Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!ncar!woods
From: woods@ncar.ucar.edu (Greg Woods)
Newsgroups: comp.mail.uucp
Subject: Re: Sendmail and pathalias
Message-ID: <633@ncar.ucar.edu>
Date: 25 Aug 88 17:59:54 GMT
References: <4540@saturn.ucsc.edu> <23668@uunet.UU.NET> <2390@rtech.rtech.com> <75@volition.dec.com> <13206@mimsy.UUCP>
Reply-To: woods@handies.UCAR.EDU (Greg Woods)
Organization: Scientific Computing Division/NCAR, Boulder CO
Lines: 32

In article <13206@mimsy.UUCP> chris@mimsy.UUCP (Chris Torek) writes:
>What you do is
>have sendmail `deliver' everything to a program that does the routing,
>then hands the message back to sendmail for *real* delivery. 

  That's what I do; the "program" in question is "smail", with a modification
that causes it to recognize when the first hop in the generated route is
really an Internet link, in which case it hands it back to sendmail for
delivery by SMTP. All you have to do is make sure your sendmail.cf file
will recognize those paths as Internet links, by having rules like

Cslist-of-fake-uucp-links-that-are-really-Internet
$=s!$+	$2@$[$1.$]  # yes, I know this is oversimplified

Then you need appropriate CNAME records in your name server for these
"fake uucp" hosts, e.g.

GATECH.	IN	CNAME	GATECH.EDU.	

So it works like this:

1) address comes into sendmail of the form user@host.podunk.edu

2) If podunk.edu is in list of known Internet domains, deliver by SMTP

3) Hand off to smail

4) If generated route is through a real uucp site,  queue via uux

5) Hand generated bang path back to sendmail, which hopefully will NOT
   pass it back to smail again and start an infinite loop :-)

--Greg