cURL / Mailing Lists / curl-library / Single Mail

curl-library

Re: when domain lookup result has ipv6 and ipv4

From: Dan Fandrich <dan_at_coneharvesters.com>
Date: Thu, 2 Jul 2015 08:16:50 +0200

On Thu, Jul 02, 2015 at 09:59:05AM +0800, Vincent Chen wrote:
> I'm developing a HTTP client with multi interface and have some questions when
> domain name look up has both IPv6 & IPv4 address
>
> [Question1]
> I implement the opensocket call back to create socket by myself and monitor
> socket event.
>
> and found the callback will be called twice.
>
> First callback is for IPv6 and the second callback is for IPv4.

This behaviour is called "Happy Eyeballs" and is covered by RFC6555.

>>> Dan
-------------------------------------------------------------------
List admin: http://cool.haxx.se/list/listinfo/curl-library
Etiquette: http://curl.haxx.se/mail/etiquette.html
Received on 2015-07-02