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Path: utzoo!linus!decvax!ucbvax!ucdavis!lll-crg!seismo!munnari!kre
From: kre@munnari.OZ (Robert Elz)
Newsgroups: net.mail
Subject: Re: Precedence of operators
Message-ID: <979@munnari.OZ>
Date: Thu, 17-Oct-85 10:24:06 EDT
Article-I.D.: munnari.979
Posted: Thu Oct 17 10:24:06 1985
Date-Received: Sun, 20-Oct-85 07:38:07 EDT
References: <593@down.FUN> <10476@ucbvax.ARPA> <12317@Glacier.ARPA> <1737@peora.UUCP>
Organization: Comp Sci, Melbourne Uni, Australia
Lines: 49
Summary: Its no more possible to REQUIRE people to give ! and @ equal precedence than it is to REQUIRE people to give @ precedence over !

As best an I have been able to determine, no-one is advocating
that all sites should be required to give @ precedence in
rmail commands (uux message delivery).  A site that doesn't
know any @ mailers, just runs v7 (or Sys V) mail, and only
knows uucp is, and is always going to be, quite free to
just lop off the first "host!" and send mail to that host,
regardless of what is in the rest of the string.

But just as it is unreasonable, and impracticable to expect
sites to give '@' precedence at the uucp transport level,
its also impracticable to expect that every host in the world
is ever going to suddenly stop giving '@' precedence either.
It just won't happen.

What all that boils down to, is that unless you know what
every host on the path that you are using to route mail
will do with an '@' at the uucp transport level, then
its unsafe, unwise, and downright foolhardy to use one.

Its also NEVER necessary.  As long as there is ONE host
that will properly handle ...!host.dom!... addresses,
that's all that you need.  It may be expensive, and
unwelcome, but you could use uucp routing to get to
that one host, and then have it do the right things.
But we know that there is more than one such host
already, so you actually get a choice.  There is NO
requirement that every host that could possibly be
a gateway between the internet world and the uucp
world do this translation - if the one that happens
to be cheapest for you to mail to doesn't, then hard luck.
(You could always politely request that they change
things).

This "issue" that has been flamed about off and on
for ages now is really a non-issue.  '@' at the
uucp transport level is unsafe.  Without requiring
people to change their software, it will remain unsafe.
Sending mail with unsafe addresses is not a nice thing
to do, and is unnecessary.  Can we end this trivia please?

Robert Elz		seismo!munnari!kre	kre%munnari.oz@seismo.css.gov

ps: a reason that some sites like to give '@' precedence, in
any mail address, is that that means that an address at that
site *always* means the same thing.  Its not important how the
address happened to reach the site.  Given mail address X, this
is how we will treat it.  Personally, I think that is a laudable
aim, but I agree, this *is* a religious issue.  Arguing it is
pointless.