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Posted-Date: Wed, 8 Oct 1997 20:55:08 +0400
Subject: Re: udp and ifconfig alias
In-Reply-To: <Pine.BSF.3.96.971008090659.29502A-100000@darkstar.home> from "Charles Mott" at "Oct 8, 97 09:21:34 am"
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To: cmott@srv.net (Charles Mott)
Date: Wed, 8 Oct 1997 20:55:08 +0400 (MSD)
Cc: freebsd-hackers@FreeBSD.ORG
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> If I have multiple addresses on the same interface created with ifconfig
> alias, and a process is listening on udp *.7654, when a packet is returned
> after a call to recvfrom(), is it possible to tell which address it was
> sent to?  I have tried calling getsockname(), but my test code doesn't
> seem to be working.  And the more I think about it, getsockname() doesn't
> make sense for a connectionless protocol like UDP.

use recvmsg call, and IP_RECVDSTADDR option enabled (man 4 ip)

   Alex.

> 
> Charles Mott
> 
>