h1-mod/deps/curl/docs/libcurl/opts/CURLOPT_POST.3
2024-03-07 00:54:32 -05:00

105 lines
4.0 KiB
Groff

.\" **************************************************************************
.\" * _ _ ____ _
.\" * Project ___| | | | _ \| |
.\" * / __| | | | |_) | |
.\" * | (__| |_| | _ <| |___
.\" * \___|\___/|_| \_\_____|
.\" *
.\" * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
.\" *
.\" * This software is licensed as described in the file COPYING, which
.\" * you should have received as part of this distribution. The terms
.\" * are also available at https://curl.se/docs/copyright.html.
.\" *
.\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell
.\" * copies of the Software, and permit persons to whom the Software is
.\" * furnished to do so, under the terms of the COPYING file.
.\" *
.\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
.\" * KIND, either express or implied.
.\" *
.\" * SPDX-License-Identifier: curl
.\" *
.\" **************************************************************************
.\"
.TH CURLOPT_POST 3 "17 Jun 2014" libcurl libcurl
.SH NAME
CURLOPT_POST \- make an HTTP POST
.SH SYNOPSIS
.nf
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_POST, long post);
.fi
.SH DESCRIPTION
A parameter set to 1 tells libcurl to do a regular HTTP post. This also makes
libcurl use a "Content-Type: application/x-www-form-urlencoded" header. This
is the most commonly used POST method.
Use one of \fICURLOPT_POSTFIELDS(3)\fP or \fICURLOPT_COPYPOSTFIELDS(3)\fP
options to specify what data to post and \fICURLOPT_POSTFIELDSIZE(3)\fP or
\fICURLOPT_POSTFIELDSIZE_LARGE(3)\fP to set the data size.
Optionally, you can provide data to POST using the
\fICURLOPT_READFUNCTION(3)\fP and \fICURLOPT_READDATA(3)\fP options but then
you must make sure to not set \fICURLOPT_POSTFIELDS(3)\fP to anything but
NULL. When providing data with a callback, you must transmit it using chunked
transfer-encoding or you must set the size of the data with the
\fICURLOPT_POSTFIELDSIZE(3)\fP or \fICURLOPT_POSTFIELDSIZE_LARGE(3)\fP
options. To enable chunked encoding, you simply pass in the appropriate
Transfer-Encoding header, see the post-callback.c example.
You can override the default POST Content-Type: header by setting your own
with \fICURLOPT_HTTPHEADER(3)\fP.
Using POST with HTTP 1.1 implies the use of a "Expect: 100-continue" header.
You can disable this header with \fICURLOPT_HTTPHEADER(3)\fP as usual.
If you use POST to an HTTP 1.1 server, you can send data without knowing the
size before starting the POST if you use chunked encoding. You enable this by
adding a header like "Transfer-Encoding: chunked" with
\fICURLOPT_HTTPHEADER(3)\fP. With HTTP 1.0 or without chunked transfer, you
must specify the size in the request. (Since 7.66.0, libcurl automatically
uses chunked encoding for POSTs if the size is unknown.)
When setting \fICURLOPT_POST(3)\fP to 1, libcurl automatically sets
\fICURLOPT_NOBODY(3)\fP and \fICURLOPT_HTTPGET(3)\fP to 0.
If you issue a POST request and then want to make a HEAD or GET using the same
reused handle, you must explicitly set the new request type using
\fICURLOPT_NOBODY(3)\fP or \fICURLOPT_HTTPGET(3)\fP or similar.
When setting \fICURLOPT_POST(3)\fP to 0, libcurl resets the request type to
the default to disable the POST. Typically that would mean it's reset to GET.
Instead you should set a new request type explicitly as described above.
.SH DEFAULT
0, disabled
.SH PROTOCOLS
HTTP
.SH EXAMPLE
.nf
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode res;
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/foo.bin");
curl_easy_setopt(curl, CURLOPT_POST, 1L);
/* set up the read callback with CURLOPT_READFUNCTION */
res = curl_easy_perform(curl);
curl_easy_cleanup(curl);
}
}
.fi
.SH AVAILABILITY
Along with HTTP
.SH RETURN VALUE
Returns CURLE_OK if HTTP is supported, and CURLE_UNKNOWN_OPTION if not.
.SH "SEE ALSO"
.BR CURLOPT_HTTPPOST (3),
.BR CURLOPT_POSTFIELDS (3),
.BR CURLOPT_PUT (3)