File: //proc/self/root/proc/self/root/usr/share/man/ecure
curl(1) Curl Manual curl(1)
NNAAMMEE
curl - transfer a URL
SSYYNNOOPPSSIISS
ccuurrll [[ooppttiioonnss]] _[_U_R_L_._._._]
DDEESSCCRRIIPPTTIIOONN
ccuurrll is a tool to transfer data from or to a server, using one of the supported protocols (HTTP, HTTPS, FTP, FTPS, SCP, SFTP, TFTP, DICT, TEL-
NET, 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 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 lliibbccuurrll(3) for details.
UURRLL
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
If you specify URL without protocol:// prefix, curl will attempt to guess what protocol you might want. It will then default to HTTP but try
other protocols based on often-used host name prefixes. For example, for host names starting with "ftp." curl will assume you want to speak FTP.
curl will do its best to use what you pass to it as a URL. It is not trying to validate it as a syntactically correct URL by any means but is
instead vveerryy liberal with what it accepts.
Curl will attempt to re-use connections for multiple file transfers, so that getting many files from the same server will not do multiple con-
nects / handshakes. This improves speed. Of course this is only done on files specified on a single command line and cannot be used between sep-
arate curl invokes.
PPRROOGGRREESSSS MMEETTEERR
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 _d_i_s_a_b_l_e_s the progress meter as otherwise it would mess up the output mixing progress meter and response data.
If you want a progress meter for HTTP 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.
OOPPTTIIOONNSS
In general, all boolean options are enabled with --option and yet again disabled with --nnoo--option. That is, you use the exact same option name
but prefix it with "no-". However, 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 SSH servers (including OpenSSH).
-A/--user-agent <agent string>
(HTTP) Specify the User-Agent string to send to the HTTP 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_/_-_-_h_e_a_d_e_r option of course.
If this option is set more than once, the last one will be the one that’s used.
--anyauth
(HTTP) Tells curl to figure out authentication method by itself, and use the most secure one the remote site claims to support. This is
done by first doing a request and checking the response-headers, thus possibly inducing an extra network round-trip. This is used instead
of setting a specific authentication method, which you can do with _-_-_b_a_s_i_c, _-_-_d_i_g_e_s_t, _-_-_n_t_l_m, and _-_-_n_e_g_o_t_i_a_t_e.
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 <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 ’=’ 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_/_-_-_l_o_c_a_t_i_o_n option. The file format of the file to read cookies
from should be plain HTTP headers or the Netscape/Mozilla cookie file format.
NNOOTTEE that the file specified with _-_b_/_-_-_c_o_o_k_i_e is only used as input. No cookies will be stored in the file. To store cookies, use the
_-_c_/_-_-_c_o_o_k_i_e_-_j_a_r option or you could even save the HTTP headers to a file using _-_D_/_-_-_d_u_m_p_-_h_e_a_d_e_r!
If this option is set more than once, the last one will be the one that’s used.
-B/--use-ascii
Enable ASCII transfer when using FTP or LDAP. For FTP, this can also be enforced by using an URL that ends with ";type=A". This option
causes data sent to stdout to be in text mode for win32 systems.
--basic
(HTTP) Tells curl to use HTTP Basic authentication. This is the default and this option is usually pointless, unless you use it to over-
ride a previously set option that sets a different authentication method (such as _-_-_n_t_l_m, _-_-_d_i_g_e_s_t, or _-_-_n_e_g_o_t_i_a_t_e).
--ciphers <list of ciphers>
(SSL) Specifies which ciphers to use in the connection. The list of ciphers must specify valid ciphers. Read up on SSL cipher list
details on this URL: _h_t_t_p_:_/_/_w_w_w_._o_p_e_n_s_s_l_._o_r_g_/_d_o_c_s_/_a_p_p_s_/_c_i_p_h_e_r_s_._h_t_m_l
NSS ciphers are done differently than OpenSSL and GnuTLS. The full list of NSS ciphers is in the NSSCipherSuite entry at this URL:
_h_t_t_p_:_/_/_d_i_r_e_c_t_o_r_y_._f_e_d_o_r_a_._r_e_d_h_a_t_._c_o_m_/_d_o_c_s_/_m_o_d___n_s_s_._h_t_m_l_#_D_i_r_e_c_t_i_v_e_s
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.
--connect-timeout <seconds>
Maximum time in seconds that you allow the connection to the server to take. This only limits the connection phase, once curl has con-
nected this option is of no more use. See also the _-_m_/_-_-_m_a_x_-_t_i_m_e option.
If this option is used several times, the last one will be used.
-c/--cookie-jar <file name>
Specify to which file you want curl to write all cookies after a completed operation. Curl writes all cookies previously read from a
specified file as well as all cookies received from remote server(s). If no cookies are known, no file will be written. The file will be
written using the Netscape cookie file format. If you set the file name to a single dash, "-", the cookies will be written to stdout.
NNOOTTEE If the cookie jar can’t be created or written to, the whole curl operation won’t fail or even report an error clearly. Using -v will
get a warning displayed, but that is the only visible feedback you get about this possibly lethal situation.
If this option is used several times, the last specified file name will be used.
-C/--continue-at <offset>
Continue/Resume a previous file transfer at the given offset. The given offset is the exact number of bytes that will be skipped, count-
ing from the beginning of the source file before it is transferred to the destination. If used with uploads, the FTP server command SIZE
will not be used by curl.
Use "-C -" to tell curl to automatically find out where/how to resume the transfer. It then uses the given output/input files to figure
that out.
If this option is used several times, the last one will be used.
--create-dirs
When used in conjunction with the -o option, curl will create the necessary local directory hierarchy as needed. This option creates the
dirs mentioned with the -o option, nothing else. If the -o file name uses no dir or if the dirs it mentions already exist, no dir will be
created.
