curl_easy_setopt
curl_easy_setopt(3) libcurl Manual curl_easy_setopt(3)
NAME
curl_easy_setopt - Set curl easy-session options
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLoption option, parameter);
DESCRIPTION
curl_easy_setopt() is used to tell libcurl how to behave. Most opera-
tions in libcurl have default actions, and by using the appropriate
options to curl_easy_setopt, you can change them. All options are set
with the option followed by a parameter. That parameter can be a long,
a function pointer or an object pointer, all depending on what the spe-
cific option expects. Read this manual carefully as bad input values
may cause libcurl to behave badly! You can only set one option in each
function call. A typical application uses many curl_easy_setopt() calls
in the setup phase.
NOTE: strings passed to libcurl as 'char *' arguments, will not be
copied by the library. Instead you should keep them available until
libcurl no longer needs them. Failing to do so will cause very odd
behavior or even crashes.
NOTE2: options set with this function call are valid for the forthcom-
ing data transfers that are performed when you invoke curl_easy_per-
form. The options are not in any way reset between transfers, so if
you want subsequent transfers with different options, you must change
them between the transfers.
The handle is the return code from a curl_easy_init(3) or
curl_easy_duphandle(3) call.
OPTIONS
The options are listed in a sort of random order, but you'll figure it
out!
CURLOPT_WRITEDATA
Data pointer to pass to the file write function. Note that if you
specify the CURLOPT_WRITEFUNCTION, this is the pointer you'll get
as input. If you don't use a callback, you must pass a 'FILE *' as
libcurl will pass this to fwrite() when writing data.
NOTE: If you're using libcurl as a win32 DLL, you MUST use the CUR-
LOPT_WRITEFUNCTION if you set this option or you will experience
crashes.
This option is also known with the older name CURLOPT_FILE.
CURLOPT_WRITEFUNCTION
Function pointer that should match the following prototype: size_t
function( void *ptr, size_t size, size_t nmemb, void *stream); This
function gets called by libcurl as soon as there is data available
that needs to be saved. The size of the data pointed to by ptr is
size multiplied with nmemb. Return the number of bytes actually
taken care of. If that amount differs from the amount passed to
your function, it'll signal an error to the library and it will
abort the transfer and return CURLE_WRITE_ERROR.
Set the stream argument with the CURLOPT_FILE option.
NOTE: you will be passed as much data as possible in all invokes,
but you cannot possibly make any assumptions. It may be one byte,
it may be thousands. The maximum amount of data that can be passed
to the write callback is defined in the curl.h header file:
CURL_MAX_WRITE_SIZE.
CURLOPT_READDATA
Data pointer to pass to the file read function. Note that if you
specify the CURLOPT_READFUNCTION, this is the pointer you'll get as
input. If you don't specify a read callback, this must be a valid
FILE *.
NOTE: If you're using libcurl as a win32 DLL, you MUST use a CUR-
LOPT_READFUNCTION if you set this option.
This option is also known with the older name CURLOPT_INFILE.
CURLOPT_READFUNCTION
Function pointer that should match the following prototype: size_t
function( void *ptr, size_t size, size_t nmemb, void *stream); This
function gets called by libcurl as soon as it needs to read data in
order to send it to the peer. The data area pointed at by the
pointer ptr may be filled with at most size multiplied with nmemb
number of bytes. Your function must return the actual number of
bytes that you stored in that memory area. Returning 0 will signal
end-of-file to the library and cause it to stop the current trans-
fer.
CURLOPT_INFILESIZE
When uploading a file to a remote site, this option should be used
to tell libcurl what the expected size of the infile is.
CURLOPT_URL
The actual URL to deal with. The parameter should be a char * to a
zero terminated string. The string must remain present until curl
no longer needs it, as it doesn't copy the string.
NOTE: this option is (the only one) required to be set before
curl_easy_perform(3) is called.
CURLOPT_PROXY
Set HTTP proxy to use. The parameter should be a char * to a zero
terminated string holding the host name or dotted IP address. To
specify port number in this string, append :[port] to the end of
the host name. The proxy string may be prefixed with [protocol]://
since any such prefix will be ignored. The proxy's port number may
optionally be specified with the separate option CURLOPT_PROXYPORT.
