To: IETF working group on revision of mail standards <drums@cs.utk.edu>
Subject: Re: Fwd: Draft section_5.02.03
References: <v04210104b3dc2d0adeff@[130.237.157.164]>
From: Russ Allbery <rra@stanford.edu>
In-Reply-To: Jacob Palme's message of "Sun, 15 Aug 1999 10:41:30 +0200"
Date: 15 Aug 1999 04:57:18 -0700
Message-ID: <ylhfm19rz5.fsf@windlord.stanford.edu>
Lines: 27

Jacob Palme <jpalme@dsv.su.se> writes:

> I found the following message in the usenet-format mailing list.  It is
> rather unfortunate that the syntax for these headers is not the same in
> mail and news. But perhaps unavoidable?

There are two primary differences between [USEFOR] and [DRUMS] in handling
of those headers that are in common.  The first is that [USEFOR] permits
UTF-8 in the Subject header and in the non-address portions of the From
header, which [DRUMS] cannot do for backward-compatibility reasons.  The
second is that [USEFOR] deprecates or disallows certain sloppiness in
syntax for the Date and Message-ID headers that is allowed by [DRUMS]
(again largely for backward compatibility).  Parsing of these latter two
headers is a speed-critical aspect of a news implementation, while in mail
they're far less vital.  These headers have also been historically handled
more strictly by news software than by mail software (particularly
Message-ID, where there are virtually no restrictions in mail and
extremely strict and enforced restrictions in news in currently deployed
software).

This was the subject of past discussion between the two working groups and
the current state is the result of various compromises and efforts to
bring the standards closer.  I think it's unlikely they'll get much closer
than this given the differing goals of the two working groups.

-- 
Russ Allbery (rra@stanford.edu)         <URL:http://www.eyrie.org/~eagle/>