To create remote directories when using FTP or SFTP, try _-_-_f_t_p_-_c_r_e_a_t_e_-_d_i_r_s.
--crlf (FTP) Convert LF to CRLF in upload. Useful for MVS (OS/390).
--crlfile <file>
(HTTPS/FTPS) Provide a file using PEM format with a Certificate Revocation List that may specify peer certificates that are to be consid-
ered revoked.
If this option is used several times, the last one will be used.
(Added in 7.19.7)
-d/--data <data>
(HTTP) Sends the specified data in a POST request to the HTTP 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_/_-_-_f_o_r_m.
_-_d_/_-_-_d_a_t_a is the same as _-_-_d_a_t_a_-_a_s_c_i_i. To post data purely binary, you should instead use the _-_-_d_a_t_a_-_b_i_n_a_r_y option. To URL-encode the
value of a form field you may use _-_-_d_a_t_a_-_u_r_l_e_n_c_o_d_e.
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 sepa-
rating &-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 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 _-_-_d_a_t_a _@_f_o_o_b_a_r.
--data-binary <data>
(HTTP) 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 _-_-_d_a_t_a_-_a_s_c_i_i does, except
that newlines are preserved and conversions are never done.
If this option is used several times, the ones following the first will append data as described in _-_d_/_-_-_d_a_t_a.
--data-urlencode <data>
(HTTP) 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 <data> part should begin with a _n_a_m_e followed by a separator and a content specification. The <data> 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 @ sym-
bols, 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.
@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 _n_a_m_e_=_u_r_l_e_n_c_o_d_e_d_-_f_i_l_e_-_c_o_n_t_e_n_t. Note that the name is expected to be URL-encoded
already.
--delegation LEVEL
Set _L_E_V_E_L to tell the server what it is allowed to delegate when it comes to user credentials. Used with GSS/kerberos.
none Don’t allow any delegation.
policy Delegates if and only if the OK-AS-DELEGATE flag is set in the Kerberos service ticket, which is a matter of realm policy.
always Unconditionally allow the server to delegate.
--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_/_-_-_u_s_e_r option to set user name and password. See also _-_-_n_t_l_m, _-_-_n_e_g_o_t_i_a_t_e and _-_-_a_n_y_a_u_t_h
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, ----eepprrtt can be used to explicitly enable EPRT again and ----nnoo--eepprrtt is an alias for ----ddiissaabbllee--eepprrtt.
Disabling EPRT only changes the active behavior. If you want to switch to passive mode you need to not use _-_P_/_-_-_f_t_p_-_p_o_r_t or force it with
_-_-_f_t_p_-_p_a_s_v.
--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, ----eeppssvv can be used to explicitly enable EPRT again and ----nnoo--eeppssvv is an alias for ----ddiissaabbllee--eeppssvv.
Disabling EPSV only changes the passive behavior. If you want to switch to active mode you need to use _-_P_/_-_-_f_t_p_-_p_o_r_t.
-D/--dump-header <file>
Write the protocol headers to the specified file.
This option is handy to use when you want to store the headers that a HTTP site sends to you. Cookies from the headers could then be read
in a second curl invocation by using the _-_b_/_-_-_c_o_o_k_i_e option! The _-_c_/_-_-_c_o_o_k_i_e_-_j_a_r 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 <URL>
(HTTP) Sends the "Referer Page" information to the HTTP server. This can also be set with the _-_H_/_-_-_h_e_a_d_e_r flag of course. When used with
_-_L_/_-_-_l_o_c_a_t_i_o_n you can append ";auto" to the --referer URL to make curl automatically set the previous URL when it follows a Location:
header. The ";auto" string can be used alone, even if you don’t set an initial --referer.
If this option is used several times, the last one will be used.
--engine <name>
Select the OpenSSL crypto engine to use for cipher operations. Use _-_-_e_n_g_i_n_e _l_i_s_t 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 infor-
mation after having run curl.
--egd-file <file>
(SSL) Specify the path name to the Entropy Gathering Daemon socket. The socket is used to seed the random engine for SSL connections. See
also the _-_-_r_a_n_d_o_m_-_f_i_l_e option.
-E/--cert <certificate[:password]>
(SSL) Tells curl to use the specified certificate file when getting a file with HTTPS or FTPS. The certificate must be in PEM format. If
the optional password isn’t specified, it will be queried for on the terminal. Note that this option assumes a "certificate" file that is
the private key and the private certificate concatenated! See _-_-_c_e_r_t and _-_-_k_e_y to specify them independently.
If curl is built against the NSS SSL library then this option can tell curl the nickname of the certificate to use within the NSS
database defined by the environment variable SSL_DIR (or by default /etc/pki/nssdb). If the NSS PEM PKCS#11 module (libnsspem.so) is
available then PEM files may be loaded. If you want to use a file from the current directory, please precede it with "./" prefix, in
order to avoid confusion with a nickname.
If this option is used several times, the last one will be used.
--cert-type <type>
(SSL) Tells curl what certificate type the provided certificate is in. PEM, DER and ENG are recognized types. If not specified, PEM is
assumed.
If this option is used several times, the last one will be used.
--cacert <CA certificate>
(SSL) Tells curl to use the specified certificate file to verify the peer. The file may contain multiple CA certificates. The certifi-
cate(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 ’CURL_CA_BUNDLE’ 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 Working Directory, or in any folder along your PATH.
If curl is built against the NSS SSL library then this option tells curl the nickname of the CA certificate to use within the NSS
database defined by the environment variable SSL_DIR (or by default /etc/pki/nssdb). If the NSS 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.
--capath <CA certificate directory>
(SSL) Tells curl to use the specified certificate directory to verify the peer. The certificates must be in PEM format.
