1--- 2c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. 3SPDX-License-Identifier: curl 4Title: CURLOPT_PIPEWAIT 5Section: 3 6Source: libcurl 7See-also: 8 - CURLMOPT_MAX_HOST_CONNECTIONS (3) 9 - CURLMOPT_PIPELINING (3) 10 - CURLOPT_FORBID_REUSE (3) 11 - CURLOPT_FRESH_CONNECT (3) 12Protocol: 13 - HTTP 14Added-in: 7.43.0 15--- 16 17# NAME 18 19CURLOPT_PIPEWAIT - wait for multiplexing 20 21# SYNOPSIS 22 23~~~c 24#include <curl/curl.h> 25 26CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PIPEWAIT, long wait); 27~~~ 28 29# DESCRIPTION 30 31Set *wait* to 1L to tell libcurl to prefer to wait for a connection to 32confirm or deny that it can do multiplexing before continuing. 33 34When about to perform a new transfer that allows multiplexing, libcurl checks 35for existing connections to use. If no such connection exists it immediately 36continues and creates a fresh new connection to use. 37 38By setting this option to 1 - and having CURLMOPT_PIPELINING(3) enabled 39for the multi handle this transfer is associated with - libcurl instead waits 40for the connection to reveal if it is possible to multiplex on before it 41continues. This enables libcurl to much better keep the number of connections 42to a minimum when using multiplexing protocols. 43 44With this option set, libcurl prefers to wait and reuse an existing connection 45for multiplexing rather than the opposite: prefer to open a new connection 46rather than waiting. 47 48The waiting time is as long as it takes for the connection to get up and for 49libcurl to get the necessary response back that informs it about its protocol 50and support level. 51 52# DEFAULT 53 540 (off) 55 56# %PROTOCOLS% 57 58# EXAMPLE 59 60~~~c 61int main(void) 62{ 63 CURL *curl = curl_easy_init(); 64 if(curl) { 65 curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/"); 66 curl_easy_setopt(curl, CURLOPT_PIPEWAIT, 1L); 67 68 /* now add this easy handle to the multi handle */ 69 } 70} 71~~~ 72 73# %AVAILABILITY% 74 75# RETURN VALUE 76 77Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. 78