NOTE: when you tell the library to use a HTTP proxy, libcurl will
transparently convert operations to HTTP even if you specify a FTP
URL etc. This may have an impact on what other features of the
library you can use, such as CURLOPT_QUOTE and similar FTP
specifics that don't work unless you tunnel through the HTTP proxy.
Such tunneling is activated with CURLOPT_HTTPPROXYTUNNEL.
NOTE2: libcurl respects the environment variables http_proxy,
ftp_proxy, all_proxy etc, if any of those is set.
CURLOPT_PROXYPORT
Pass a long with this option to set the proxy port to connect to
unless it is specified in the proxy string CURLOPT_PROXY.
CURLOPT_HTTPPROXYTUNNEL
Set the parameter to non-zero to get the library to tunnel all
operations through a given HTTP proxy. Note that there is a big
difference between using a proxy and to tunnel through it. If you
don't know what this means, you probably don't want this tunneling
option. (Added in libcurl 7.3)
CURLOPT_VERBOSE
Set the parameter to non-zero to get the library to display a lot
of verbose information about its operations. Very useful for
libcurl and/or protocol debugging and understanding.
You hardly ever want this set in production use, you will almost
always want this when you debug/report problems.
CURLOPT_HEADER
A non-zero parameter tells the library to include the header in the
body output. This is only relevant for protocols that actually have
headers preceding the data (like HTTP).
CURLOPT_NOPROGRESS
A non-zero parameter tells the library to shut of the built-in
progress meter completely.
NOTE: future versions of libcurl is likely to not have any built-in
progress meter at all.
CURLOPT_NOBODY
A non-zero parameter tells the library to not include the body-part
in the output. This is only relevant for protocols that have sepa-
rate header and body parts.
CURLOPT_FAILONERROR
A non-zero parameter tells the library to fail silently if the HTTP
code returned is equal to or larger than 300. The default action
would be to return the page normally, ignoring that code.
CURLOPT_UPLOAD
A non-zero parameter tells the library to prepare for an upload.
The CURLOPT_INFILE and CURLOPT_INFILESIZE are also interesting for
uploads.
CURLOPT_POST
A non-zero parameter tells the library to do a regular HTTP post.
This is a normal application/x-www-form-urlencoded kind, which is
the most commonly used one by HTML forms. See the CURLOPT_POST-
FIELDS option for how to specify the data to post and CURLOPT_POST-
FIELDSIZE in how to set the data size. Starting with libcurl 7.8,
this option is obsolete. Using the CURLOPT_POSTFIELDS option will
imply this option.
CURLOPT_FTPLISTONLY
A non-zero parameter tells the library to just list the names of an
ftp directory, instead of doing a full directory listing that would
include file sizes, dates etc.
This causes an FTP NLST command to be sent. Beware that some FTP
servers list only files in their response to NLST; they do not
include subdirectories and symbolic links.
CURLOPT_FTPAPPEND
A non-zero parameter tells the library to append to the remote file
instead of overwrite it. This is only useful when uploading to a
ftp site.
CURLOPT_NETRC
This parameter controls the preference of libcurl between using
user names and passwords from your ~/.netrc file, relative to user
names and passwords in the URL supplied with CURLOPT_URL.
Note: libcurl uses a user name (and supplied or prompted password)
supplied with CURLOPT_USERPWD in preference to any of the options
controlled by this parameter.
Pass a long, set to one of the values described below.
CURL_NETRC_OPTIONAL
The use of your ~/.netrc file is optional, and information in
the URL is to be preferred. The file will be scanned with the
host and user name (to find the password only) or with the
host only, to find the first user name and password after that
machine, which ever information is not specified in the URL.
Undefined values of the option will have this effect.
CURL_NETRC_IGNORED
The library will ignore the file and use only the information
in the URL.
This is the default.
CURL_NETRC_REQUIRED
This value tells the library that use of the file is required,
to ignore the information in the URL, and to search the file
with the host only.
Only machine name, user name and password are taken into account
(init macros and similar things aren't supported).
Note: libcurl does not verify that the file has the correct proper-
ties set (as the standard Unix ftp client does). It should only be
readable by user.
CURLOPT_FOLLOWLOCATION
A non-zero parameter tells the library to follow any Location:
header that the server sends as part of a HTTP header.
NOTE: this means that the library will re-send the same request on
the new location and follow new Location: headers all the way until
no more such headers are returned. CURLOPT_MAXREDIRS can be used to
limit the number of redirects libcurl will follow.