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 to better enable scripts etc to better deal with failed
attempts. In normal cases when a HTTP server fails to deliver a document, it returns an HTML document stating so (which often also
describes why and more). This flag will prevent curl from outputting that and return error 22.
This method is not fail-safe and there are occasions where non-successful response codes will slip through, especially when authentica-
tion 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 ACCT
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 alterna-
tives:
multicwd
curl does a single CWD operation for each path part in the given URL. For deep hierarchies this means very many commands. This is
how RFC1738 says it should be done. This is the default but the slowest behavior.
nocwd curl does no CWD at all. curl will do SIZE, RETR, STOR etc and give a full path to the server for all these commands. This is the
fastest behavior.
singlecwd
curl does one CWD with the full target directory and then operates on the file "normally" (like in the multicwd case). This is
somewhat more standards compliant than ’nocwd’ but without the full penalty of ’multicwd’.
(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_/_-_f_t_p_-_p_o_r_t 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_/_-_-_f_t_p_-_p_o_r_t again.
Passive mode means that curl will try the EPSV command first and then PASV, unless _-_-_d_i_s_a_b_l_e_-_e_p_s_v is used.
--ftp-alternative-to-user <command>
(FTP) If authenticating with the USER and PASS commands fails, send this command. When connecting to Tumbleweed’s Secure Transport
server over FTPS using a client certificate, using "SITE AUTH" will tell the server to retrieve the username from the certificate. (Added
in 7.15.5)
--ftp-skip-pasv-ip
(FTP) Tell curl to not use the IP address the server suggests in its response to curl’s PASV command when curl connects the data connec-
tion. Instead curl will re-use the same IP address it already uses for the control connection. (Added in 7.14.2)
This option has no effect if PORT, EPRT or EPSV is used instead of PASV.
--ftp-ssl
(FTP) Try to use SSL/TLS for the FTP connection. Reverts to a non-secure connection if the server doesn’t support SSL/TLS. See also
_-_-_f_t_p_-_s_s_l_-_c_o_n_t_r_o_l and _-_-_f_t_p_-_s_s_l_-_r_e_q_d for different levels of encryption required. (Added in 7.11.0)
--ftp-ssl-control
(FTP) Require SSL/TLS for the FTP login, clear for transfer. Allows secure authentication, but non-encrypted data transfers for effi-
ciency. Fails the transfer if the server doesn’t support SSL/TLS. (Added in 7.16.0)
--ftp-ssl-reqd
(FTP) Require SSL/TLS for the FTP connection. Terminates the connection if the server doesn’t support SSL/TLS. (Added in 7.15.5)
--ftp-ssl-ccc
(FTP) Use CCC (Clear Command Channel) Shuts down the SSL/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 CCC (Clear Command Channel) Sets the CCC 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 <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 RFC2388. 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 differ-
ence 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:
ccuurrll -F password=@/etc/passwd www.mypasswords.com
To read the file’s content from stdin instead of a file, use - where the file name should’ve been. This goes for both @ and < constructs.
You can also tell curl what Content-Type to use by using ’type=’, in a manner similar to:
ccuurrll -F "web=@index.html;type=text/html" url.com
or
ccuurrll -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:
ccuurrll -F "file=@localfile;filename=nameinpost" url.com
See further examples and details in the MANUAL.
This option can be used multiple times.
--form-string <name=string>
(HTTP) Similar to _-_-_f_o_r_m 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 _-_-_f_o_r_m if there’s any possibility that the string value
may accidentally trigger the ’@’ or ’<’ features of _-_-_f_o_r_m.
-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_/_-_-_d_a_t_a or _-_-_d_a_t_a_-_b_i_n_a_r_y to be used in a HTTP GET request instead of the POST
request that otherwise would be used. The data will be appended to the URL with a ’?’ separator.
If used in combination with -I, the POST data will instead be appended to the URL with a HEAD request.
If this option is used several times, the following occurrences make no difference. 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.
-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 know-
ing 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 nnoott 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_/_-_-_u_s_e_r_-_a_g_e_n_t and _-_e_/_-_-_r_e_f_e_r_e_r options.
This option can be used multiple times to add/replace/remove multiple headers.
--hostpubmd5 <md5>
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
(HTTP) Ignore the Content-Length header. This is particularly useful for servers running Apache 1.x, which will report incorrect Content-
Length for files larger than 2 gigabytes.
-i/--include
(HTTP) Include the HTTP-header in the output. The HTTP-header includes things like server-name, date of the document, HTTP-version and
more...
--interface <name>
Perform an operation using a specified interface. You can enter interface name, IP address or host name. An example could look like:
curl --interface eth0:1 http://www.netscape.com/
If this option is used several times, the last one will be used.
-I/--head
(HTTP/FTP/FILE) Fetch the HTTP-header only! HTTP-servers feature the command HEAD which this uses to get nothing but the header of a doc-
ument. When used on a FTP or FILE file, curl displays the file size and last modification time only.
-j/--junk-session-cookies
(HTTP) When curl is told to read cookies from a given file, this option will make it discard all "session cookies". This will basically
have the same effect as if a new session is started. Typical browsers always discard session cookies when they’re closed down.
-k/--insecure
(SSL) This option explicitly allows curl to perform "insecure" SSL connections and transfers. All SSL connections are attempted to be
made secure by using the CA certificate bundle installed by default. This makes all connections considered "insecure" fail unless
_-_k_/_-_-_i_n_s_e_c_u_r_e is used.
See this online resource for further details: hhttttpp::////ccuurrll..hhaaxxxx..ssee//ddooccss//ssssllcceerrttss..hhttmmll
--keepalive-time <seconds>
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 TCP_KEEPIDLE and TCP_KEEPINTVL socket options (meaning Linux, recent
AIX, HP-UX and more). This option has no effect if _-_-_n_o_-_k_e_e_p_a_l_i_v_e is used. (Added in 7.18.0)
If this option is used multiple times, the last occurrence sets the amount.
