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 (HTP, HTPS, FTP, FTPS, SCP,
SFTP, TFTP, 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, HTP post, SL connections,
cookies, file transfer resume and more. As you will see
below, the number 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 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 a 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
Curl 7.19.0 Last change: 10 July 2008 1
Curl Manual curl(1)
If you specify URL without protocol:/ prefix, curl will
attempt to guess what protocol you might want. It will then
default to HTP 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.
PROGRES METER
curl normally displays a progress meter during operations,
indicating the amount of transferred data, transfer speeds
and estimated time left, etc.
However, since curl displays this data to the terminal by
default, if you invoke curl to do an operation and it is
about to write data to the terminal, it disables the pro-
gress meter as otherwise it would mess up the output mixing
progress meter and response data.
If you want a progress meter for HTP POST or PUT requests,
you need to redirect the response output to a file, using
shell redirect (>), -o [file] or similar.
It is not the same case for FTP upload as that operation
does not spit out any response data to the terminal.
If you prefer a progress "bar" instead of the regular meter,
-# is your friend.
OPTIONS
In general, all boolean options are enabled with --option
and yet again disabled with --no-option. That is, you use
the exact same option name but prefix it with "no-". How-
ever, in this list we mostly only list and show the --option
version of them. (This concept with --no options was added
in 7.19.0. Previously most options were toggled on/off on
repeated use of the same command line option.)
-a/--append
(FTP/SFTP) When used in an 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. Note
that this flag is ignored by some SH servers (includ-
ing OpenSH).
-A/--user-agent
(HTP) Specify the User-Agent string to send to the
Curl 7.19.0 Last change: 10 July 2008 2
Curl Manual curl(1)
HTP server. Some badly done CGIs fail if this field
isn't 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
(HTP) Tells curl to figure out authentication method
by itself, and use the most secure one the remote site
claims to support. This is done by first doing a
request and checking the response-headers, thus possi-
bly 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.
-b/--cookie
(HTP) Pass the data to the HTP 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 '=' symbol 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
HTP headers or the Netscape/Mozilla cookie file for-
mat.
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 HTP 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
Curl 7.19.0 Last change: 10 July 2008 3
Curl Manual curl(1)
Enable ASCI 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.
--basic
(HTP) Tells curl to use HTP Basic authentication.
This is the default and this option is usually point-
less, unless you use it to override a previously set
option that sets a different authentication method
(such as --ntlm, --digest, or --negotiate).
--ciphers
(SL) Specifies which ciphers to use in the connection.
The list of ciphers must specify valid ciphers. Read up
on SL cipher list details on this URL:
http:/www.openssl.org/docs/apps/ciphers.html
NS ciphers are done differently than OpenSL and
GnuTLS. The full list of NS ciphers is in the NSCi-
pherSuite entry at this URL:
http:/directory.fedora.redhat.com/docs/modnss.html#Directives
If this option is used several times, the last one will
override the others.
--compressed
(HTP) 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.
--connect-timeout
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
Specify to which file you want curl to write all cook-
ies after a completed operation. Curl writes all cook-
ies previously read from a specified file as well as
all cookies received from remote server(s). If no cook-
ies 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 cook-
ies will be written to stdout.
Curl 7.19.0 Last change: 10 July 2008 4
Curl Manual curl(1)
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 speci-
fied file name will be used.
-C/--continue-at
Continue/Resume a previous file transfer at the given
offset. The given offset is the exact number of bytes
that will be skipped, counting from the beginning of
the source file before it is transferred to the desti-
nation. 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 or SFTP,
try --ftp-create-dirs.
--crlf
(FTP) Convert LF to CRLF in upload. Useful for MVS
(OS/390).
-d/--data
(HTP) Sends the specified data in a POST request to
the HTP server, in the same way that a browser does
when a user has filled in an HTML form and presses the
submit button. This will cause curl to pass the data to
the server using the content-type application/x-www-
form-urlencoded. Compare to -F/--form.
-d/--data is the same as --data-ascii. To post data
purely binary, you should instead use the --data-binary
option. To URL-encode the value of a form field you may
use --data-urlencode.
Curl 7.19.0 Last change: 10 July 2008 5
Curl Manual curl(1)
If any of these options is used more than once on the
same command line, the data pieces specified will be
merged together with a separating &-symbol. 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 con-
tents 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.
--data-binary
(HTP) This posts data exactly as specified with no
extra processing whatsoever.