CURLOPT_TRANSFERTEXT
A non-zero parameter tells the library to use ASCII mode for ftp
transfers, instead of the default binary transfer. For LDAP trans-
fers it gets the data in plain text instead of HTML and for win32
systems it does not set the stdout to binary mode. This option can
be usable when transferring text data between systems with differ-
ent views on certain characters, such as newlines or similar.
CURLOPT_PUT
A non-zero parameter tells the library to use HTTP PUT to transfer
data. The data should be set with CURLOPT_INFILE and CUR-
LOPT_INFILESIZE.
CURLOPT_USERPWD
Pass a char * as parameter, which should be [user name]:[password]
to use for the connection. If the password is left out, you will be
prompted for it. CURLOPT_PASSWDFUNCTION can be used to set your
own prompt function.
CURLOPT_PROXYUSERPWD
Pass a char * as parameter, which should be [user name]:[password]
to use for the connection to the HTTP proxy. If the password is
left out, you will be prompted for it. CURLOPT_PASSWDFUNCTION can
be used to set your own prompt function.
CURLOPT_RANGE
Pass a char * as parameter, which should contain the specified
range you want. It should be in the format "X-Y", where X or Y may
be left out. HTTP transfers also support several intervals, sepa-
rated with commas as in "X-Y,N-M". Using this kind of multiple
intervals will cause the HTTP server to send the response document
in pieces (using standard MIME separation techniques).
CURLOPT_ERRORBUFFER
Pass a char * to a buffer that the libcurl may store human readable
error messages in. This may be more helpful than just the return
code from the library. The buffer must be at least CURL_ERROR_SIZE
big.
Note: if the library does not return an error, the buffer may not
have been touched. Do not rely on the contents in those cases.
CURLOPT_TIMEOUT
Pass a long as parameter containing the maximum time in seconds
that you allow the libcurl transfer operation to take. Normally,
name lookups can take a considerable time and limiting operations
to less than a few minutes risk aborting perfectly normal opera-
tions. This option will cause curl to use the SIGALRM to enable
time-outing system calls.
NOTE: this does not work in Unix multi-threaded programs, as it
uses signals.
CURLOPT_POSTFIELDS
Pass a char * as parameter, which should be the full data to post
in a HTTP post operation. This is a normal application/x-www-form-
urlencoded kind, which is the most commonly used one by HTML forms.
See also the CURLOPT_POST. Since 7.8, using CURLOPT_POSTFIELDS
implies CURLOPT_POST.
Note: to make multipart/formdata posts (aka rfc1867-posts), check
out the CURLOPT_HTTPPOST option.
CURLOPT_POSTFIELDSIZE
If you want to post data to the server without letting libcurl do a
strlen() to measure the data size, this option must be used. When
this option is used you can post fully binary data, which otherwise
is likely to fail. If this size is set to zero, the library will
use strlen() to get the size. (Added in libcurl 7.2)
CURLOPT_REFERER
Pass a pointer to a zero terminated string as parameter. It will be
used to set the Referer: header in the http request sent to the
remote server. This can be used to fool servers or scripts. You can
also set any custom header with CURLOPT_HTTPHEADER.
CURLOPT_USERAGENT
Pass a pointer to a zero terminated string as parameter. It will be
used to set the User-Agent: header in the http request sent to the
remote server. This can be used to fool servers or scripts. You can
also set any custom header with CURLOPT_HTTPHEADER.
CURLOPT_FTPPORT
Pass a pointer to a zero terminated string as parameter. It will be
used to get the IP address to use for the ftp PORT instruction. The
PORT instruction tells the remote server to connect to our speci-
fied IP address. The string may be a plain IP address, a host name,
an network interface name (under Unix) or just a '-' letter to let
the library use your systems default IP address. Default FTP opera-
tions are passive, and thus won't use PORT.
CURLOPT_LOW_SPEED_LIMIT
Pass a long as parameter. It contains the transfer speed in bytes
per second that the transfer should be below during CUR-
LOPT_LOW_SPEED_TIME seconds for the library to consider it too slow
and abort.
CURLOPT_LOW_SPEED_TIME
Pass a long as parameter. It contains the time in seconds that the
transfer should be below the CURLOPT_LOW_SPEED_LIMIT for the
library to consider it too slow and abort.
CURLOPT_RESUME_FROM
Pass a long as parameter. It contains the offset in number of bytes
that you want the transfer to start from.
