MBOX-Line: From mrc at CAC.Washington.EDU  Fri Nov 16 09:50:16 2007
To: imap-protocol@u.washington.edu
From: Mark Crispin <mrc@CAC.Washington.EDU>
Date: Fri Jun  8 12:34:40 2018
Subject: [Imap-protocol] FETCH/STORE on out-of-range sequence number
In-Reply-To: <2123708120.202451195235056495.JavaMail.root@dogfood.zimbra.com>
References: <2123708120.202451195235056495.JavaMail.root@dogfood.zimbra.com>
Message-ID: <alpine.OSX.0.99999.0711160945210.3800@pangtzu.panda.com>

On Fri, 16 Nov 2007, Dan Karp wrote:
> If there are 50 messages in the mailbox and a client requests
>   A001 FETCH 52 (FLAGS)
> then what are the acceptable server responses?

A001 BAD Invalid sequence number.

> I'm currently
> treating it as an example of RFC 2180 section 4.1.2 and returning
>   A001 NO Some of the requested messages no longer exist

It's a BAD because there is no way that a compliant client can reference 
an invalid sequence number.  The rules for EXPUNGE preclude it.

RFC 2180 section 4.1.2 was a terrible mistake and no server should ever do 
that.  4.1.3 is also pretty bad, and indicates a buggy server (or at least 
buggy mail store), but it is better than 4.1.2.  A server should do either 
4.1.1 or 4.1.4 instead.

Note as well that RFC 2180 is Informational.  The fact that an 
Informational RFC says something does not make it normative.

-- 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.

