Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!think.com!barmar From: barmar@think.com (Barry Margolin) Newsgroups: comp.mail.misc Subject: Re: Which headers may Sendmail re-write? Message-ID: <1990Dec14.174541.14252@Think.COM> Date: 14 Dec 90 17:45:41 GMT References: <2766B2E7.276@tct.uucp> <1990Dec14.064837.8996@Latour.Sandelman.OCUnix.On.Ca> Sender: news@Think.COM Organization: Thinking Machines Corporation, Cambridge MA, USA Lines: 35 In article <1990Dec14.064837.8996@Latour.Sandelman.OCUnix.On.Ca> fts1!latour!mcr@alfred.ccs.carleton.ca writes: > But, I/chip/tct-admin PUT chip@tct.UUCP in the From: > If I can't get a reply, THAT IS MY PROBLEM!!!!! While it may be your bug, it is the other person's problem. He wants to send you a reply, and has to hunt down a mail guru to figure out how to address it. He can't even contact you to ask what the correct address is, unless he knows how to reach you by some medium other than email. Here's a situation that you haven't addressed: what if the message is going to multiple recipients, using different mail protocols having different address conventions. For instance, To: foo!bar!baz!user1, user2@quux.dom.ain Further, assume the baz system is on the UUCP network, so only understands UUCP bang-paths, while quux.dom.ain is on the Internet and only understands RFC-822 addresses. The same "From" field can't be used when forwarding the message to both addresses, because one of them won't be able to reply to it. Furthermore, one of the To addresses needs to be munged, because most user agents provide the option of including all the original recipients as secondary recipients of the reply. Sendmail is an application-level protocol-translating gateway. There wouldn't be much controversy over an SMTP<->X.400 gateway munging headers; it's an obvious part of the job. Why do you expect less of a UUCP<->SMTP gateway? The header requirements and interpretation mechanisms of the two protocols are not identical, and it is the job of a gateway to transform a message coming in via one protocol into a valid message for the other protocol. -- Barry Margolin, Thinking Machines Corp. barmar@think.com {uunet,harvard}!think!barmar