Re: Serious problems with multiple connections working with the same mailbox

On Fri, 23 Sep 2005, [ISO-8859-1] Jerry Lundstr=F6m wrote:
>1: TAG NOOP
>1: * 611 EXISTS
>1: TAG OK NOOP completed
>1: TAG FETCH 611 FLAGS
>1: * 611 FETCH (FLAGS ())
>1: TAG OK FETCH completed
>2: TAG FETCH 611 FLAGS
>2: * 611 EXISTS
>2: TAG OK FETCH completed

This is perfectly normal behavior. The server for connection 2 does not
know about message 611, so it returns no flags to the request (because 611
is outside the known message set). It does, however, report a new message
arrival as part of the pending updates. Only after receiving the EXISTS
response can the client make assumptions about the result of FETCH on that
message.

So the client on connection 2 is misbehaving, regardless of whether
connection 1 is held by the same client. Each connection has a separate
state in IMAP. The proper client behavior is to first issue the NOOP, then
the FETCH. It cannot and must not assume that 611 exists on all
connections just because connection 1 reported it. :-) This is also why
EXPUNGE responses are not allowed as part of a pending update.

If I have understood the problem correctly, the fix should be reverted and
a bug report should be filed to the relevant client authors. :-)

Andy

--
Andreas Aardal Hanssen   | http://www.andreas.hanssen.name/gpg
Author of Binc IMAP      |  "It is better not to do something
http://www.bincimap.org/ |        than to do it poorly."