Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!watmath!clyde!burl!ulysses!bellcore!decvax!decwrl!amdcad!lll-crg!seismo!mcvax!dpk From: dpk@mcvax.uucp (Doug Kingston) Newsgroups: net.mail Subject: Parsing mixed form addresses (! and @) Message-ID: <117@sering.mcvax.UUCP> Date: Sat, 1-Feb-86 08:20:39 EST Article-I.D.: sering.117 Posted: Sat Feb 1 08:20:39 1986 Date-Received: Mon, 3-Feb-86 05:34:34 EST References: <1942@peora.UUCP> <11500004@unido.UUCP> Reply-To: Doug Kingston Organization: CWI, Amsterdam Lines: 25 Summary: Context (source) is critical to correct parsing of ! vs @. Resent-Date: Sat, 1 Feb 86 13:20:41 MET Resent-From: news@mcvax.uucp Resent-To: rnews@haring.uucp Apparently-To: One of the big problems facing unix mail system now is the ambiguous nature of "mixed form addresses", e.g. x!y@z. As was recently mentioned by some others, the key to correctly parsing these addresses is to know the source. If you know the source (or more correctly its addressing format), then you can almost always determine the correct meaning of the address. UUCP addresses should be assumed to have ! precedence. Expect that when you generate them, and accept it when you receive them. Mail from 822 standards sources (PhoneNet, SMTP, Bitnet, ...) should be given %/@ precedence. This the basic policy being adopted in Europe. This was one of the major problems with Sendmail until recent enhanced config files were published. Sendmail would always use the same input parsing rules regardless of the source of the message. This is doomed to failure with mixed form addresses and more then one type of source. I am glad this is being changed. All ! or all @/% addresses are not a problem. They are unambiguous. -Doug- Doug Kingston Centrum voor Wiskunde en Informatica Kruislaan 413 1098 SJ Amsterdam, The Netherlands