If you start the data with the letter @, the rest
should be a filename. Data is posted in a similar
manner as --data-ascii does, except that newlines are
preserved and conversions are never done.
If this option is used several times, the ones follow-
ing the first will append data as described in -d/--
data.
--data-urlencode
(HTP) This posts data, similar to the other --data
options with the exception that this performs URL-
encoding. (Added in 7.18.0)
To be CGI-compliant, the part should begin with
a name followed by a separator and a content specifica-
tion. The part can be passed to curl using one
of the following syntaxes:
content
This will make curl URL-encode the content and
pass that on. Just be careful so that the content
doesn't contain any = or @ symbols, as that will
then make the syntax match one of the other cases
below!
=content
This will make curl URL-encode the content and
pass that on. The preceding = symbol is not
included in the data.
name=content
This will make curl URL-encode the content part
and pass that on. Note that the name part is
expected to be URL-encoded already.
Curl 7.19.0 Last change: 10 July 2008 6
Curl Manual curl(1)
@filename
This will make curl load data from the given file
(including any newlines), URL-encode that data and
pass it on in the POST.
name@filename
This will make curl load data from the given file
(including any newlines), URL-encode that data and
pass it on in the POST. The name part gets an
equal sign appended, resulting in
name=urlencoded-file-content. Note that the name
is expected to be URL-encoded already.
--digest
(HTP) Enables HTP Digest authentication. This is a
authentication that prevents the password from being
sent over the wire in clear text. Use this in combina-
tion with the normal -u/--user option to set user name
and password. See also --ntlm, --negotiate 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, and may not work on all servers,
but they enable more functionality in a better way than
the traditional PORT command.
Since curl 7.19.0, --eprt can be used to explicitly
enable EPRT again and --no-eprt is an alias for --
disable-eprt.
Disabling EPRT only changes the active behavior. If you
want to switch to passive mode you need to not use
-P/--ftp-port or force it with --ftp-pasv.
--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.
Since curl 7.19.0, --epsv can be used to explicitly
enable EPRT again and --no-epsv is an alias for --
disable-epsv.
Curl 7.19.0 Last change: 10 July 2008 7
Curl Manual curl(1)
Disabling EPSV only changes the passive behavior. If
you want to switch to active mode you need to use -P/-
-ftp-port.
-D/--dump-header
Write the protocol headers to the specified file.
This option is handy to use when you want to store the
headers that a HTP site sends to you. Cookies from the
headers could then be read in a second curl invocation
by using the -b/--cookie option! The -c/--cookie-jar
option is however a better way to store cookies.
When used in 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
(HTP) Sends the "Referer Page" information to the HTP
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
Select the OpenSL 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 allow easier
extraction of useful information after having run curl.
--egd-file
(SL) Specify the path name to the Entropy Gathering
Daemon socket. The socket is used to seed the random
engine for SL connections. See also the --random-file
option.
-E/--cert
(SL) Tells curl to use the specified certificate file
when getting a file with HTPS or FTPS. The certificate
must be in PEM format. If the optional password isn't
Curl 7.19.0 Last change: 10 July 2008 8
Curl Manual curl(1)
specified, it will be queried for on the terminal. Note
that this option assumes a "certificate" file that is
the private key and the private certificate con-
catenated! See --cert and --key to specify them
independently.
If curl is built against the NS SL library then this
option tells curl the nickname of the certificate to
use within the NS database defined by the environment
variable SLDIR (or by default /etc/pki/nssdb). If the
NS PEM PKCS#11 module (libnsspem.so) is available then
PEM files may be loaded.
If this option is used several times, the last one will
be used.
--cert-type
(SL) Tells curl what certificate type the provided
certificate is in. PEM, DER and ENG are recognized
types. If not specified, PEM is assumed.
If this option is used several times, the last one will
be used.
--cacert
(SL) 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.
Normally curl is built to use a default file for this,
so this option is typically used to alter that default
file.
curl recognizes the environment variable named
'CURLCABUNDLE' if it 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 Work-
ing Directory, or in any folder along your PATH.
If curl is built against the NS SL library then this
option tells curl the nickname of the CA certificate to
use within the NS database defined by the environment
variable SLDIR (or by default /etc/pki/nssdb). If
the NS PEM PKCS#11 module (libnsspem.so) is available
then PEM files may be loaded.
If this option is used several times, the last one will
be used.
