[Imap-protocol] [noob] select & unseen?

Pete Maclean imap at maclean.com
Mon Nov 7 10:07:25 PST 2011

At 11:52 AM 11/7/2011, Mark Crispin wrote:

>On Mon, 7 Nov 2011, Bron Gondwana wrote:

>>RFC 3501 says " If this is missing, the

>> client can not make any assumptions about the first

>> unseen message in the mailbox, and needs to issue a

>> SEARCH command if it wants to find it. "

>>That means there is NO WAY for the server to communicate "there are no

>>unseen messages in this mailbox" in an unambiguous way.


>That means that if a client expects to know the position of the first

>unseen message at select time, instead of doing a SEARCH, it can not

>discriminate between the case of "there are no unseen messages" and

>"server does not support sending that information."

This is proving to be an interesting discussion for me because I have
a customer with a special sub-case of "there are no unseen
messages". Which is that they never have any unseen
messages. (Their message store is an archive. I don't know whether
they don't archive unseen messages or simply don't support a SEEN
flag. But that's not my business.) They expressed concern that
there is no way to indicate in a SELECT response that there are no
unseen messages. This might seem to necessitate an always
superfluous extra command-response for a client that insists on
knowing about unseen messages. However, if I understood one of
Mark's comments correctly, it seems likely that many clients will not
care about this information in isolation but only message flags in general.

I did suggest to this customer that an unsolicited STATUS response
could be sent of the form:

* STATUS Mailbox (Unseen 0)

but also expressed serious doubt that any client would pay
appropriate attention to this.

Does anyone else have any wise words to offer about this situation?

Pete Maclean

More information about the Imap-protocol mailing list