MBOX-Line: From mrc at Washington.EDU  Sat Feb 16 12:38:05 2008
To: imap-protocol@u.washington.edu
From: Mark Crispin <mrc@Washington.EDU>
Date: Fri Jun  8 12:34:41 2018
Subject: [Imap-protocol] header.fields fetching
In-Reply-To: <1203188859.4901.147.camel@hurina>
References: <1203188859.4901.147.camel@hurina>
Message-ID: <alpine.OSX.1.00.0802161232580.14588@pangtzu.panda.com>

On Sat, 16 Feb 2008, Timo Sirainen wrote:
> If I have a message:
> FROM: Foo
> to :Bar
> And BODY.PEEK[HEADER.FIELDS (from to)] returns:
> From: Foo
> To: Bar

There are two answers to this.

First, if what BODY.PEEK[HEADER.FIELDS ... ] returns is any different 
than what is returned in BODY[HEADER], then this is a violation of the 
IMAP immutability rule.  If the change is universal, so that it is as if 
the delivery process rewrote the headers before it got to IMAP, then there 
is no violation.

Second, it probably does not matter even though it is a violation.  It is 
difficult to imagine a client depending upon the immutability of data in 
partial header fetches, as typically this is used to augment ENVELOPE data 
for parsing and/or presentation to the end user.

Thus, IMHO, it's probably alright until such time as some client author 
complains; and such complaints are highly unlikely.  However, if there is 
a complaint, the client author would be in the right and the server in the 
wrong.

-- Mark --

http://panda.com/mrc
Democracy is two wolves and a sheep deciding what to eat for lunch.
Liberty is a well-armed sheep contesting the vote.