CURLOPT_COOKIE
Pass a pointer to a zero terminated string as parameter. It will be
used to set a cookie in the http request. The format of the string
should be [NAME]=[CONTENTS]; Where NAME is the cookie name.
If you need to set mulitple cookies, you need to set them all using
a single option and thus you need to concat them all in one single
string. Set multiple cookies in one string like this: "name1=con-
tent1; name2=content2;" etc.
Using this option multiple times will only make the latest string
override the previously ones.
CURLOPT_HTTPHEADER
Pass a pointer to a linked list of HTTP headers to pass to the
server in your HTTP request. The linked list should be a fully
valid list of struct curl_slist structs properly filled in. Use
curl_slist_append(3) to create the list and curl_slist_free_all(3)
to clean up an entire list. If you add a header that is otherwise
generated and used by libcurl internally, your added one will be
used instead. If you add a header with no contents as in 'Accept:'
(no data on the right side of the colon), the internally used
header will get disabled. Thus, using this option you can add new
headers, replace internal headers and remove internal headers.
NOTE:The most commonly replaced headers have "shortcuts" in the
options CURLOPT_COOKIE, CURLOPT_USERAGENT and CURLOPT_REFERER.
CURLOPT_HTTPPOST
Tells libcurl you want a multipart/formdata HTTP POST to be made
and you instruct what data to pass on to the server. Pass a
pointer to a linked list of HTTP post structs as parameter. The
linked list should be a fully valid list of 'struct HttpPost'
structs properly filled in. The best and most elegant way to do
this, is to use curl_formadd(3) as documented. The data in this
list must remained intact until you close this curl handle again
with curl_easy_cleanup(3).
CURLOPT_SSLCERT
Pass a pointer to a zero terminated string as parameter. The string
should be the file name of your certificate. The default format is
"PEM" and can be changed with CURLOPT_SSLCERTTYPE.
CURLOPT_SSLCERTTYPE
Pass a pointer to a zero terminated string as parameter. The string
should be the format of your certificate. Supported formats are
"PEM" and "DER". (Added in 7.9.3)
CURLOPT_SSLCERTPASSWD
Pass a pointer to a zero terminated string as parameter. It will be
used as the password required to use the CURLOPT_SSLCERT
certificate. If the password is not supplied, you will be prompted
for it. CURLOPT_PASSWDFUNCTION can be used to set your own prompt
function.
NOTE:This option is replaced by CURLOPT_SSLKEYPASSWD and only cept
for backward compatibility. You never needed a pass phrase to load
a certificate but you need one to load your private key.
CURLOPT_SSLKEY
Pass a pointer to a zero terminated string as parameter. The string
should be the file name of your private key. The default format is
"PEM" and can be changed with CURLOPT_SSLKEYTYPE. (Added in 7.9.3)
CURLOPT_SSLKEYTYPE
Pass a pointer to a zero terminated string as parameter. The string
should be the format of your private key. Supported formats are
"PEM", "DER" and "ENG". (Added in 7.9.3)
NOTE:The format "ENG" enables you to load the private key from a
crypto engine. in this case CURLOPT_SSLKEY is used as an identifier
passed to the engine. You have to set the crypto engine with CUR-
LOPT_SSL_ENGINE.
CURLOPT_SSLKEYASSWD
Pass a pointer to a zero terminated string as parameter. It will be
used as the password required to use the CURLOPT_SSLKEY private
key. If the password is not supplied, you will be prompted for it.
CURLOPT_PASSWDFUNCTION can be used to set your own prompt function.
(Added in 7.9.3)
CURLOPT_SSL_ENGINE
Pass a pointer to a zero terminated string as parameter. It will be
used as the identifier for the crypto engine you want to use for
your private key. (Added in 7.9.3)
NOTE:If the crypto device cannot be loaded, CURLE_SSL_ENGINE_NOT-
FOUND is returned.
CURLOPT_SSL_ENGINEDEFAULT
Sets the actual crypto engine as the default for (asymetric) crypto
operations. (Added in 7.9.3)
NOTE:If the crypto device cannot be set, CURLE_SSL_ENGINE_SETFAILED
is returned.
CURLOPT_CRLF
Convert Unix newlines to CRLF newlines on FTP uploads.
