84 lines
2.0 KiB
Markdown
84 lines
2.0 KiB
Markdown
|
---
|
||
|
|
c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
|
||
|
|
SPDX-License-Identifier: curl
|
||
|
|
Title: CURLOPT_CONNECT_ONLY
|
||
|
|
Section: 3
|
||
|
|
Source: libcurl
|
||
|
|
See-also:
|
||
|
|
- CURLOPT_HTTPPROXYTUNNEL (3)
|
||
|
|
- CURLOPT_VERBOSE (3)
|
||
|
|
- curl_easy_recv (3)
|
||
|
|
- curl_easy_send (3)
|
||
|
|
---
|
||
|
|
|
||
|
|
# NAME
|
||
|
|
|
||
|
|
CURLOPT_CONNECT_ONLY - stop when connected to target server
|
||
|
|
|
||
|
|
# SYNOPSIS
|
||
|
|
|
||
|
|
~~~c
|
||
|
|
#include <curl/curl.h>
|
||
|
|
|
||
|
|
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_CONNECT_ONLY, long only);
|
||
|
|
~~~
|
||
|
|
|
||
|
|
# DESCRIPTION
|
||
|
|
|
||
|
|
Pass a long. If the parameter equals 1, it tells the library to perform all
|
||
|
|
the required proxy authentication and connection setup, but no data transfer,
|
||
|
|
and then return.
|
||
|
|
|
||
|
|
The option can be used to simply test a connection to a server, but is more
|
||
|
|
useful when used with the CURLINFO_ACTIVESOCKET(3) option to
|
||
|
|
curl_easy_getinfo(3) as the library can set up the connection and then
|
||
|
|
the application can obtain the most recently used socket for special data
|
||
|
|
transfers.
|
||
|
|
|
||
|
|
Since 7.86.0, this option can be set to '2' and if HTTP or WebSocket are used,
|
||
|
|
libcurl performs the request and reads all response headers before handing
|
||
|
|
over control to the application.
|
||
|
|
|
||
|
|
Transfers marked connect only do not reuse any existing connections and
|
||
|
|
connections marked connect only are not allowed to get reused.
|
||
|
|
|
||
|
|
If the connect only transfer is done using the multi interface, the particular
|
||
|
|
easy handle must remain added to the multi handle for as long as the
|
||
|
|
application wants to use it. Once it has been removed with
|
||
|
|
curl_multi_remove_handle(3), curl_easy_send(3) and
|
||
|
|
curl_easy_recv(3) do not function.
|
||
|
|
|
||
|
|
# DEFAULT
|
||
|
|
|
||
|
|
0
|
||
|
|
|
||
|
|
# PROTOCOLS
|
||
|
|
|
||
|
|
HTTP, SMTP, POP3 and IMAP. For WS and WSS starting in 7.86.0.
|
||
|
|
|
||
|
|
# EXAMPLE
|
||
|
|
|
||
|
|
~~~c
|
||
|
|
int main(void)
|
||
|
|
{
|
||
|
|
CURL *curl = curl_easy_init();
|
||
|
|
if(curl) {
|
||
|
|
CURLcode ret;
|
||
|
|
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
|
||
|
|
curl_easy_setopt(curl, CURLOPT_CONNECT_ONLY, 1L);
|
||
|
|
ret = curl_easy_perform(curl);
|
||
|
|
if(ret == CURLE_OK) {
|
||
|
|
/* only connected! */
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
~~~
|
||
|
|
|
||
|
|
# AVAILABILITY
|
||
|
|
|
||
|
|
Added in 7.15.2
|
||
|
|
|
||
|
|
# RETURN VALUE
|
||
|
|
|
||
|
|
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
|