--key <key>
(SSL/SSH) Private key file name. Allows you to provide your private key in this separate file.
If this option is used several times, the last one will be used.
--key-type <type>
(SSL) Private key file type. Specify which type your _-_-_k_e_y 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.
--krb <level>
(FTP) Enable Kerberos authentication and use. The level must be entered and should be one of ’clear’, ’safe’, ’confidential’, or ’pri-
vate’. 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 GSSAPI (GSS-Negotiate) support. This is not very common. Use _-_V_/_-_-_v_e_r_s_i_o_n to see
if your curl supports it.
If this option is used several times, the last one will be used.
-K/--config <config file>
Specify which config file to read curl arguments from. The config file is a text file in which command line arguments can be written
which then will be used as if they were written on the actual command line. Options and their parameters must be specified on the same
config file line, separated by whitespace, colon, the equals sign or any combination thereof (however, the preferred separator is the
equals sign). If the parameter is to contain whitespace, the parameter must be enclosed within quotes. Within double quotes, the follow-
ing 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 con-
fig 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 _-_-_u_r_l 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 CURL_HOME and then the HOME environment variables. Failing that, it uses
getpwuid() on UNIX-like systems (which returns the home dir given the current user in your system). On Windows, it then checks for the
APPDATA variable, or as a last resort the ’%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 executable 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 <file>
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 nec-
essary calls to _c_u_r_l___f_o_r_m_a_d_d_(_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 <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 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.
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_/_-_-_s_p_e_e_d_-_l_i_m_i_t option, that option will take precedence and might cripple the rate-limiting slightly, to help keep-
ing 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 sub-
directories and symbolic links.
--local-port <num>[-num]
Set a preferred number or range of local port numbers to use for the connection(s). Note that port numbers by nature 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
(HTTP/HTTPS) If the server reports that the requested page has moved to a different location (indicated with a Location: header and a 3XX
response code), this option will make curl redo the request on the new place. If used together with _-_i_/_-_-_i_n_c_l_u_d_e or _-_I_/_-_-_h_e_a_d, headers
from all requested pages will be shown. When authentication is used, curl only sends its credentials to the initial host. If a redirect
takes curl to a different host, it won’t be able to intercept the user+password. See also _-_-_l_o_c_a_t_i_o_n_-_t_r_u_s_t_e_d on how to change this. You
can limit the amount of redirects to follow by using the _-_-_m_a_x_-_r_e_d_i_r_s 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 HTTP response was 301, 302, or 303. If the response code was any other 3xx code, curl will re-send the following request using the
same unmodified method.
--location-trusted
(HTTP/HTTPS) Like _-_L_/_-_-_l_o_c_a_t_i_o_n, 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 plaintext in
the case of HTTP Basic authentication).
--max-filesize <bytes>
Specify the maximum size (in bytes) of a file to download. If the file requested is larger than this value, the transfer will not start
and curl will return with exit code 63.
NNOOTTEE:: The file size is not always known prior to download, and for such files this option has no effect even if the file transfer ends up
being larger than this given limit. This concerns both FTP and HTTP transfers.
-m/--max-time <seconds>
Maximum time in seconds that you allow the whole operation to take. This is useful for preventing your batch jobs from hanging for hours
due to slow networks or links going down. See also the _-_-_c_o_n_n_e_c_t_-_t_i_m_e_o_u_t 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 _._n_e_t_r_c (___n_e_t_r_c 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 HTTP, curl will enable user authentication. See nneettrrcc((44)) or ffttpp((11)) 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 _._n_e_t_r_c to allow curl to FTP to the machine host.domain.com with user name ’myself’ and
password ’secret’ should look similar to:
mmaacchhiinnee hhoosstt..ddoommaaiinn..ccoomm llooggiinn mmyysseellff ppaasssswwoorrdd sseeccrreett
--netrc-optional
Very similar to _-_-_n_e_t_r_c, but this option makes the .netrc usage ooppttiioonnaall and not mandatory as the _-_-_n_e_t_r_c option does.
--negotiate
(HTTP) Enables GSS-Negotiate authentication. The GSS-Negotiate method was designed by Microsoft and is used in their web applications. It
is primarily meant as a support for Kerberos5 authentication but may be also used along with another authentication method. For more
information see IETF draft draft-brezak-spnego-http-04.txt.
If you want to enable Negotiate for your proxy authentication, then use _-_-_p_r_o_x_y_-_n_e_g_o_t_i_a_t_e.
This option requires a library built with GSSAPI support. This is not very common. Use _-_V_/_-_-_v_e_r_s_i_o_n to see if your version supports GSS-
Negotiate.
When using this option, you must also provide a fake -u/--user option to activate the authentication code properly. Sending a ’-u :’ is
enough as the user name and password from the -u option aren’t actually used.
If this option is used several times, the following occurrences make no difference.
-N/--no-buffer
Disables the buffering of the output stream. In normal work situations, curl will use a standard buffered output stream that will have
the effect that it will output the data in chunks, not necessarily exactly when the data arrives. Using this option will disable that
buffering.
Note that this is the negated option name documented. You can thus use _-_-_b_u_f_f_e_r to enforce the buffering.
--no-keepalive
Disables the use of keepalive messages on the TCP connection, as by default curl enables them.
Note that this is the negated option name documented. You can thus use _-_-_k_e_e_p_a_l_i_v_e to enforce keepalive.
--no-sessionid
(SSL) Disable curl’s use of SSL session-ID caching. By default all transfers are done using the cache. Note that while nothing should
ever get hurt by attempting to reuse SSL session-IDs, there seem to be broken SSL 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 _-_-_s_e_s_s_i_o_n_i_d to enforce session-ID caching.
