full operation lasted. The time will
be displayed with millisecond reso-
lution.
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 com-
pleted.
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 nego-
tiations that are specific to the
particular protocol(s) involved.
time_starttransfer
The time, in seconds, it took from
the start until the first byte is
just about to be transfered. This
includes time_pretransfer and also
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. (Added
in 7.9.5)
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 vari-
ables that sets proxy to use. If there's an envi-
ronment variable setting a proxy, you can set proxy
to "" to override it.
Note that all operations that are performed over a
HTTP proxy will transparantly be converted to HTTP.
It means that certain protocol specific operations
might not be available. This is not the case if you
can tunnel through the proxy, as done with the
-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 com-
municating 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.
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 to get a file that has been modified
later than the given time and date, or one that has
been modified before that time. The date expression
can be all sorts of date strings or if it doesn't
match any internal ones, it tries to get the time
from a given file name instead! See the GNU date(1)
or 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.
-Z/--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.
(HTTPS) Forces curl to use SSL version 3 when nego-
tiating with a remote SSL server.
-2/--sslv2
(HTTPS) Forces curl to use SSL version 2 when nego-
tiating with a remote SSL server.
-0/--http1.0
(HTTP) Forces curl to issue its requests using HTTP
1.0 instead of using its internally preferred: HTTP
1.1.
-#/--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 messages 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
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 trans-
fered.
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.
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 --fail is used.
23 Write error. Curl couldn't write data to a local
filesystem or similar.
24 Malformat user. User name badly specified.
25 FTP couldn't STOR file. The server denied the STOR
operation.
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.
31 FTP couldn't use REST. The REST command failed.
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 ear-
lier 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
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
XX There will appear more error codes here in future
releases. The existing ones are meant to never
change.
BUGS
If you do find bugs, mail them to curl-bug@haxx.se.
AUTHORS / CONTRIBUTORS
WWW
http://curl.haxx.se
FTP
ftp://ftp.sunet.se/pub/www/utilities/curl/
SEE ALSO
ftp(1), wget(1), snarf(1)
Man(1) output converted with
man2html