Curl 7.19.0 Last change: 10 July 2008 9
Curl Manual curl(1)
--capath
(SL) 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 pro-
cessed using the crehash utility supplied with
openssl. Using --capath can allow curl to make SL-
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
(HTP) Fail silently (no output at all) on server
errors. This is mostly done to better enable scripts
etc to better deal with failed attempts. In normal
cases when a HTP 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.
This method is not fail-safe and there are occasions
where non-successful response codes will slip through,
especially when authentication is involved (response
codes 401 and 407).
--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 ACT command. (Added in 7.13.0)
If this option is used twice, the second will override
the previous use.
--ftp-create-dirs
(FTP/SFTP) When an FTP or SFTP 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.
--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.
Curl 7.19.0 Last change: 10 July 2008 10
Curl Manual curl(1)
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 stan-
dards compliant than 'nocwd' but without the full
penalty of 'multicwd'.
(Added in 7.15.1)
--ftp-pasv
(FTP) Use passive mode for the data conection. Passive
is the internal default behavior, but using this option
can be used to override a previous -P/-ftp-port option.
(Added in 7.11.0)
If this option is used several times, the following
occurrences make no difference. Undoing an enforced
passive really isn't doable but you must then instead
enforce the correct -P/--ftp-port again.
Passive mode means that curl will try the EPSV command
first and then PASV, unless --disable-epsv is used.
--ftp-alternative-to-user
(FTP) If authenticating with the USER and PAS 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 con-
trol connection. (Added in 7.14.2)
This option has no effect if PORT, EPRT or EPSV is used
instead of PASV.
--ftp-ssl
(FTP) Try to use SL/TLS for the FTP connection.
Reverts to a non-secure connection if the server
doesn't support SL/TLS. See also --ftp-ssl-control
and --ftp-ssl-reqd for different levels of encryption
required. (Added in 7.11.0)
Curl 7.19.0 Last change: 10 July 2008 11
Curl Manual curl(1)
--ftp-ssl-control
(FTP) Require SL/TLS for the FTP login, clear for
transfer. Allows secure authentication, but non-
encrypted data transfers for efficiency. Fails the
transfer if the server doesn't support SL/TLS. (Added
in 7.16.0)
--ftp-ssl-reqd
(FTP) Require SL/TLS for the FTP connection. Ter-
minates the connection if the server doesn't support
SL/TLS. (Added in 7.15.5)
--ftp-ssl-ccc
(FTP) Use C (Clear Command Channel) Shuts down the
SL/TLS layer after authenticating. The rest of the
control channel communication will be unencrypted. This
allows NAT routers to follow the FTP transaction. The
default mode is passive. See --ftp-ssl-ccc-mode for
other modes. (Added in 7.16.1)
--ftp-ssl-ccc-mode [active/passive]
(FTP) Use C (Clear Command Channel) Sets the C
mode. The passive mode will not initiate the shutdown,
but instead wait for the server to do it, and will not
reply to the shutdown from the server. The active mode
initiates the shutdown and waits for a reply from the
server. (Added in 7.16.2)
-F/--form
(HTP) 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
symbol <. 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 con-
tents 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
Curl 7.19.0 Last change: 10 July 2008 12
Curl Manual curl(1)
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
(HTP) 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 HTP
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. This is because undoing
a GET doesn't make sense, but you should then instead
enforce the alternative method you prefer.
-h/--help
Usage help.
Curl 7.19.0 Last change: 10 July 2008 13
Curl Manual curl(1)
-H/--header
(HTP) 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 exter-
nally 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 inter-
nally set headers without knowing perfectly well what
you're doing. Remove an internal header by giving a
replacement without content on the right side of the
colon, as in: -H "Host:".
curl will make sure that each header you add/replace is
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.
--hostpubmd5
Pass a string containing 32 hexadecimal digits. The
string should be the 128 bit MD5 checksum of the remote
host's public key, curl will refuse the connection with
the host unless the md5sums match. This option is only
for SCP and SFTP transfers. (Added in 7.17.1)
--ignore-content-length
(HTP) Ignore the Content-Length header. This is par-
ticularly useful for servers running Apache 1.x, which
will report incorrect Content-Length for files larger
than 2 gigabytes.
-i/--include
(HTP) Include the HTP-header in the output. The
HTP-header includes things like server-name, date of
the document, HTP-version and more...
--interface
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.
