Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!brl-adm!adm!GUMBY@mit-ai.arpa From: GUMBY@mit-ai.arpa (David Vinayak Wallace) Newsgroups: comp.mail.headers Subject: Replying to Sender or (gasp) Return-path Message-ID: <878@brl-adm.ARPA> Date: Tue, 18-Nov-86 00:30:42 EST Article-I.D.: brl-adm.878 Posted: Tue Nov 18 00:30:42 1986 Date-Received: Tue, 18-Nov-86 03:49:38 EST Sender: news@brl-adm.ARPA Lines: 22 Date: Mon, 17 Nov 86 19:48:06 -0800 From: Marshall Rose there is a difference between working correctly and working. Working correctly is to ignore sender and return-path. However this is not often working...there is neither perfection nor diligence in the Internet. It is better to know that you can fall back on sender and/or return path in case you have to (when working on a poorly constructed message), than to just say "you can't reply to that". There's a difference between DWIM and incorrectness. Your mail handler may reasonably complain "I can't reply to that" and ask the human for help; it can't reasonably figure out which of From, Sender or Return-Path might interest the user (for instance, if I want to send a message to someone who will fix it up I might send a message to the Return-Path, whereas in a legitimate reply I might be able to construct a valid destination address). For purposes of replying there isn't much difference between Return-Path, Sender, and Subject. They all have inappropriate semantics. The machine shouldn't fake out naive users by using random information.