curl_easy_setopt.3

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existing for this "session" only.
.IP CURLOPT_COOKIELIST
Pass a char * to a cookie string. Cookie can be either in Netscape / Mozilla
format or just regular HTTP-style header (Set-Cookie: ...) format. If cURL
cookie engine was not enabled it will enable its cookie engine.  Passing a
magic string \&"ALL" will erase all cookies known by cURL. (Added in 7.14.1)
Passing the special string \&"SESS" will only erase all session cookies known
by cURL. (Added in 7.15.4)
.IP CURLOPT_HTTPGET
Pass a long. If the long is non-zero, this forces the HTTP request to get back
to GET. usable if a POST, HEAD, PUT or a custom request have been used
previously using the same curl handle.

When setting \fICURLOPT_HTTPGET\fP to a non-zero value, it will automatically
set \fICURLOPT_NOBODY\fP to 0 (since 7.14.1).
.IP 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.
.RS
.IP CURL_HTTP_VERSION_NONE
We don't care about what version the library uses. libcurl will use whatever
it thinks fit.
.IP CURL_HTTP_VERSION_1_0
Enforce HTTP 1.0 requests.
.IP CURL_HTTP_VERSION_1_1
Enforce HTTP 1.1 requests.
.IP CURLOPT_IGNORE_CONTENT_LENGTH
Ignore the Content-Length header. This is useful for Apache 1.x (and similar
servers) which will report incorrect content length for files over 2
gigabytes. If this option is used, curl will not be able to accurately report
progress, and will simply stop the download when the server ends the
connection. (added in 7.14.1)
.RE
.SH FTP OPTIONS
.IP 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 specified 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 operations are passive, and thus won't use PORT.

You disable PORT again and go back to using the passive version by setting
this option to NULL.
.IP CURLOPT_QUOTE
Pass a pointer to a linked list of FTP commands to pass to the server prior to
your ftp request. This will be done before any other FTP commands are issued
(even before the CWD command). The linked list should be a fully valid list of
'struct curl_slist' structs properly filled in. Use \fIcurl_slist_append(3)\fP
to append strings (commands) to the list, and clear the entire list afterwards
with \fIcurl_slist_free_all(3)\fP. Disable this operation again by setting a
NULL to this option.
.IP 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
\fICURLOPT_QUOTE\fP. Disable this operation again by setting a NULL to this
option.
.IP CURLOPT_PREQUOTE
Pass a pointer to a linked list of FTP commands to pass to the server after
the transfer type is set. The linked list should be a fully valid list of
struct curl_slist structs properly filled in as described for
\fICURLOPT_QUOTE\fP. Disable this operation again by setting a NULL to this
option.
.IP 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 might not include subdirectories
and symbolic links.
.IP 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 an ftp site.
.IP CURLOPT_FTP_USE_EPRT
Pass a long. If the value is non-zero, it tells curl to use the EPRT (and
LPRT) command when doing active FTP downloads (which is enabled by
\fICURLOPT_FTPPORT\fP). Using EPRT means that it will first attempt to use
EPRT and then LPRT before using PORT, but if you pass FALSE (zero) to this
option, it will not try using EPRT or LPRT, only plain PORT. (Added in 7.10.5)

If the server is an IPv6 host, this option will have no effect as of 7.12.3.
.IP 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 it 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.

If the server is an IPv6 host, this option will have no effect as of 7.12.3.
.IP CURLOPT_FTP_CREATE_MISSING_DIRS
Pass a long. If the value is non-zero, curl will attempt to create any remote
directory that it fails to CWD into. CWD is the command that changes working
directory. (Added in 7.10.7)
.IP CURLOPT_FTP_RESPONSE_TIMEOUT
Pass a long.  Causes curl to set a timeout period (in seconds) on the amount
of time that the server is allowed to take in order to generate a response
message for a command before the session is considered hung.  While curl is
waiting for a response, this value overrides \fICURLOPT_TIMEOUT\fP. It is
recommended that if used in conjunction with \fICURLOPT_TIMEOUT\fP, you set
\fICURLOPT_FTP_RESPONSE_TIMEOUT\fP to a value smaller than
\fICURLOPT_TIMEOUT\fP.  (Added in 7.10.8)
.IP CURLOPT_FTP_ALTERNATIVE_TO_USER
Pass a char * as parameter, pointing to a string which will be used to
authenticate if the usual FTP "USER user" and "PASS password" negotiation
fails. This is currently only known to be required when connecting to
Tumbleweed's Secure Transport FTPS server using client certificates for
authentication. (Added in 7.15.5)
.IP CURLOPT_FTP_SKIP_PASV_IP
Pass a long. If set to a non-zero value, it instructs libcurl to not use the
IP address the server suggests in its 227-response to libcurl's PASV command
when libcurl connects the data connection. Instead libcurl will re-use the
same IP address it already uses for the control connection. But it will use
the port number from the 227-response. (Added in 7.14.2)