--noproxy <no-proxy-list>
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 (HTTP) Enables NTLM authentication. The NTLM authentication method was designed by Microsoft and is used by IIS web servers. It is a pro-
prietary 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 authentication, then use _-_-_p_r_o_x_y_-_n_t_l_m.
This option requires a library built with SSL support. Use _-_V_/_-_-_v_e_r_s_i_o_n to see if your curl supports NTLM.
If this option is used several times, the following occurrences make no difference.
-o/--output <file>
Write output to <file> instead of stdout. If you are using {} or [] to fetch multiple documents, you can use ’#’ followed by a number in
the <file> specifier. That variable will be replaced with the current string for the URL being fetched. Like in:
curl http://{one,two}.site.com -o "file_#1.txt"
or use several variables like:
curl http://{site,host}.host[1-5].com -o "#1_#2"
You may use this option as many times as the number of URLs you have.
See also the _-_-_c_r_e_a_t_e_-_d_i_r_s 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_/_-_-_r_e_m_o_t_e_-_n_a_m_e were used for each one. So if you want
to disable that for a specific URL after _-_-_r_e_m_o_t_e_-_n_a_m_e_-_a_l_l has been used, you must use "-o -" or _-_-_n_o_-_r_e_m_o_t_e_-_n_a_m_e. (Added in 7.19.0)
--pass <phrase>
(SSL/SSH) 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_/_-_-_l_o_c_a_t_i_o_n (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_/_-_-_l_o_c_a_t_i_o_n (Added in 7.19.1)
--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 HTTP Basic authentication when communicating with the given proxy. Use _-_-_b_a_s_i_c for enabling HTTP Basic with a remote
host. Basic is the default authentication method curl uses with proxies.
--proxy-digest
Tells curl to use HTTP Digest authentication when communicating with the given proxy. Use _-_-_d_i_g_e_s_t for enabling HTTP Digest with a remote
host.
--proxy-negotiate
Tells curl to use HTTP Negotiate authentication when communicating with the given proxy. Use _-_-_n_e_g_o_t_i_a_t_e for enabling HTTP Negotiate with
a remote host. (Added in 7.17.1)
--proxy-ntlm
Tells curl to use HTTP NTLM authentication when communicating with the given proxy. Use _-_-_n_t_l_m for enabling NTLM with a remote host.
--proxy1.0 <proxyhost[:port]>
Use the specified HTTP 1.0 proxy. If the port number is not specified, it is assumed at port 1080.
The only difference between this and the HTTP proxy option (_-_x_/_-_-_p_r_o_x_y), is that attempts to use CONNECT through the proxy will specify
an HTTP 1.0 protocol instead of the default HTTP 1.1.
-p/--proxytunnel
When an HTTP proxy is used (_-_x_/_-_-_p_r_o_x_y), this option will cause non-HTTP protocols to attempt to tunnel through the proxy instead of
merely using it to do HTTP-like operations. The tunnel approach is made with the HTTP proxy CONNECT request and requires that the proxy
allows direct connect to the remote port number curl wants to tunnel through to.
--pubkey <key>
(SSH) 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.
-P/--ftp-port <address>
(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. <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 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 _-_-_f_t_p_-_p_a_s_v. Disable the attempt to use the EPRT
command instead of PORT by using _-_-_d_i_s_a_b_l_e_-_e_p_r_t. EPRT is really PORT++.
Starting in 7.19.5, you can append ":[start]-[end]" to the right of the address, to tell curl what TCP port range to use. That means you specify
a port range, from a lower to a higher number. A single number works as well, but do note that it increases the risk of failure since the port
may not be available.
-q If used as the first parameter on the command line, the _c_u_r_l_r_c config file will not be read and used. See the _-_K_/_-_-_c_o_n_f_i_g for details on
the default config file search path.
-Q/--quote <command>
(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 command 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 libcurl 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 commands 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 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 specified 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 source_file target_file
The ln and symlink commands create a symbolic link at the target_file location pointing to the source_file location.
mkdir directory_name
The mkdir command creates the directory named by the directory_name 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 source_file target_file
See ln.
--random-file <file>
(SSL) 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 _-_-_e_g_d_-_f_i_l_e option.
-r/--range <range>
(HTTP/FTP/SFTP/FILE) Retrieve a byte range (i.e a partial document) from a HTTP/1.1, FTP or SFTP server or a local FILE. Ranges can be
specified in a number of ways.
00--449999 specifies the first 500 bytes
550000--999999 specifies the second 500 bytes
--550000 specifies the last 500 bytes
99550000-- specifies the bytes from offset 9500 and forward
00--00,,--11 specifies the first and last byte only(*)(H)
550000--770000,,660000--779999
specifies 300 bytes from offset 500(H)
110000--119999,,550000--559999
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 configuration.
You should also be aware that many HTTP/1.1 servers do not have this feature enabled, so that when you attempt to get a range, you’ll instead
get the whole document.
FTP 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 HTTP 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 the timestamp of the remote file, and if that is available make the local file
get that same timestamp.
--retry <num>
If a transient error is returned when curl tries to perform a transfer, it will retry this number of times before giving up. Setting the
number to 0 makes curl do no retries (which is the default). Transient error means either: a timeout, an FTP 5xx response code or an HTTP
5xx response code.
When curl is about to retry a transfer, it will first wait one second and then for all forthcoming retries it will double the waiting
time until it reaches 10 minutes which then will be the delay between the rest of the retries. By using _-_-_r_e_t_r_y_-_d_e_l_a_y you disable this
exponential backoff algorithm. See also _-_-_r_e_t_r_y_-_m_a_x_-_t_i_m_e to limit the total time allowed for retries. (Added in 7.12.3)
If this option is used multiple times, the last occurrence decide the amount.