CURLOPT_QUOTE
Pass a pointer to a linked list of FTP commands to pass to the
server prior to your ftp request. The linked list should be a fully
valid list of 'struct curl_slist' structs properly filled in. Use
curl_slist_append(3) to append strings (commands) to the list, and
clear the entire list afterwards with curl_slist_free_all(3). Dis-
able this operation again by setting a NULL to this option.
CURLOPT_POSTQUOTE
Pass a pointer to a linked list of FTP commands to pass to the
server after your ftp transfer request. The linked list should be a
fully valid list of struct curl_slist structs properly filled in as
described for CURLOPT_QUOTE. Disable this operation again by set-
ting a NULL to this option.
CURLOPT_WRITEHEADER
Pass a pointer to be used to write the header part of the received
data to. If you don't use your own callback to take care of the
writing, this must be a valid FILE *. See also the CURLOPT_HEADER-
FUNCTION option below on how to set a custom get-all-headers call-
back.
CURLOPT_HEADERFUNCTION
Function pointer that should match the following prototype: size_t
function( void *ptr, size_t size, size_t nmemb, void *stream);.
This function gets called by libcurl as soon as there is received
header data that needs to be written down. The headers are guaran-
teed to be written one-by-one and only complete lines are written.
Parsing headers should be easy enough using this. The size of the
data pointed to by ptr is size multiplied with nmemb. The pointer
named stream will be the one you passed to libcurl with the CUR-
LOPT_WRITEHEADER option. Return the number of bytes actually writ-
ten or return -1 to signal error to the library (it will cause it
to abort the transfer with a CURLE_WRITE_ERROR return code). (Added
in libcurl 7.7.2)
CURLOPT_COOKIEFILE
Pass a pointer to a zero terminated string as parameter. It should
contain the name of your file holding cookie data. The cookie data
may be in Netscape / Mozilla cookie data format or just regular
HTTP-style headers dumped to a file.
CURLOPT_SSLVERSION
Pass a long as parameter. Set what version of SSL to attempt to
use, 2 or 3. By default, the SSL library will try to solve this by
itself although some servers make this difficult why you at times
may have to use this option.
CURLOPT_TIMECONDITION
Pass a long as parameter. This defines how the CURLOPT_TIMEVALUE
time value is treated. You can set this parameter to TIME-
COND_IFMODSINCE or TIMECOND_IFUNMODSINCE. This is a HTTP-only fea-
ture. (TBD)
CURLOPT_TIMEVALUE
Pass a long as parameter. This should be the time in seconds since
1 jan 1970, and the time will be used in a condition as specified
with CURLOPT_TIMECONDITION.
CURLOPT_CUSTOMREQUEST
Pass a pointer to a zero terminated string as parameter. It will be
user instead of GET or HEAD when doing the HTTP request. This is
useful for doing DELETE or other more or less obscure HTTP
requests. Don't do this at will, make sure your server supports the
command first.
CURLOPT_STDERR
Pass a FILE * as parameter. This is the stream to use instead of
stderr internally when reporting errors.
CURLOPT_INTERFACE
Pass a char * as parameter. This set the interface name to use as
outgoing network interface. The name can be an interface name, an
IP address or a host name. (Added in libcurl 7.3)
CURLOPT_KRB4LEVEL
Pass a char * as parameter. Set the krb4 security level, this also
enables krb4 awareness. This is a string, 'clear', 'safe', 'confi-
dential' or 'private'. If the string is set but doesn't match one
of these, 'private' will be used. Set the string to NULL to disable
kerberos4. The kerberos support only works for FTP. (Added in
libcurl 7.3)
CURLOPT_PROGRESSFUNCTION
Function pointer that should match the curl_progress_callback pro-
totype found in <curl/curl.h>. This function gets called by libcurl
instead of its internal equivalent with a frequent interval during
data transfer. Unknown/unused argument values will be set to zero
(like if you only download data, the upload size will remain 0).
Returning a non-zero value from this callback will cause libcurl to
abort the transfer and return CURLE_ABORTED_BY_CALLBACK.
CURLOPT_PROGRESSDATA
Pass a pointer that will be untouched by libcurl and passed as the
first argument in the progress callback set with CURLOPT_PROGRESS-
FUNCTION.
CURLOPT_SSL_VERIFYPEER
Pass a long that is set to a non-zero value to make curl verify the
peer's certificate. The certificate to verify against must be spec-
ified with the CURLOPT_CAINFO option (Added in 7.4.2) or a certifi-
cate directory must be specified with the CURLOPT_CAPATH option
(Added in 7.9.8).
