.\" ************************************************************************** .\" * _ _ ____ _ .\" * Project ___| | | | _ \| | .\" * / __| | | | |_) | | .\" * | (__| |_| | _ <| |___ .\" * \___|\___/|_| \_\_____| .\" * .\" * Copyright (C) 1998 - 2019, Daniel Stenberg, , 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.haxx.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. .\" * .\" ************************************************************************** .\" .TH CURLOPT_POST 3 "17 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options" .SH NAME CURLOPT_POST \- request an HTTP POST .SH SYNOPSIS #include CURLcode curl_easy_setopt(CURL *handle, CURLOPT_POST, long post); .SH DESCRIPTION A parameter set to 1 tells libcurl to do a regular HTTP post. This will also make the library use a "Content-Type: application/x-www-form-urlencoded" header. (This is by far 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 will automatically use chunked encoding for POSTs if the size is unknown.) When setting \fICURLOPT_POST(3)\fP to 1, libcurl will automatically set \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 re-used handle, you must explicitly set the new request type using \fICURLOPT_NOBODY(3)\fP or \fICURLOPT_HTTPGET(3)\fP or similar. .SH DEFAULT 0, disabled .SH PROTOCOLS HTTP .SH EXAMPLE .nf CURL *curl = curl_easy_init(); if(curl) { 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 */ ret = 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_POSTFIELDS "(3), " CURLOPT_HTTPPOST "(3), "