--retry-delay <seconds>
Make curl sleep this amount of time 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 _-_-_r_e_t_r_y 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 <seconds>
The retry timer is reset before the first transfer attempt. Retries will be done as usual (see _-_-_r_e_t_r_y) 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_/_-_-_m_a_x_-_t_i_m_e. 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 or quiet mode. Don’t show progress meter or error messages. Makes Curl mute.
-S/--show-error
When used with -s it makes curl show an error message if it fails.
--socks4 <host[:port]>
Use the specified SOCKS4 proxy. If the port number is not specified, it is assumed at port 1080. (Added in 7.15.2)
This option overrides any previous use of _-_x_/_-_-_p_r_o_x_y, as they are mutually exclusive.
If this option is used several times, the last one will be used.
--socks4a <host[:port]>
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_/_-_-_p_r_o_x_y, as they are mutually exclusive.
If this option is used several times, the last one will be used.
--socks5-hostname <host[:port]>
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_/_-_-_p_r_o_x_y, 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 with-
out the number appended.)
--socks5 <host[:port]>
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_/_-_-_p_r_o_x_y, 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 with-
out the number appended.)
This option (as well as _-_-_s_o_c_k_s_4) does not work with IPV6, FTPS or LDAP.
--socks5-gssapi-service <servicename>
The default service name for a socks server is rcmd/server-fqdn. This option allows you to change it.
Examples:
--socks5 proxy-name _-_-_s_o_c_k_s_5_-_g_s_s_a_p_i_-_s_e_r_v_i_c_e sockd would use sockd/proxy-name
--socks5 proxy-name _-_-_s_o_c_k_s_5_-_g_s_s_a_p_i_-_s_e_r_v_i_c_e 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 implementation does not. The option _-_-_s_o_c_k_s_5_-_g_s_s_a_p_i_-_n_e_c allows the unprotected exchange of the protection mode negotia-
tion. (Added in 7.19.4).
--stderr <file>
Redirect all writes to stderr to the specified file instead. If the file name is a plain ’-’, it is instead written to stdout. This
option has no point when you’re using a shell with decent redirecting capabilities.
If this option is used several times, the last one will be used.
--tcp-nodelay
Turn on the TCP_NODELAY option. See the _c_u_r_l___e_a_s_y___s_e_t_o_p_t_(_3_) man page for details about this option. (Added in 7.11.2)
-t/--telnet-option <OPT=val>
Pass options to the telnet protocol. Supported options are:
TTYPE=<term> Sets the terminal type.
XDISPLOC=<X display> Sets the X display location.
NEW_ENV=<var,val> Sets an environment variable.
-T/--upload-file <file>
This transfers the specified local file to the remote URL. If there is no file part in the specified URL, Curl will append the local file
name. NOTE that you must use a trailing / on the last directory to really prove to Curl that there is no file name or curl will think
that your last directory name is the remote file name to use. That will most likely cause the upload operation to fail. If this is used
on a HTTP(S) server, the PUT command will be used.
Use the file name "-" (a single dash) to use stdin instead of a given file. Alternately, the file name "." (a single period) may be
specified instead of "-" to use stdin in non-blocking mode to allow reading server output while stdin is being uploaded.
You can specify one -T for each URL on the command line. Each -T + URL pair specifies what to upload and to where. curl also supports
"globbing" of the -T argument, meaning that you can upload multiple files to a single URL by using the same URL globbing style supported
in the URL, like this:
curl -T "{file1,file2}" http://www.uploadtothissite.com
or even
curl -T "img[1-1000].png" ftp://ftp.picturemania.com/upload/
--trace <file>
Enables a full trace dump of all incoming and outgoing data, including descriptive information, to the given output file. Use "-" as
filename to have the output sent to stdout.
This option overrides previous uses of _-_v_/_-_-_v_e_r_b_o_s_e or _-_-_t_r_a_c_e_-_a_s_c_i_i.
If this option is used several times, the last one will be used.
--trace-ascii <file>
Enables a full trace dump of all incoming and outgoing data, including descriptive information, to the given output file. Use "-" as
filename to have the output sent to stdout.
This is very similar to _-_-_t_r_a_c_e, 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.
This option overrides previous uses of _-_v_/_-_-_v_e_r_b_o_s_e or _-_-_t_r_a_c_e.
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)
-u/--user <user:password>
Specify the user name and password to use for server authentication. Overrides _-_n_/_-_-_n_e_t_r_c and _-_-_n_e_t_r_c_-_o_p_t_i_o_n_a_l.
If you just give the user name (without entering a colon) curl will prompt for a password.
If you use an SSPI-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 <user:password>
Specify the user name and password to use for proxy authentication.
If you use an SSPI-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 <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_/_-_-_o_u_t_p_u_t or the _-_O_/_-_-_r_e_m_o_t_e_-_n_a_m_e options.
-v/--verbose
Makes the fetching more verbose/talkative. Mostly useful 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 HTTP headers in the output, _-_i_/_-_-_i_n_c_l_u_d_e might be the option you’re looking for.
If you think this option still doesn’t give you enough details, consider using _-_-_t_r_a_c_e or _-_-_t_r_a_c_e_-_a_s_c_i_i instead.
This option overrides previous uses of _-_-_t_r_a_c_e_-_a_s_c_i_i or _-_-_t_r_a_c_e.
Use _-_s_/_-_-_s_i_l_e_n_t to make curl quiet.
-V/--version
Displays information about curl and the libcurl version it uses.
The first line includes the full version of curl, libcurl and other 3rd party libraries linked with the executable.
The second line (starts with "Protocols:") shows all protocols that libcurl reports to support.
The third line (starts with "Features:") shows specific features libcurl reports to offer. Available features include:
IPv6 You can use IPv6 with this.
krb4 Krb4 for FTP is supported.
