1
0
mirror of https://github.com/moparisthebest/curl synced 2024-11-05 09:05:04 -05:00
curl/docs/cmdline-opts/happy-eyeballs-timeout-ms.d
Anders Bakken 2427d94c6d url: Add option CURLOPT_HAPPY_EYEBALLS_TIMEOUT
- Add new option CURLOPT_HAPPY_EYEBALLS_TIMEOUT to set libcurl's happy
  eyeball timeout value.

- Add new optval macro CURL_HET_DEFAULT to represent the default happy
  eyeballs timeout value (currently 200 ms).

- Add new tool option --happy-eyeballs-timeout-ms to expose
  CURLOPT_HAPPY_EYEBALLS_TIMEOUT. The -ms suffix is used because the
  other -timeout options in the tool expect seconds not milliseconds.

Closes https://github.com/curl/curl/pull/2260
2018-02-20 17:51:43 -05:00

18 lines
841 B
D

Long: happy-eyeballs-timeout-ms
Arg: <milliseconds>
Help: How long to wait in milliseconds for IPv6 before trying IPv4
Added: 7.59.0
---
Happy eyeballs is an algorithm that attempts to connect to both IPv4 and IPv6
addresses for dual-stack hosts, preferring IPv6 first for the number of
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 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.
If this option is used several times, the last one will be used.