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From: Terry Lambert <terry@lambert.org>
Message-Id: <199708271716.KAA05689@phaeton.artisoft.com>
Subject: Re: UDP "to" address?
To: louie@TransSys.COM (Louis A. Mamakos)
Date: Wed, 27 Aug 1997 10:16:12 -0700 (MST)
Cc: aledm@routers.co.uk, hackers@FreeBSD.ORG
In-Reply-To: <199708261352.JAA04942@whizzo.TransSys.COM> from "Louis A. Mamakos" at Aug 26, 97 09:52:07 am
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> Typically, a portable approach to doing this is to create a socket
> per interface address and bind it.  Then you look at which fd the
> packet was received on to determine the destination address.
> 
> Look at named and xntpd to get a sense of this.  In fact, you can
> probably steal a lot of this code and apply it directly.  
> 
> There also seems to be a socket option you can set which returns the
> destination address in the "control information" field specified
> with recvmsg(2).   I noticed the code for this in ip_input.c.

This is an issue for the NFS UDP code, actually.  If you get a general
answer, it'd be helpful.  I thin recvmsg() is probably the way to go.


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.