SSL HTTPS and FTPS are supported.
libz Automatic decompression of compressed files over HTTP is supported.
NTLM NTLM authentication is supported.
GSS-Negotiate
Negotiate authentication and krb5 for FTP is supported.
Debug This curl uses a libcurl built with Debug. This enables more error-tracking and memory debugging etc. For curl-developers only!
AsynchDNS
This curl uses asynchronous name resolves.
SPNEGO SPNEGO Negotiate authentication is supported.
Largefile
This curl supports transfers of large files, files larger than 2GB.
IDN This curl supports IDN - international domain names.
SSPI SSPI is supported. If you use NTLM and set a blank user name, curl will authenticate with your current user and password.
-w/--write-out <format>
Defines what to display on stdout after a completed and successful operation. The format is a string that may contain plain text mixed
with any number of variables. The string can be specified as "string", to get read from a particular file you specify it "@filename" and
to tell curl to read the format from stdin you write "@-".
The variables present in the output format will be substituted by the value or text that curl thinks fit, as described below. All vari-
ables are specified as %{variable_name} and to output a normal % you just write them as %%. You can output a newline by using \n, a car-
riage return with \r and a tab space with \t.
NNOOTTEE:: 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:
uurrll__eeffffeeccttiivvee The URL that was fetched last. This is most meaningful if you’ve told curl to follow location: headers.
hhttttpp__ccooddee The numerical response code that was found in the last retrieved HTTP(S) or FTP(s) transfer. In 7.18.2 the alias
rreessppoonnssee__ccooddee was added to show the same info.
hhttttpp__ccoonnnneecctt The numerical code that was found in the last response (from a proxy) to a curl CONNECT request. (Added in 7.12.4)
ttiimmee__ttoottaall The total time, in seconds, that the full operation lasted. The time will be displayed with millisecond resolution.
ttiimmee__nnaammeellooookkuupp
The time, in seconds, it took from the start until the name resolving was completed.
ttiimmee__ccoonnnneecctt The time, in seconds, it took from the start until the TCP connect to the remote host (or proxy) was completed.
ttiimmee__aappppccoonnnneecctt
The time, in seconds, it took from the start until the SSL/SSH/etc connect/handshake to the remote host was completed.
(Added in 7.19.0)
ttiimmee__pprreettrraannssffeerr
The time, in seconds, it took from the start until the file transfer was just about to begin. This includes all pre-trans-
fer commands and negotiations that are specific to the particular protocol(s) involved.
ttiimmee__rreeddiirreecctt The time, in seconds, it took for all redirection steps include name lookup, connect, pretransfer and transfer before the
final transaction was started. time_redirect shows the complete execution time for multiple redirections. (Added in
7.12.3)
ttiimmee__ssttaarrttttrraannssffeerr
The time, in seconds, it took from the start until the first byte was just about to be transferred. This includes
time_pretransfer and also the time the server needed to calculate the result.
ssiizzee__ddoowwnnllooaadd The total amount of bytes that were downloaded.
ssiizzee__uuppllooaadd The total amount of bytes that were uploaded.
ssiizzee__hheeaaddeerr The total amount of bytes of the downloaded headers.
ssiizzee__rreeqquueesstt The total amount of bytes that were sent in the HTTP request.
ssppeeeedd__ddoowwnnllooaadd The average download speed that curl measured for the complete download.
ssppeeeedd__uuppllooaadd The average upload speed that curl measured for the complete upload.
ccoonntteenntt__ttyyppee The Content-Type of the requested document, if there was any.
nnuumm__ccoonnnneeccttss Number of new connects made in the recent transfer. (Added in 7.12.3)
nnuumm__rreeddiirreeccttss Number of redirects that were followed in the request. (Added in 7.12.3)
rreeddiirreecctt__uurrll When a HTTP request was made without -L to follow redirects, this variable will show the actual URL a redirect _w_o_u_l_d take
you to. (Added in 7.18.2)
ffttpp__eennttrryy__ppaatthh The initial path libcurl ended up in when logging on to the remote FTP server. (Added in 7.15.4)
ssssll__vveerriiffyy__rreessuulltt
The result of the SSL 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 <proxyhost[:port]>
Use the specified HTTP 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.
NNoottee that all operations that are performed over a HTTP proxy will transparently be converted to HTTP. It means that certain protocol
specific operations might not be available. This is not the case if you can tunnel through the proxy, as done with the _-_p_/_-_-_p_r_o_x_y_t_u_n_n_e_l
option.
Starting with 7.14.1, the proxy host can be specified the exact same way as the proxy environment variables, including the protocol pre-
fix (http://) and the embedded user + password.
If this option is used several times, the last one will be used.
-X/--request <command>
(HTTP) Specifies a custom request method to use when communicating with the HTTP server. The specified request will be used instead of
the method otherwise used (which defaults to GET). Read the HTTP 1.1 specification for details and explanations. Common additional HTTP
requests include PUT and DELETE, but related technologies like WebDAV offers PROPFIND, COPY, MOVE and more.
(FTP) Specifies a custom FTP command to use instead of LIST when doing file lists with FTP.
If this option is used several times, the last one will be used.
-y/--speed-time <time>
If a download is slower than speed-limit bytes per second during a speed-time period, the download gets aborted. If speed-time is used,
the default speed-limit will be 1 unless set with -Y.
This option controls transfers and thus will not affect slow connects etc. If this is a concern for you, try the _-_-_c_o_n_n_e_c_t_-_t_i_m_e_o_u_t
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/FTP) Request a file that has been modified later than the given time and date, or one that has been modified before that time. The
date expression can be all sorts of date strings or if it doesn’t match any internal ones, it tries to get the time from a given file
name instead! See the _c_u_r_l___g_e_t_d_a_t_e_(_3_) man pages for date expression details.
