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From: Florian Weimer <fweimer@redhat.com>
To: "JOSHI, RAHUL via Libc-help" <libc-help@sourceware.org>
Cc: "JOSHI, RAHUL" <rahulj@hpe.com>
Subject: Re: Having TTL of resolved IP addresses in 'getaddrinfo' or 'getaddrinfo_a'
Date: Wed, 05 May 2021 10:39:35 +0200	[thread overview]
Message-ID: <87a6p9h8vs.fsf@oldenburg.str.redhat.com> (raw)
In-Reply-To: <CS1PR8401MB0502958E8F2E90F0AC840759C05B9@CS1PR8401MB0502.NAMPRD84.PROD.OUTLOOK.COM> (RAHUL via Libc-help JOSHI's message of "Mon, 3 May 2021 05:59:56 +0000")

* RAHUL via Libc-help JOSHI:

> Hi all, in current implementation of 'getaddrinfo' or 'getaddrinfo_a'
> , the TTL(expiry time) of resolved IP addresses isn't provided. Is
> there any alternate API in libc which will provide resolved IP
> addresses along with TTL??
>
> If no, what needs to be done to get the resolved addresses along with
> TTL??

We can't put the TTL directly into struct addrinfo because we shouldn't
change its size.  We'd have to add an accessor function and change the
way getaddrinfo allocates the result list.  Fortunately, there is a
freeaddrinfo function, so we can maintain a data structure on the side
that keeps track of TTLs, for use by the accessor function.

It's not super-hard, but also not exactly trivial, either.  I'm not
aware of anyone working on this feature, but it is requested from time
to time, so it would be a nice addition to glibc.

Thanks,
Florian


  parent reply	other threads:[~2021-05-05  8:39 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-03  5:59 JOSHI, RAHUL
2021-05-05  8:27 ` JOSHI, RAHUL
2021-05-05  8:33 ` JOSHI, RAHUL
2021-05-05  8:39 ` Florian Weimer [this message]
     [not found]   ` <CS1PR8401MB050236FE63C077687BC1C1D7C0599@CS1PR8401MB0502.NAMPRD84.PROD.OUTLOOK.COM>
2021-05-05  9:41     ` JOSHI, RAHUL
2021-05-05 12:27     ` JOSHI, RAHUL
2021-05-06  8:05     ` JOSHI, RAHUL
2021-05-06  9:20       ` Florian Weimer
2021-05-17 11:13 JOSHI, RAHUL
2021-05-17 11:16 ` Florian Weimer

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