Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version VT1.00C 11/1/84; site vortex.UUCP Path: utzoo!watmath!clyde!burl!ulysses!petrus!bellcore!vortex!lauren From: lauren@vortex.UUCP (Lauren Weinstein) Newsgroups: net.mail.headers Subject: Re: From: and To: in UUCP land Message-ID: <742@vortex.UUCP> Date: Thu, 15-Aug-85 13:48:49 EDT Article-I.D.: vortex.742 Posted: Thu Aug 15 13:48:49 1985 Date-Received: Sun, 18-Aug-85 05:09:33 EDT References: <835@plus5.UUCP> Organization: Vortex Technology, Los Angeles Lines: 41 1) There is nothing wrong with putting @'s in the transport layer if you know that the site you're sending to can handle it properly. I keep tables with such knowledge, so that I can choose ! or @ routing as appropriate, based on my knowledge of the hosts. For example, ihnp4 can handle addresses like user@site.UUCP, so I can send them that way for domain-based mail that I'm sending to ihnp4 for non-local resolution. 2) @'s in the To: and From: lines are the ONLY way to maintain 822 compatibility with the outside world, and many smaller machines with limited software are starting to act as gateways and can't be expected to do @/! conversion. I see nothing wrong with @'s in the To:/From: lines so long as the From_ line is valid as a reply address. In the long run, the clue that a site SHOULD NOT futz with the From: line (except in certain gatewaying situations) is the presence of the @, except in certain obvious internet gatewaying situations. My own view is that due to various munging going on, it is important to support replies to both the From: and From_ line as necessary, and to send failed mail to the return addresses derived from internal spool files instead of header parsing. My own decision is to generate my From: lines in @ form, and to generate the To: lines in whatever form best resolves the message as posted by the user. I also allow replies to either the From_ line or the 822 lines. In the latter case, I follow the rules for Sender:/Reply-To:/etc. In the former case, I do a straight UUCP reply, but if an @ is present (on the From_ line) I give the !'s precedence (instead of the @, which has precendence on 822 lines). As a practical matter, even in our extremely mixed-up current environment, I find that I can successfully reply to 99+% of mail, through gateways and local nets, automatically, regardless of the smart or "dumb" hosts in the way. 3) As a general rule, I discourage the use of @'s in From_ lines, but when they occur I've found that my solution in (2) above works as a practical matter in the great majority of cases. --Lauren--