Start the date expression with a dash (-) to make it request for a document that is older than the given date/time, default is a document
that is newer than the specified date/time.
If this option is used several times, the last one will be used.
--max-redirs <num>
Set maximum number of redirection-followings allowed. If _-_L_/_-_-_l_o_c_a_t_i_o_n is used, this option can be used to prevent curl from following
redirections "in absurdum". By default, the limit is set to 50 redirections. Set this option to -1 to make it limitless.
If this option is used several times, the last one will be used.
-0/--http1.0
(HTTP) Forces curl to issue its requests using HTTP 1.0 instead of using its internally preferred: HTTP 1.1.
-1/--tlsv1
(SSL) Forces curl to use TLS version 1 when negotiating with a remote TLS server.
-2/--sslv2
(SSL) Forces curl to use SSL version 2 when negotiating with a remote SSL server.
-3/--sslv3
(SSL) Forces curl to use SSL version 3 when negotiating with a remote SSL server.
-4/--ipv4
If libcurl is capable of resolving an address to multiple IP versions (which it is if it is IPv6-capable), this option tells libcurl to
resolve names to IPv4 addresses only.
-6/--ipv6
If libcurl is capable of resolving an address to multiple IP versions (which it is if it is IPv6-capable), this option tells libcurl to
resolve names to IPv6 addresses only.
-#/--progress-bar
Make curl display progress information as a progress bar instead of the default statistics.
FFIILLEESS
_~_/_._c_u_r_l_r_c
Default config file, see _-_K_/_-_-_c_o_n_f_i_g for details.
EENNVVIIRROONNMMEENNTT
The environment variables can be specified in lower case or upper case. The lower case version has precedence. http_proxy is an exception as it
is only available in lower case.
http_proxy [protocol://]<host>[:port]
Sets the proxy server to use for HTTP.
HTTPS_PROXY [protocol://]<host>[:port]
Sets the proxy server to use for HTTPS.
FTP_PROXY [protocol://]<host>[:port]
Sets the proxy server to use for FTP.
ALL_PROXY [protocol://]<host>[:port]
Sets the 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 ’*’ only, it matches all hosts.
EEXXIITT CCOODDEESS
There are 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 support for this protocol.
2 Failed to initialize.
3 URL malformed. The 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 or denied access to the particular resource or directory you wanted to reach. Most often you
tried to change to a directory that doesn’t exist on the server.
11 FTP weird PASS reply. Curl couldn’t parse the reply sent to the PASS 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.
17 FTP couldn’t set binary. Couldn’t change transfer method to binary.
18 Partial file. Only a part of the file was transferred.
19 FTP couldn’t download/access the given file, the RETR (or similar) command failed.
21 FTP quote error. A quote command returned error from the server.
22 HTTP page not retrieved. The requested url was not found or returned another error with the HTTP error code being 400 or above. This
return code only appears if _-_f_/_-_-_f_a_i_l is used.
23 Write error. Curl couldn’t write data to a local filesystem or similar.
25 FTP couldn’t STOR file. The server denied the STOR operation, used for FTP uploading.
26 Read error. Various reading problems.
27 Out of memory. A memory allocation request failed.
28 Operation timeout. The specified time-out period was reached according to the conditions.
30 FTP PORT failed. The PORT command failed. Not all FTP servers support the PORT command, try doing a transfer using PASV instead!
31 FTP couldn’t use REST. The REST command failed. This command is used for resumed FTP transfers.
33 HTTP range error. The range "command" didn’t work.
34 HTTP post error. Internal post-request generation error.
35 SSL connect error. The SSL handshaking failed.
36 FTP bad download resume. Couldn’t continue an earlier aborted download.
37 FILE couldn’t read file. Failed to open the file. Permissions?
38 LDAP cannot bind. LDAP bind operation failed.
39 LDAP search failed.
41 Function not found. A required LDAP function was not found.
42 Aborted by callback. An application told curl to abort the operation.
43 Internal error. A function was called with a bad parameter.
45 Interface error. A specified outgoing interface could not be used.
47 Too many redirects. When following redirects, curl hit the maximum amount.
48 Unknown TELNET option specified.
49 Malformed telnet option.
51 The peer’s SSL certificate or SSH MD5 fingerprint was not 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.
58 Problem with the local certificate.
59 Couldn’t use specified SSL cipher.
60 Peer certificate cannot be authenticated with known CA certificates.
61 Unrecognized transfer encoding.
62 Invalid LDAP URL.
63 Maximum file size exceeded.
64 Requested FTP SSL level failed.
65 Sending the data requires a rewind that failed.
66 Failed to initialise SSL Engine.
67 The user name, password, or similar was not accepted and curl failed to log in.
68 File not found on TFTP server.
69 Permission problem on TFTP server.
70 Out of disk space on TFTP server.
71 Illegal TFTP operation.
72 Unknown TFTP transfer ID.
73 File already exists (TFTP).
74 No such user (TFTP).
75 Character conversion failed.
76 Character conversion functions required.
77 Problem with reading the SSL CA cert (path? access rights?).
78 The resource referenced in the URL does not exist.
79 An unspecified error occurred during the SSH session.
80 Failed to shut down the SSL connection.
82 Could not load CRL file, missing or wrong format (added in 7.19.0).
83 Issuer check failed (added in 7.19.0).
XX More error codes will appear here in future releases. The existing ones are meant to never change.
AAUUTTHHOORRSS // CCOONNTTRRIIBBUUTTOORRSS
Daniel Stenberg is the main author, but the whole list of contributors is found in the separate THANKS file.
WWWWWW
http://curl.haxx.se
FFTTPP
ftp://ftp.sunet.se/pub/www/utilities/curl/
SSEEEE AALLSSOO
ffttpp(1), wwggeett(1)
Curl 7.19.0 10 July 2008 curl(1)