Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!ora!minya!jc
From: jc@minya.UUCP (John Chambers)
Newsgroups: comp.mail.misc
Subject: Is '@' ever needed?
Keywords: '%'
Message-ID: <797@minya.UUCP>
Date: 17 Jun 91 23:31:51 GMT
Lines: 47

This may sound silly, but I  recently  realized,  and  testing  on  an
assortment  of machines has so far verified, that there seems to be no
reason to ever use '@' in a mail address.   If  you  always  use  '%',
mailers  that  I've tested all seem to accept it and convert it to '@'
when necessary.  I'm wondering if this really works everywhere.

This isn't entirely trivial. I've had some trouble at times explaining
to  novice  users  what  the  rules for email addresses are.  They are
mostly unbelieving at the complexity of it all.  ("Why can't they just
...?") I've been trying to find simple ways of explaining it.

The uucp and decnet syntaxes are pretty easy to explain. They are just
a  list  of  machine  names  followed  by a user name, and this can be
explained in seconds.  The only thing wierd  is  that  I  find  myself
explaining  "Well,  of course, no self-respecting hacker (oops, I mean
professional software engineer ;-) would ever  consider  something  so
obvious  as  using a comma as a list separator, so you have to use '!'
or '::' or something equally silly, but really it's  just  a  list  of
machines that know how to talk to each other, and a userid at the end.

But then I come to the internet notation, and people look at me really
strangely  when  I  try to explain why you write a list backwards, use
'%' for all but the last separator, and a '@' for the very  last  one.
(About all  I  can  say is that it is a good thing to think about when
someone is trying to tell you how well-designed it all is. :-)

It seems I can (so far) get  away  with  saying  to  use  '%'  as  the
internet  list separator, and if you see '@', it is equivalent to '%'.
Of course, I should also give an example explaining just why it  is  a
bad idea to mix '%' with '!' or '::', but that's a whole different bag
of worms that we won't go into until the next lesson.

So.  Are there any mailers lurking about for  which  '@'  is  actually
necessary?   Can  you  really always use '%' instead?  I'm not talking
about internal mail-system stuff, of course.  I'm also not looking for
any treatises on how '@' is the original and '%' is an add-on; history
is very interesting,  but  it's  not  the  current  point.   I'm  just
interested  in  what the poor suckers trying to get it to work have to
type to the computer.  Maybe you should try %-only addresses  on  your
mailer and report if it chokes. If we turn up any, maybe we can harass
the vendors to get them upgraded...

-- 
All opinions Copyright (c) 1991 by John Chambers.  Inquire for licensing at:
Home: 1-617-484-6393 
Work: 1-508-486-5475
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