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Path: utzoo!henry
From: henry@utzoo.UUCP (Henry Spencer)
Newsgroups: net.mail,net.mail.headers
Subject: Re: Do you rewrite "From:" lines?
Message-ID: <7251@utzoo.UUCP>
Date: Mon, 20-Oct-86 15:17:41 EDT
Article-I.D.: utzoo.7251
Posted: Mon Oct 20 15:17:41 1986
Date-Received: Mon, 20-Oct-86 15:17:41 EDT
References: <358@tc-jeff.fluke.UUCP> <736@ncc.UUCP> <112@cpro.UUCP> <1101@plus5.UUCP> <7212@utzoo.UUCP>, <555@rnRe: Do you rewrite "From:" lMon, 20-Oct-86 15:17:41 EDT
Organization: U of Toronto Zoology
Lines: 31

> >Um, not correct:  dumb V7 mailers have no concept of mail headers at all,
> >much less any specific notions about the "To:" line.  Believe me; we run
> >one.  (And as a result we're the only major network hub in this part of
> >the world whose mailer is 100% predictable and 100% reliable.)
> 
> What happens when you get mail that is misaddressed (wrong host, unknown
> login name) ? Do you predictably and reliably drop it on the floor ?

No, we predictably and reliably [we fixed the locking system] forward it
to the postmaster [me] for appropriate action.  There is no completely
satisfactory way of dealing with it automatically.  Believe me, there isn't.
Even returning it to the sender is an arbitrarily difficult job, because
it implies determining the return address from the headers.  I think I can
safely say that I am smarter than any automated header parser, and *I*
sometimes have considerable trouble sorting out the correct return address
(no points for getting it wrong, guys, or believing headers that are lying).
Sometimes, whether it goes on to its destination or back to its sender
is a matter of whose address is easier to determine!

> How can it be 100% when its based on uucp as its transport ?

The mailer is not based on uucp.  The mail system as a whole is.  The
unreliability of one part of the system (uucp) is not an excuse for
unreliability of other parts.

>	A crashed machine is 100% predictable and reliable, too.

Then it's a considerable improvement on sendmail!
-- 
				Henry Spencer @ U of Toronto Zoology
				{allegra,ihnp4,decvax,pyramid}!utzoo!henry