.\" ************************************************************************** .\" * _ _ ____ _ .\" * Project ___| | | | _ \| | .\" * / __| | | | |_) | | .\" * | (__| |_| | _ <| |___ .\" * \___|\___/|_| \_\_____| .\" * .\" * Copyright (C) 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.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_ONLY 3 "August 22, 2023" "ibcurl 8.3.0" libcurl .SH NAME CURLOPT_CONNECT_ONLY \- stop when connected to target server .SH SYNOPSIS .nf #include CURLcode curl_easy_setopt(CURL *handle, CURLOPT_CONNECT_ONLY, long only); .fi .SH 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 \fICURLINFO_ACTIVESOCKET(3)\fP option to \fIcurl_easy_getinfo(3)\fP 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 \fIcurl_multi_remove_handle(3)\fP, \fIcurl_easy_send(3)\fP and \fIcurl_easy_recv(3)\fP do not function. .SH DEFAULT 0 .SH PROTOCOLS HTTP, SMTP, POP3 and IMAP. For WS and WSS starting in 7.86.0. .SH EXAMPLE .nf 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! */ } } .fi .SH AVAILABILITY Added in 7.15.2 .SH RETURN VALUE Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. .SH "SEE ALSO" .BR CURLOPT_VERBOSE "(3), " CURLOPT_HTTPPROXYTUNNEL "(3), " .BR curl_easy_recv "(3), " curl_easy_send "(3) "