CURLOPT_CAINFO
Pass a char * to a zero terminated string naming a file holding one
or more certificates to verify the peer with. This only makes sense
when used in combination with the CURLOPT_SSL_VERIFYPEER option.
(Added in 7.4.2)
CURLOPT_CAPATH
Pass a char * to a zero terminated string naming a directory hold-
ing multiple CA certificates to verify the peer with. The certifi-
cate directory must be prepared using the openssl c_rehash utility.
This only makes sense when used in combination with the CUR-
LOPT_SSL_VERIFYPEER option. The CAPATH function apparently does not
work in Windows due to some limitation in openssl. (Added in 7.9.8)
CURLOPT_PASSWDFUNCTION
Pass a pointer to a curl_passwd_callback function that will be
called instead of the internal one if libcurl requests a password.
The function must match this prototype: int my_getpass(void
*client, char *prompt, char* buffer, int buflen );. If set to
NULL, it equals to making the function always fail. If the function
returns a non-zero value, it will abort the operation and an error
(CURLE_BAD_PASSWORD_ENTERED) will be returned. client is a generic
pointer, see CURLOPT_PASSWDDATA. prompt is a zero-terminated
string that is text that prefixes the input request. buffer is a
pointer to data where the entered password should be stored and
buflen is the maximum number of bytes that may be written in the
buffer. (Added in 7.4.2)
CURLOPT_PASSWDDATA
Pass a void * to whatever data you want. The passed pointer will be
the first argument sent to the specifed CURLOPT_PASSWDFUNCTION
function. (Added in 7.4.2)
CURLOPT_FILETIME
Pass a long. If it is a non-zero value, libcurl will attempt to get
the modification date of the remote document in this operation.
This requires that the remote server sends the time or replies to a
time querying command. The curl_easy_getinfo(3) function with the
CURLINFO_FILETIME argument can be used after a transfer to extract
the received time (if any). (Added in 7.5)
CURLOPT_MAXREDIRS
Pass a long. The set number will be the redirection limit. If that
many redirections have been followed, the next redirect will cause
an error (CURLE_TOO_MANY_REDIRECTS). This option only makes sense
if the CURLOPT_FOLLOWLOCATION is used at the same time. (Added in
7.5)
CURLOPT_MAXCONNECTS
Pass a long. The set number will be the persistant connection cache
size. The set amount will be the maximum amount of simultaneous
connections that libcurl may cache between file transfers. Default
is 5, and there isn't much point in changing this value unless you
are perfectly aware of how this work and changes libcurl's
behaviour.
NOTE: if you already have performed transfers with this curl han-
dle, setting a smaller MAXCONNECTS than before may cause open con-
nections to get closed unnecessarily. (Added in 7.7)
CURLOPT_CLOSEPOLICY
Pass a long. This option sets what policy libcurl should use when
the connection cache is filled and one of the open connections has
to be closed to make room for a new connection. This must be one of
the CURLCLOSEPOLICY_* defines. Use CURLCLOSEPOL-
ICY_LEAST_RECENTLY_USED to make libcurl close the connection that
was least recently used, that connection is also least likely to be
capable of re-use. Use CURLCLOSEPOLICY_OLDEST to make libcurl close
the oldest connection, the one that was created first among the
ones in the connection cache. The other close policies are not sup-
port yet. (Added in 7.7)
CURLOPT_FRESH_CONNECT
Pass a long. Set to non-zero to make the next transfer use a new
(fresh) connection by force. If the connection cache is full before
this connection, one of the existing connections will be closed as
according to the selected or default policy. This option should be
used with caution and only if you understand what it does. Set this
to 0 to have libcurl attempt re-using an existing connection
(default behavior). (Added in 7.7)
CURLOPT_FORBID_REUSE
Pass a long. Set to non-zero to make the next transfer explicitly
close the connection when done. Normally, libcurl keep all connec-
tions alive when done with one transfer in case there comes a suc-
ceeding one that can re-use them. This option should be used with
caution and only if you understand what it does. Set to 0 to have
libcurl keep the connection open for possibly later re-use (default
behavior). (Added in 7.7)
CURLOPT_RANDOM_FILE
Pass a char * to a zero terminated file name. The file will be used
to read from to seed the random engine for SSL. The more random the
specified file is, the more secure will the SSL connection become.
