From owner-freebsd-net@FreeBSD.ORG  Mon Jan 19 03:07:31 2004
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To: net@freebsd.org
From: Poul-Henning Kamp <phk@phk.freebsd.dk>
Date: Mon, 19 Jan 2004 12:07:25 +0100
Message-ID: <91262.1074510445@critter.freebsd.dk>
Subject: Multihomed UDP server
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Simple question:

Very simple UDP server daemon.

Many clients (connect(2)'ing a socket for each is not an option)

Multihomed machine.

What's the simple trick to replying with the same source-IP as the
client used as destination-IP ?

Notice I said "simple", monitoring the routetable or polling the
interface configuration does not count as "simple".

It seems to me that if there is no simple way to do this, it's
about time we added it...

As I see it, we need recvfromto() and sendtofrom().

Any takers ?

Poul-Henning

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.