Curl 7.19.0 Last change: 10 July 2008 14
Curl Manual curl(1)
-I/--head
(HTP/FTP/FILE) Fetch the HTP-header only! HTP-
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.
-j/--junk-session-cookies
(HTP) 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.
-k/--insecure
(SL) This option explicitly allows curl to perform
"insecure" SL connections and transfers. All SL con-
nections are attempted to be made secure by using the
CA certificate bundle installed by default. This makes
all connections considered "insecure" fail unless -k/-
-insecure is used.
See this online resource for further details:
http:/curl.haxx.se/docs/sslcerts.html
--keepalive-time
This option sets the time a connection needs to remain
idle before sending keepalive probes and the time
between individual keepalive probes. It is currently
effective on operating systems offering the
TCPKEPIDLE and TCPKEPINTVL socket options (meaning
Linux, recent AIX, HP-UX and more). This option has no
effect if --no-keepalive is used. (Added in 7.18.0)
If this option is used multiple times, the last
occurrence sets the amount.
--key
(SL/SH) 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
(SL) Private key file type. Specify which type your
--key provided private key is. DER, PEM, and ENG are
supported. If not specified, PEM is assumed.
If this option is used several times, the last one will
be used.
Curl 7.19.0 Last change: 10 July 2008 15
Curl Manual curl(1)
--krb
(FTP) Enable Kerberos 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 a library built with kerberos4 or
GSAPI (GS-Negotiate) support. This is not very com-
mon. 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
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 con-
fig file line, separated by whitespace, colon, the
equals sign or any combination thereof (however, the
preferred separator is the equals sign). If the parame-
ter is to contain whitespace, the parameter must be
enclosed within quotes. Within double quotes, the fol-
lowing escape sequences are available: \\, \", \t, \n,
\r and \v. A backslash preceding any other letter is
ignored. If the first column of a config line is a '#'
character, the rest of the line will be treated as a
comment. Only write one option per physical line in the
config file.
Specify the filename to -K/--config 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/"
Long option names can optionally be given in the config
file without the initial double dashes.
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 CURLHOME and then the HOME environment
Curl 7.19.0 Last change: 10 July 2008 16
Curl Manual curl(1)
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 APDATA variable, or as a last resort
the '%USERPROFILE%\Application Data'.
2) On windows, if there is no curlrc file in the home
dir, it checks for one in the same dir the curl execut-
able is placed. On UNIX-like systems, it will simply
try to load .curlrc from the determined home dir.
# --- Example file ---
# this is a comment
url = "curl.haxx.se"
output = "curlhere.html"
user-agent = "superagent/1.0"
# and fetch another URL too
url = "curl.haxx.se/docs/manpage.html"
-O
referer = "http:/nowhereatall.com/"
# --- End of example file ---
This option can be used multiple times to load multiple
config files.
--libcurl
Append this option to any ordinary curl command line,
and you will get a libcurl-using source code written to
the file that does the equivalent of what your
command-line operation does!
NOTE: this does not properly support -F and the sending
of multipart formposts, so in those cases the output
program will be missing necessary calls to
curlformadd(3), and possibly more.
If this option is used several times, the last given
file name will be used. (Added in 7.16.1)
--limit-rate
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 to 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.
Curl 7.19.0 Last change: 10 July 2008 17
Curl Manual curl(1)
The given rate is the average speed counted during the
entire transfer. It means that curl might use higher
transfer speeds in short bursts, but over time it uses
no more than the given rate.
If you also use 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.
--local-port [-num]
Set a preferred number or range of local port numbers
to use for the connection(s). Note that port numbers
by nature are 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
(HTP/HTPS) If the server reports that the requested
page has moved to a different location (indicated with
a Location: header and a 3X 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 dif-
ferent 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.
When curl follows a redirect and the request is not a
plain GET (for example POST or PUT), it will do the
following request with a GET if the HTP response was
301, 302, or 303. If the response code was any other
Curl 7.19.0 Last change: 10 July 2008 18
Curl Manual curl(1)
3xx code, curl will re-send the following request using
the same unmodified method.
--location-trusted
(HTP/HTPS) 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 to a site to which
you'll send your authentication info (which is plain-
text in the case of HTP Basic authentication).
--max-filesize
Specify the maximum size (in bytes) of a file to down-
load. 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 down-
load, 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 HTP transfers.
-m/--max-time
Maximum time in seconds that you allow the whole opera-
tion 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.
-M/--manual
Manual. Display the huge help text.
