mirror of https://github.com/curl/curl.git synced 2025-02-05 14:30:10 +08:00

Daniel Stenberg b935fd4a07

docs: make each libcurl man specify protocol(s)

The mandatory header now has a mandatory list of protocols for which the
manpage is relevant.

Most man pages already has a "PROTOCOLS" section, but this introduces a
stricter way to specify the relevant protocols.

cd2nroff verifies that at least one protocol is mentioned (which can be
`*`).

This information is not used just yet, but A) the PROTOCOLS section can
now instead get generated and get a unified wording across all manpages
and B) this allows us to more reliably filter/search for protocol
specific manpages/options.

Closes #13166

2024-03-21 15:27:06 +01:00

1.6 KiB

Raw Blame History

c: Copyright (C) Daniel Stenberg, daniel@haxx.se, et al. SPDX-License-Identifier: curl Title: CURLOPT_HAPPY_EYEBALLS_TIMEOUT_MS Section: 3 Source: libcurl Protocol: - * See-also: - CURLOPT_CONNECTTIMEOUT_MS (3) - CURLOPT_LOW_SPEED_LIMIT (3) - CURLOPT_TIMEOUT (3)

NAME

CURLOPT_HAPPY_EYEBALLS_TIMEOUT_MS - head start for IPv6 for happy eyeballs

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HAPPY_EYEBALLS_TIMEOUT_MS,
                          long timeout);

DESCRIPTION

Happy eyeballs is an algorithm that attempts to connect to both IPv4 and IPv6 addresses for dual-stack hosts, preferring IPv6 first for timeout 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 timeout 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.

DEFAULT

CURL_HET_DEFAULT (currently defined as 200L)

PROTOCOLS

All except FILE

EXAMPLE

int main(void)
{
  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);
  }
}

AVAILABILITY

Added in 7.59.0

RETURN VALUE

Returns CURLE_OK

1.6 KiB Raw Blame History