Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!rochester!uhura.cc.rochester.edu!msir
From: msir@uhura.cc.rochester.edu (Mark Sirota)
Newsgroups: comp.mail.sendmail
Subject: Re: localhost!user
Message-ID: <828@ur-cc.UUCP>
Date: 8 Feb 89 22:40:26 GMT
References: <1377@ncar.ucar.edu>
Reply-To: msir@cc.rochester.edu (Mark Sirota)
Organization: Univ. of Rochester, Computing Center
Lines: 33

In article <1377@ncar.ucar.edu> woods@ncar.UCAR.EDU (Greg Woods) writes:

> I used to have a list of all our local hosts within the sendmail.cf file. I
> have recently redone the cf file to eliminate this, as it was becoming a
> real hassle to keep this list up to date, with the proliferation of
> single-user hosts (like Sun workstations) around here. So, I changed the
> cf file to simply assume that all unqualified host references are local.

Good move, not keeping any lists in the cf.  However, why do you care if a
host is local or not?  I simply canonicalize each name in S3, and deliver
any local mail via TCP just as I would deliver foreign mail.

Is there anything wrong with doing it that way?  What reason is there for
differentiating between local and foreign mail?

> Everything works, with one exception: there doesn't seem to be any way to
> look at an address of the form host!user and determine whether or not the
> host is local. ... Ideally I'd like to use the name server to do this, but
> the exact way to make it work eludes me. I am trying things like
> 
> $-!$-	$[$1.$]!$2
> 
> and then checking to see if the trailing period disappears indicating a
> match.

Why not just canonicalize the name (what you've got without the trailing
dot) and then check to see if the address is now "$+.$D!$+"?  Will that do
what you're looking for?
-- 
Mark Sirota - University of Rochester, Rochester, NY
 Internet: msir@cc.rochester.edu
 Bitnet:   msir_ss@uordbv.bitnet
 UUCP:     ...!rochester!ur-cc!msir