-n/--netrc
Makes curl scan the .netrc (netrc on Windows) file in
the user's home directory for login name and password.
This is typically used for FTP on UNIX. If used with
HTP, curl will enable user authentication. See
netrc(4) or ftp(1) for details on the file format. Curl
will not complain if that file doesn't have the right
permissions (it should not be either world- or 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:
Curl 7.19.0 Last change: 10 July 2008 19
Curl Manual curl(1)
machine host.domain.com login myself password secret
--netrc-optional
Very similar to --netrc, but this option makes the
.netrc usage optional and not mandatory as the --netrc
option does.
--negotiate
(HTP) Enables GS-Negotiate authentication. The GS-
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 method. For more
information see IETF draft draft-brezak-spnego-http-
04.txt.
If you want to enable Negotiate for your proxy authen-
tication, then use --proxy-negotiate.
This option requires a library built with GSAPI sup-
port. This is not very common. Use -V/--version to see
if your version supports GS-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 out-
put stream that will have the effect that it will out-
put the data in chunks, not necessarily exactly when
the data arrives. Using this option will disable that
buffering.
Note that this is the negated option name documented.
You can thus use --buffer to enforce the buffering.
--no-keepalive
Disables the use of keepalive messages on the TCP con-
nection, as by default curl enables them.
Note that this is the negated option name documented.
You can thus use --keepalive to enforce keepalive.
--no-sessionid
(SL) Disable curl's use of SL session-ID caching. By
default all transfers are done using the cache. Note
Curl 7.19.0 Last change: 10 July 2008 20
Curl Manual curl(1)
that while nothing should ever get hurt by attempting
to reuse SL session-IDs, there seem to be broken SL
implementations in the wild that may require you to
disable this in order for you to succeed. (Added in
7.16.0)
Note that this is the negated option name documented.
You can thus use --sessionid to enforce session-ID
caching.
--noproxy
Comma-separated list of hosts which do not use a proxy,
if one is specified. The only wildcard is a single *
character, which matches all hosts, and effectively
disables the proxy. Each name in this list is matched
as either a domain which contains the hostname, or the
hostname itself. For example, local.com would match
local.com, local.com:80, and www.local.com, but not
www.notlocal.com. (Added in 7.19.4).
--ntlm
(HTP) Enables NTLM authentication. The NTLM authenti-
cation method was designed by Microsoft and is used by
IS web servers. It is a proprietary protocol,
reverse-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 authentica-
tion, then use --proxy-ntlm.
This option requires a library built with SL 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
Write output to instead of stdout. If you are
using {} or [] to fetch multiple documents, you can use
'#' followed by a number in the 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"
Curl 7.19.0 Last change: 10 July 2008 21
Curl Manual curl(1)
You may use this option as many times as the number of
URLs you have.
See also the --create-dirs option to create the local
directories dynamically. Specifying the output as '-'
(a single dash) will force the output to be done to
stdout.
-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 the number of
URLs you have.
--remote-name-all
This option changes the default action for all given
URLs to be dealt with as if -O/--remote-name were used
for each one. So if you want to disable that for a
specific URL after --remote-name-all has been used, you
must use "-o -" or --no-remote-name. (Added in 7.19.0)
--pass
(SL/SH) Passphrase for the private key
If this option is used several times, the last one will
be used.
--post301
Tells curl to respect RFC 2616/10.3.2 and not convert
POST requests into GET requests when following a 301
redirection. The non-RFC behaviour is ubiquitous in web
browsers, so curl does the conversion by default to
maintain consistency. However, a server may require a
POST to remain a POST after such a redirection. This
option is meaningful only when using -L/--location
(Added in 7.17.1)
--post302
Tells curl to respect RFC 2616/10.3.2 and not convert
POST requests into GET requests when following a 302
redirection. The non-RFC behaviour is ubiquitous in web
browsers, so curl does the conversion by default to
maintain consistency. However, a server may require a
POST to remain a POST after such a redirection. This
option is meaningful only when using -L/--location
(Added in 7.19.1)
Curl 7.19.0 Last change: 10 July 2008 22
Curl Manual curl(1)
--proxy-anyauth
Tells curl to pick a suitable authentication method
when communicating with the given proxy. This might
cause an extra request/response round-trip. (Added in
7.13.2)
--proxy-basic
Tells curl to use HTP Basic authentication when com-
municating with the given proxy. Use --basic for ena-
bling HTP Basic with a remote host. Basic is the
default authentication method curl uses with proxies.