This option has no effect if PORT, EPRT or EPSV is used instead of PASV.
.IP CURLOPT_FTP_SSL
Pass a long using one of the values from below, to make libcurl use your
desired level of SSL for the ftp transfer. (Added in 7.11.0)
.RS
.IP CURLFTPSSL_NONE
Don't attempt to use SSL.
.IP CURLFTPSSL_TRY
Try using SSL, proceed as normal otherwise.
.IP CURLFTPSSL_CONTROL
Require SSL for the control connection or fail with \fICURLE_FTP_SSL_FAILED\fP.
.IP CURLFTPSSL_ALL
Require SSL for all communication or fail with \fICURLE_FTP_SSL_FAILED\fP.
.RE
.IP CURLOPT_FTPSSLAUTH
Pass a long using one of the values from below, to alter how libcurl issues
\&"AUTH TLS" or "AUTH SSL" when FTP over SSL is activated (see
\fICURLOPT_FTP_SSL\fP). (Added in 7.12.2)
.RS
.IP CURLFTPAUTH_DEFAULT
Allow libcurl to decide
.IP CURLFTPAUTH_SSL
Try "AUTH SSL" first, and only if that fails try "AUTH TLS"
.IP CURLFTPAUTH_TLS
Try "AUTH TLS" first, and only if that fails try "AUTH SSL"
.RE
.IP CURLOPT_SOURCE_URL
When set, it enables a FTP third party transfer, using the set URL as source,
while \fICURLOPT_URL\fP is the target.
.IP CURLOPT_SOURCE_USERPWD
Set "username:password" to use for the source connection when doing FTP third
party transfers.
.IP CURLOPT_SOURCE_QUOTE
Exactly like \fICURLOPT_QUOTE\fP, but for the source host.
.IP CURLOPT_SOURCE_PREQUOTE
Exactly like \fICURLOPT_PREQUOTE\fP, but for the source host.
.IP CURLOPT_SOURCE_POSTQUOTE
Exactly like \fICURLOPT_POSTQUOTE\fP, but for the source host.
.IP CURLOPT_FTP_ACCOUNT
Pass a pointer to a zero-terminated string (or NULL to disable). 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)
.IP CURLOPT_FTP_FILEMETHOD
Pass a long that should have one of the following values. This option controls
what method libcurl should use to reach a file on a FTP(S) server. The
argument should be one of the following alternatives:
.RS
.IP CURLFTPMETHOD_MULTICWD
libcurl 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.
.IP CURLFTPMETHOD_NOCWD
libcurl does no CWD at all. libcurl will do SIZE, RETR, STOR etc and give a
full path to the server for all these commands. This is the fastest behavior.
.IP CURLFTPMETHOD_SINGLECWD
libcurl 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'.
.RE
.SH PROTOCOL OPTIONS
.IP CURLOPT_TRANSFERTEXT
A non-zero parameter tells the library to use ASCII mode for ftp transfers,
instead of the default binary transfer. For win32 systems it does not set the
stdout to binary mode. This option can be usable when transferring text data
between systems with different views on certain characters, such as newlines
or similar.

libcurl does not do a complete ASCII conversion when doing ASCII transfers
over FTP. This is a known limitation/flaw that nobody has rectified. libcurl
simply sets the mode to ascii and performs a standard transfer.
.IP CURLOPT_CRLF
Convert Unix newlines to CRLF newlines on transfers.
.IP 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, separated with commas as in
\fI"X-Y,N-M"\fP. Using this kind of multiple intervals will cause the HTTP
server to send the response document in pieces (using standard MIME separation
techniques). Pass a NULL to this option to disable the use of ranges.
.IP CURLOPT_RESUME_FROM
Pass a long as parameter. It contains the offset in number of bytes that you
want the transfer to start from. Set this option to 0 to make the transfer
start from the beginning (effectively disabling resume).
.IP CURLOPT_RESUME_FROM_LARGE
Pass a curl_off_t as parameter. It contains the offset in number of bytes that
you want the transfer to start from. (Added in 7.11.0)
.IP CURLOPT_CUSTOMREQUEST
Pass a pointer to a zero terminated string as parameter. It will be user
instead of GET or HEAD when doing an HTTP request, or instead of LIST or NLST
when doing an ftp directory listing. 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.

Restore to the internal default by setting this to NULL.

Many people have wrongly used this option to replace the entire request with
their own, including multiple headers and POST contents. While that might work
in many cases, it will cause libcurl to send invalid requests and it could
possibly confuse the remote server badly. Use \fICURLOPT_POST\fP and
\fICURLOPT_POSTFIELDS\fP to set POST data. Use \fICURLOPT_HTTPHEADER\fP to
replace or extend the set of headers sent by libcurl. Use
\fICURLOPT_HTTP_VERSION\fP to change HTTP version.
.IP 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
\fIcurl_easy_getinfo(3)\fP function with the \fICURLINFO_FILETIME\fP argument
can be used after a transfer to extract the received time (if any).
.IP 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 separate header and body
parts. On HTTP(S) servers, this will make libcurl do a HEAD request.

To change request to GET, you should use \fICURLOPT_HTTPGET\fP. Change request
to POST with \fICURLOPT_POST\fP etc.
.IP 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. This value should be passed
as a long. See also \fICURLOPT_INFILESIZE_LARGE\fP.
.IP CURLOPT_INFILESIZE_LARGE
When uploading a file to a remote site, this option should be used to tell
libcurl what the expected size of the infile is.  This value should be passed
as a curl_off_t. (Added in 7.11.0)
.IP CURLOPT_UPLOAD
A non-zero parameter tells the library to prepare for an upload. The
\fICURLOPT_READDATA\fP and \fICURLOPT_INFILESIZEE\fP or
\fICURLOPT_INFILESIZE_LARGE\fP are also interesting for uploads. If the
protocol is HTTP, uploading means using the PUT request unless you tell
libcurl otherwise.

Using PUT with HTTP 1.1 implies the use of a "Expect: 100-continue" header.
You can disable this header with \fICURLOPT_HTTPHEADER\fP as usual.

If you use PUT to a HTTP 1.1 server, you can upload data without knowing the
size before starting the transfer if you use chunked encoding. You enable this
by adding a header like "Transfer-Encoding: chunked" with
\fICURLOPT_HTTPHEADER\fP. With HTTP 1.0 or without chunked transfer, you must