mirror of
https://github.com/moparisthebest/curl
synced 2024-11-16 06:25:03 -05:00
102 lines
3.7 KiB
Groff
102 lines
3.7 KiB
Groff
.\" **************************************************************************
|
|
.\" * _ _ ____ _
|
|
.\" * Project ___| | | | _ \| |
|
|
.\" * / __| | | | |_) | |
|
|
.\" * | (__| |_| | _ <| |___
|
|
.\" * \___|\___/|_| \_\_____|
|
|
.\" *
|
|
.\" * Copyright (C) 1998 - 2019, 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.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_TRAILERFUNCTION 3 "14 Aug 2018" "libcurl 7.64.0" "curl_easy_setopt options"
|
|
.SH NAME
|
|
CURLOPT_TRAILERFUNCTION \- Set callback for sending trailing headers
|
|
.SH SYNOPSIS
|
|
#include <curl.h>
|
|
|
|
int curl_trailer_callback(struct curl_slist ** list, void *userdata);
|
|
|
|
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TRAILERFUNCTION, curl_trailer_callback *func);
|
|
.SH DESCRIPTION
|
|
Pass a pointer to a callback function.
|
|
|
|
This callback function will be called once right before sending the final
|
|
CR LF in an HTTP chunked transfer to fill a list of trailing headers to be
|
|
sent before finishing the HTTP transfer.
|
|
|
|
You can set the userdata argument with the CURLOPT_TRAILERDATA option.
|
|
|
|
The trailing headers included in the linked list must not be CRLF-terminated,
|
|
because libcurl will add the appropriate line termination characters after
|
|
each header item.
|
|
|
|
If you use curl_slist_append to add trailing headers to the curl_slist then
|
|
libcurl will duplicate the strings, and will free the curl_slist and the
|
|
duplicates once the trailers have been sent.
|
|
|
|
If one of the trailing headers is not formatted correctly
|
|
(i.e. HeaderName: headerdata) it will be ignored and an info message
|
|
will be emitted.
|
|
|
|
The return value can either be CURL_TRAILERFUNC_OK or CURL_TRAILERFUNC_ABORT
|
|
which would respectively instruct libcurl to either continue with sending the
|
|
trailers or to abort the request.
|
|
|
|
If you set this option to NULL, then the transfer proceeds as usual
|
|
without any interruptions.
|
|
.SH DEFAULT
|
|
NULL
|
|
.SH PROTOCOLS
|
|
HTTP
|
|
.SH EXAMPLE
|
|
#include <curl/curl.h>
|
|
|
|
static int trailer_cb(struct curl_slist **tr, void *data)
|
|
{
|
|
/* libcurl will free the list */
|
|
tr = curl_slist_append(*tr, "My-super-awesome-trailer: trailer-stuff");
|
|
return CURL_TRAILERFUNC_OK;
|
|
}
|
|
|
|
CURL *curl = curl_easy_init();
|
|
if(curl) {
|
|
/* Set the URL of the request */
|
|
curl_easy_setopt(curl, CURLOPT_URL, "http://example.com/");
|
|
/* Now set it as a put */
|
|
curl_easy_setopt(curl, CURLOPT_PUT, 1L);
|
|
|
|
/* Assuming we have a function that will return the data to be pushed
|
|
Let that function be read_cb */
|
|
curl_easy_setopt(curl, CURLOPT_READFUNCTION, read_cb);
|
|
|
|
struct curl_slist *headers = NULL;
|
|
headers = curl_slist_append(headers, "Trailer: My-super-awsome-trailer");
|
|
res = curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
|
|
|
|
/* Set the trailers filling callback */
|
|
curl_easy_setopt(curl, CURLOPT_TRAILERFUNCTION, trailer_cb);
|
|
|
|
/* Perform the request, res will get the return code */
|
|
res = curl_easy_perform(curl);
|
|
|
|
curl_easy_cleanup(curl);
|
|
|
|
curl_slist_free_all(headers);
|
|
}
|
|
.SH AVAILABILITY
|
|
This option was added in curl 7.64.0 and is present if HTTP support is enabled
|
|
.SH "SEE ALSO"
|
|
.BR CURLOPT_TRAILERDATA "(3), "
|