--proxy-digest
Tells curl to use HTP Digest authentication when com-
municating with the given proxy. Use --digest for ena-
bling HTP Digest with a remote host.
--proxy-negotiate
Tells curl to use HTP Negotiate authentication when
communicating with the given proxy. Use --negotiate for
enabling HTP Negotiate with a remote host. (Added in
7.17.1)
--proxy-ntlm
Tells curl to use HTP NTLM authentication when commun-
icating with the given proxy. Use --ntlm for enabling
NTLM with a remote host.
--proxy1.0
Use the specified HTP 1.0 proxy. If the port number is
not specified, it is assumed at port 1080.
The only difference between this and the HTP proxy
option (-x/--proxy), is that attempts to use CONECT
through the proxy will specify an HTP 1.0 protocol
instead of the default HTP 1.1.
-p/--proxytunnel
When an HTP proxy is used (-x/--proxy), this option
will cause non-HTP protocols to attempt to tunnel
through the proxy instead of merely using it to do
HTP-like operations. The tunnel approach is made with
the HTP proxy CONECT request and requires that the
proxy allows direct connect to the remote port number
curl wants to tunnel through to.
--pubkey
(SH) Public key file name. Allows you to provide your
public key in this separate file.
If this option is used several times, the last one will
be used.
Curl 7.19.0 Last change: 10 July 2008 23
Curl Manual curl(1)
-P/--ftp-port
(FTP) Reverses the default initiator/listener roles
when connecting with FTP. This switch makes curl use
active mode. In practice, curl then tells the server to
connect back to the client's specified address and
port, while passive mode asks the server to setup an IP
address and port for it to connect to. 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 the exact IP address
host name
i.e "my.host.domain" to specify the 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
(FTP/SFTP) Send an arbitrary command to the remote FTP
or SFTP server. Quote commands are sent BEFORE the
transfer takes place (just after the initial PWD com-
mand in an FTP transfer, to be exact). To make commands
take place after a successful transfer, prefix them
with a dash '-'. To make commands be sent after lib-
curl has changed the working directory, just before the
transfer command(s), prefix the command with a ']'
(this is only supported for FTP). You may specify any
number of commands. If the server returns failure for
one of the commands, the entire operation will be
aborted. You must send syntactically correct FTP com-
mands as RFC959 defines to FTP servers, or one of the
commands listed below to SFTP servers. This option can
be used multiple times.
SFTP is a binary protocol. Unlike for FTP, libcurl
interprets SFTP quote commands before sending them to
the server. Following is the list of all supported
Curl 7.19.0 Last change: 10 July 2008 24
Curl Manual curl(1)
SFTP quote commands:
chgrp group file
The chgrp command sets the group ID of the file
named by the file operand to the group ID speci-
fied by the group operand. The group operand is a
decimal integer group ID.
chmod mode file
The chmod command modifies the file mode bits of
the specified file. The mode operand is an octal
integer mode number.
chown user file
The chown command sets the owner of the file named
by the file operand to the user ID specified by
the user operand. The user operand is a decimal
integer user ID.
ln sourcefile targetfile
The ln and symlink commands create a symbolic link
at the targetfile location pointing to the
sourcefile location.
mkdir directoryname
The mkdir command creates the directory named by
the directoryname operand.
pwd The pwd command returns the absolute pathname of
the current working directory.
rename source target
The rename command renames the file or directory
named by the source operand to the destination
path named by the target operand.
rm file
The rm command removes the file specified by the
file operand.
rmdir directory
The rmdir command removes the directory entry
specified by the directory operand, provided it is
empty.
symlink sourcefile targetfile
See ln.
--random-file
(SL) Specify the path name to file containing what
will be considered as random data. The data is used to
seed the random engine for SL connections. See also
Curl 7.19.0 Last change: 10 July 2008 25
Curl Manual curl(1)
the --egd-file option.
-r/--range
(HTP/FTP/SFTP/FILE) Retrieve a byte range (i.e a par-
tial document) from a HTP/1.1, FTP or SFTP server or a
local FILE. 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 for-
ward
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-byte ranges(*)(H)
(*) = NOTE that this will cause the server to reply with a
multipart response!
Only digit characters (0-9) are valid in the 'start' and
'stop' fields of the 'start-stop' range syntax. If a non-
digit character is given in the range, the server's response
will be unspecified, depending on the server's configura-
tion.