CURLOPT_EGDSOCKET
Pass a char * to the zero terminated path name to the Entropy Gath-
ering Daemon socket. It will be used to seed the random engine for
SSL.
CURLOPT_CONNECTTIMEOUT
Pass a long. It should contain the maximum time in seconds that you
allow the connection to the server to take. This only limits the
connection phase, once it has connected, this option is of no more
use. Set to zero to disable connection timeout (it will then only
timeout on the system's internal timeouts). See also the CUR-
LOPT_TIMEOUT option.
NOTE: this does not work in unix multi-threaded programs, as it
uses signals.
CURLOPT_HTTPGET
Pass a long. If the long is non-zero, this forces the HTTP request
to get back to GET. Only really usable if POST, PUT or a custom
request have been used previously using the same curl handle.
(Added in 7.8.1)
CURLOPT_SSL_VERIFYHOST
Pass a long. Set if we should verify the Common name from the peer
certificate in the SSL handshake, set 1 to check existence, 2 to
ensure that it matches the provided hostname. (Added in 7.8.1)
CURLOPT_COOKIEJAR
Pass a file name as char *, zero terminated. This will make libcurl
dump all internally known cookies to the specified file when
curl_easy_cleanup(3) is called. If no cookies are known, no file
will be created. Specify "-" to instead have the cookies written to
stdout.
CURLOPT_SSL_CIPHER_LIST
Pass a char *, pointing to a zero terminated string holding the
list of ciphers to use for the SSL connection. The list must be
syntactly correct, it consists of one or more cipher strings sepa-
rated by colons. Commas or spaces are also acceptable separators
but colons are normally used, , - and + can be used as operators.
Valid examples of cipher lists include 'RC4-SHA', 'SHA1+DES',
'TLSv1' and 'DEFAULT'. The default list is normally set when you
compile OpenSSL.
You'll find more details about cipher lists on this URL:
http://www.openssl.org/docs/apps/ciphers.html
CURLOPT_HTTP_VERSION
Pass a long, set to one of the values described below. They force
libcurl to use the specific HTTP versions. This is not sensible to
do unless you have a good reason.
CURL_HTTP_VERSION_NONE
We don't care about what version the library uses. libcurl
will use whatever it thinks fit.
CURL_HTTP_VERSION_1_0
Enforce HTTP 1.0 requests.
CURL_HTTP_VERSION_1_1
Enforce HTTP 1.1 requests.
CURLOPT_FTP_USE_EPSV
Pass a long. If the value is non-zero, it tells curl to use the
EPSV command when doing passive FTP downloads (which is always does
by default). Using EPSV means that it will first attempt to use
EPSV before using PASV, but if you pass FALSE (zero) to this
option, it will not try using EPSV, only plain PASV.
CURLOPT_DNS_CACHE_TIMEOUT
Pass a long, this sets the timeout in seconds. Name resolves will
be kept in memory for this number of seconds. Set to zero (0) to
completely disable caching, or set to -1 to make the cached entries
remain forever. By default, libcurl caches info for 60 seconds.
(Added in libcurl 7.9.3)
CURLOPT_DNS_USE_GLOBAL_CACHE
Pass a long. If the value is non-zero, it tells curl to use a
global DNS cache that will survive between easy handles creations
and deletions. This is not thread-safe and this will use a global
varible. (Added in libcurl 7.9.3)
CURLOPT_DEBUGFUNCTION
Function pointer that should match the following prototype: int
curl_debug_callback (CURL *, curl_infotype, char *, size_t, void
*); This function will receive debug information if CURLOPT_VERBOSE
is enabled. The curl_infotype argument specifies what kind of
information it is. This funtion must return 0.
CURLOPT_DEBUGDATA
Pass a pointer to whatever you want passed in to your CUR-
LOPT_DEBUGFUNCTION in the last void * argument. This pointer is not
used by libcurl, it is only passed to the callback.
RETURN VALUE
CURLE_OK (zero) means that the option was set properly, non-zero means
an error occurred as <curl/curl.h> defines. See the libcurl-errors.3
man page for the full list with descriptions.
SEE ALSO
curl_easy_init(3), curl_easy_cleanup(3),
BUGS
If you find any bugs, or just have questions, subscribe to one of the
mailing lists and post. We won't bite.
libcurl 7.9.8 28 May 2002 curl_easy_setopt(3)
