117 lines
4.6 KiB
Groff
117 lines
4.6 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_CONNECT_TO 3 "10 April 2016" libcurl libcurl
|
||
|
|
.SH NAME
|
||
|
|
CURLOPT_CONNECT_TO \- connect to a specific host and port instead of the URL's host and port
|
||
|
|
.SH SYNOPSIS
|
||
|
|
.nf
|
||
|
|
#include <curl/curl.h>
|
||
|
|
|
||
|
|
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_CONNECT_TO,
|
||
|
|
struct curl_slist *connect_to);
|
||
|
|
.fi
|
||
|
|
.SH DESCRIPTION
|
||
|
|
Pass a pointer to a linked list of strings with "connect to" information to
|
||
|
|
use for establishing network connections with this handle. The linked list
|
||
|
|
should be a fully valid list of \fBstruct curl_slist\fP structs properly
|
||
|
|
filled in. Use \fIcurl_slist_append(3)\fP to create the list and
|
||
|
|
\fIcurl_slist_free_all(3)\fP to clean up an entire list.
|
||
|
|
|
||
|
|
Each single string should be written using the format
|
||
|
|
HOST:PORT:CONNECT-TO-HOST:CONNECT-TO-PORT where HOST is the host of the
|
||
|
|
request, PORT is the port of the request, CONNECT-TO-HOST is the host name to
|
||
|
|
connect to, and CONNECT-TO-PORT is the port to connect to.
|
||
|
|
|
||
|
|
The first string that matches the request's host and port is used.
|
||
|
|
|
||
|
|
Dotted numerical IP addresses are supported for HOST and CONNECT-TO-HOST.
|
||
|
|
A numerical IPv6 address must be written within [brackets].
|
||
|
|
|
||
|
|
Any of the four values may be empty. When the HOST or PORT is empty, the host
|
||
|
|
or port always match (the request's host or port is ignored). When
|
||
|
|
CONNECT-TO-HOST or CONNECT-TO-PORT is empty, the "connect to" feature is
|
||
|
|
disabled for the host or port, and the request's host or port are used to
|
||
|
|
establish the network connection.
|
||
|
|
|
||
|
|
This option is suitable to direct the request at a specific server, e.g. at a
|
||
|
|
specific cluster node in a cluster of servers.
|
||
|
|
|
||
|
|
The "connect to" host and port are only used to establish the network
|
||
|
|
connection. They do NOT affect the host and port that are used for TLS/SSL
|
||
|
|
(e.g. SNI, certificate verification) or for the application protocols.
|
||
|
|
|
||
|
|
In contrast to \fICURLOPT_RESOLVE(3)\fP, the option
|
||
|
|
\fICURLOPT_CONNECT_TO(3)\fP does not pre-populate the DNS cache and therefore
|
||
|
|
it does not affect future transfers of other easy handles that have been added
|
||
|
|
to the same multi handle.
|
||
|
|
|
||
|
|
The "connect to" host and port are ignored if they are equal to the host and
|
||
|
|
the port in the request URL, because connecting to the host and the port in
|
||
|
|
the request URL is the default behavior.
|
||
|
|
|
||
|
|
If an HTTP proxy is used for a request having a special "connect to" host or
|
||
|
|
port, and the "connect to" host or port differs from the request's host and
|
||
|
|
port, the HTTP proxy is automatically switched to tunnel mode for this
|
||
|
|
specific request. This is necessary because it is not possible to connect to a
|
||
|
|
specific host or port in normal (non-tunnel) mode.
|
||
|
|
|
||
|
|
When this option is passed to \fIcurl_easy_setopt(3)\fP, libcurl does not copy
|
||
|
|
the list so you \fBmust\fP keep it around until you no longer use this
|
||
|
|
\fIhandle\fP for a transfer before you call \fIcurl_slist_free_all(3)\fP on
|
||
|
|
the list.
|
||
|
|
|
||
|
|
.SH DEFAULT
|
||
|
|
NULL
|
||
|
|
.SH PROTOCOLS
|
||
|
|
All
|
||
|
|
.SH EXAMPLE
|
||
|
|
.nf
|
||
|
|
CURL *curl;
|
||
|
|
struct curl_slist *connect_to = NULL;
|
||
|
|
connect_to = curl_slist_append(NULL, "example.com::server1.example.com:");
|
||
|
|
|
||
|
|
curl = curl_easy_init();
|
||
|
|
if(curl) {
|
||
|
|
curl_easy_setopt(curl, CURLOPT_CONNECT_TO, connect_to);
|
||
|
|
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
|
||
|
|
|
||
|
|
curl_easy_perform(curl);
|
||
|
|
|
||
|
|
/* always cleanup */
|
||
|
|
curl_easy_cleanup(curl);
|
||
|
|
}
|
||
|
|
|
||
|
|
curl_slist_free_all(connect_to);
|
||
|
|
.fi
|
||
|
|
.SH AVAILABILITY
|
||
|
|
Added in 7.49.0
|
||
|
|
.SH RETURN VALUE
|
||
|
|
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
|
||
|
|
.SH "SEE ALSO"
|
||
|
|
.BR CURLOPT_FOLLOWLOCATION (3),
|
||
|
|
.BR CURLOPT_HTTPPROXYTUNNEL (3),
|
||
|
|
.BR CURLOPT_RESOLVE (3),
|
||
|
|
.BR CURLOPT_URL (3)
|