You should also be aware that many HTP/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 and SFTP range downloads only support the simple
'start-stop' syntax (optionally with one of the numbers
omitted). FTP use depends on the extended FTP command SIZE.
If this option is used several times, the last one will be
used.
--raw
When used, it disables all internal HTP decoding of
content or transfer encodings and instead makes them
passed on unaltered, raw. (Added in 7.16.2)
-R/--remote-time
When used, this will make libcurl attempt to figure out
Curl 7.19.0 Last change: 10 July 2008 26
Curl Manual curl(1)
the timestamp of the remote file, and if that is avail-
able make the local file get that same timestamp.
--retry
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 HTP 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
Make curl sleep this amount of time before 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 determines the amount.
--retry-max-time
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. (Added in
7.12.3)
If this option is used multiple times, the last
occurrence determines the amount.
-s/--silent
Silent mode. Don't show progress meter or error mes-
sages. Makes Curl mute.
Curl 7.19.0 Last change: 10 July 2008 27
Curl Manual curl(1)
-S/--show-error
When used with -s it makes curl show an error message
if it fails.
--socks4
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.
--socks4a
Use the specified SOCKS4a proxy. If the port number is
not specified, it is assumed at port 1080. (Added in
7.18.0)
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-hostname
Use the specified SOCKS5 proxy (and let the proxy
resolve the host name). If the port number is not
specified, it is assumed at port 1080. (Added in
7.18.0)
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.)
--socks5
Use the specified SOCKS5 proxy - but resolve the host
name locally. If the port number is not specified, it
is assumed at port 1080.
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.)
--socks5-gssapi-service
Curl 7.19.0 Last change: 10 July 2008 28
Curl Manual curl(1)
The default service name for a socks server is
rcmd/server-fqdn. This option allows you to change it.
Examples:
--socks5 proxy-name --socks5-gssapi-service sockd
would use sockd/proxy-name
--socks5 proxy-name --socks5-gssapi-service
sockd/real-name would use sockd/real-name for cases
where the proxy-name does not match the princpal name.
(Added in 7.19.4).
--socks5-gssapi-nec
As part of the gssapi negotiation a protection mode is
negotiated. The rfc1961 says in section 4.3/4.4 it
should be protected, but the NEC reference implementa-
tion does not. The option --socks5-gssapi-nec allows
the unprotected exchange of the protection mode nego-
tiation. (Added in 7.19.4).
--stderr
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 TCPNODELAY option. See the
curleasysetopt(3) man page for details about this
option. (Added in 7.11.2)
-t/--telnet-option
Pass options to the telnet protocol. Supported options
are:
TYPE= Sets the terminal type.
XDISPLOC= Sets the X display location.
NEWENV= Sets an environment variable.
-T/--upload-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 HTP(S) server,
Curl 7.19.0 Last change: 10 July 2008 29
Curl Manual curl(1)
the PUT command will be used.
Use the file name "-" (a single dash) to use stdin
instead of a given file.
You can specify one -T for each URL on the command
line. Each -T ] URL pair specifies what to upload and
to where. curl also supports "globbing" of the -T argu-
ment, meaning that you can upload multiple files to a
single URL by using the same URL globbing style sup-
ported 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
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 option overrides previous uses of -v/--verbose or
--trace-ascii.
If this option is used several times, the last one will
be used.
--trace-ascii
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 ASCI part of the dump. It
makes smaller output that might be easier to read for
untrained humans.
This option overrides previous uses of -v/--verbose or
--trace.
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)
Curl 7.19.0 Last change: 10 July 2008 30
Curl Manual curl(1)
-u/--user
Specify the user name and password to use for server
authentication. Overrides -n/--netrc and --netrc-
optional.
If you just give the user name (without entering a
colon) curl will prompt for a password.
If you use an SPI-enabled curl binary and do NTLM
authentication, 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
Specify the user name and password to use for proxy
authentication.
If you use an SPI-enabled curl binary and do NTLM
authentication, 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
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 use-
ful for debugging. A line starting with '>' means
"header data" sent by curl, '<' means "header data"
received by curl that is hidden in normal cases, and a
line starting with '*' means additional info provided
by curl.
Note that if you only want HTP headers in the output,
-i/--include might be the option you're looking for.
If you think this option still doesn't give you enough
details, consider using --trace or --trace-ascii
instead.
