mirror of
https://github.com/moparisthebest/curl
synced 2024-11-14 05:25:06 -05:00
60 lines
2.4 KiB
Groff
60 lines
2.4 KiB
Groff
.\" **************************************************************************
|
|
.\" * _ _ ____ _
|
|
.\" * Project ___| | | | _ \| |
|
|
.\" * / __| | | | |_) | |
|
|
.\" * | (__| |_| | _ <| |___
|
|
.\" * \___|\___/|_| \_\_____|
|
|
.\" *
|
|
.\" * Copyright (C) 1998 - 2020, 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.
|
|
.\" *
|
|
.\" **************************************************************************
|
|
.\"
|
|
.TH CURLOPT_HAPPY_EYEBALLS_TIMEOUT_MS 3 "1 Feb 2018" "libcurl 7.59.0" "curl_easy_setopt options"
|
|
.SH NAME
|
|
CURLOPT_HAPPY_EYEBALLS_TIMEOUT_MS \- head start for ipv6 for happy eyeballs
|
|
.SH SYNOPSIS
|
|
#include <curl/curl.h>
|
|
|
|
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HAPPY_EYEBALLS_TIMEOUT_MS, long timeout);
|
|
.SH DESCRIPTION
|
|
Happy eyeballs is an algorithm that attempts to connect to both IPv4 and IPv6
|
|
addresses for dual-stack hosts, preferring IPv6 first for \fItimeout\fP
|
|
milliseconds. If the IPv6 address cannot be connected to within that time then
|
|
a connection attempt is made to the IPv4 address in parallel. The first
|
|
connection to be established is the one that is used.
|
|
|
|
The range of suggested useful values for \fItimeout\fP is limited. Happy
|
|
Eyeballs RFC 6555 says "It is RECOMMENDED that connection attempts be paced
|
|
150-250 ms apart to balance human factors against network load." libcurl
|
|
currently defaults to 200 ms. Firefox and Chrome currently default to 300 ms.
|
|
.SH DEFAULT
|
|
CURL_HET_DEFAULT (currently defined as 200L)
|
|
.SH EXAMPLE
|
|
.nf
|
|
CURL *curl = curl_easy_init();
|
|
if(curl) {
|
|
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
|
|
curl_easy_setopt(curl, CURLOPT_HAPPY_EYEBALLS_TIMEOUT_MS, 300L);
|
|
|
|
curl_easy_perform(curl);
|
|
|
|
/* always cleanup */
|
|
curl_easy_cleanup(curl);
|
|
}
|
|
.fi
|
|
.SH AVAILABILITY
|
|
Added in 7.59.0
|
|
.SH RETURN VALUE
|
|
Returns CURLE_OK
|