This option overrides previous uses of --trace-ascii or
Curl 7.19.0 Last change: 10 July 2008 31
Curl Manual curl(1)
--trace.
-V/--version
Displays information about curl and the libcurl version
it uses.
The first line includes the full version of curl, lib-
curl and other 3rd party libraries linked with the exe-
cutable.
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.
SL HTPS and FTPS are supported.
libz Automatic decompression of compressed files over
HTP is supported.
NTLM NTLM authentication is supported.
GS-Negotiate
Negotiate authentication and krb5 for FTP is sup-
ported.
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.
SPI SPI is supported. If you use NTLM and set a blank
user name, curl will authenticate with your
Curl 7.19.0 Last change: 10 July 2008 32
Curl Manual curl(1)
current user and password.
-w/--write-out
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 sub-
stituted by the value or text that curl thinks fit, as
described below. All variables are specified as
%{variablename} and to output a normal % you just
write them as %%. You can output a newline by using \n,
a carriage return with \r and a tab space with \t.
NOTE: The %-symbol is a special symbol in the win32-
environment, where all occurrences of % must be doubled
when using this option.
The variables available at this point are:
urleffective The URL that was fetched last. This is
most meaningful if you've told curl to
follow location: headers.
httpcode The numerical response code that was
found in the last retrieved HTP(S) or
FTP(s) transfer. In 7.18.2 the alias
responsecode was added to show the same
info.
httpconnect The numerical code that was found in the
last response (from a proxy) to a curl
CONECT request. (Added in 7.12.4)
timetotal The total time, in seconds, that the
full operation lasted. The time will be
displayed with millisecond resolution.
timenamelookup
The time, in seconds, it took from the
start until the name resolving was com-
pleted.
timeconnect The time, in seconds, it took from the
start until the TCP connect to the
remote host (or proxy) was completed.
timeappconnect
Curl 7.19.0 Last change: 10 July 2008 33
Curl Manual curl(1)
The time, in seconds, it took from the
start until the SL/SH/etc
connect/handshake to the remote host was
completed. (Added in 7.19.0)
timepretransfer
The time, in seconds, it took from the
start until the file transfer was just
about to begin. This includes all pre-
transfer commands and negotiations that
are specific to the particular
protocol(s) involved.
timeredirect The time, in seconds, it took for all
redirection steps include name lookup,
connect, pretransfer and transfer before
the final transaction was started.
timeredirect shows the complete execu-
tion time for multiple redirections.
(Added in 7.12.3)
timestarttransfer
The time, in seconds, it took from the
start until the first byte was just
about to be transferred. This includes
timepretransfer and also the time the
server needed to calculate the result.
sizedownload The total amount of bytes that were
downloaded.
sizeupload The total amount of bytes that were
uploaded.
sizeheader The total amount of bytes of the down-
loaded headers.
sizerequest The total amount of bytes that were sent
in the HTP request.
speeddownload The average download speed that curl
measured for the complete download.
speedupload The average upload speed that curl meas-
ured for the complete upload.
contenttype The Content-Type of the requested docu-
ment, if there was any.
numconnects Number of new connects made in the
recent transfer. (Added in 7.12.3)
Curl 7.19.0 Last change: 10 July 2008 34
Curl Manual curl(1)
numredirects Number of redirects that were followed
in the request. (Added in 7.12.3)
redirecturl When a HTP request was made without -L
to follow redirects, this variable will
show the actual URL a redirect would
take you to. (Added in 7.18.2)
ftpentrypath The initial path libcurl ended up in
when logging on to the remote FTP
server. (Added in 7.15.4)
sslverifyresult
The result of the SL peer certificate
verification that was requested. 0 means
the verification was successful. (Added
in 7.19.0)
If this option is used several times, the last one will be
used.
-x/--proxy
Use the specified HTP proxy. If the port number is not
specified, it is assumed at port 1080.
This option overrides existing environment variables
that set the 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 HTP
proxy will transparently be converted to HTP. 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,
including the protocol prefix (http:/) and the embed-
ded user ] password.
If this option is used several times, the last one will
be used.
-X/--request
(HTP) Specifies a custom request method to use when
communicating with the HTP server. The specified
request will be used instead of the method otherwise
used (which defaults to GET). Read the HTP 1.1 specif-
ication for details and explanations.
Curl 7.19.0 Last change: 10 July 2008 35
Curl Manual curl(1)
(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
