[Dovecot] LSUB and subscribed folders

[Michael M Slusarz]

Quoting Peer Heinlein <p.heinlein at heinlein-support.de>:

> Using the LSUB-command, which should only list subscribed folders I can see
> some more shared folders. AFAIK the output of LSUB must be always less then
> LIST:

No, it is exactly the opposite - LSUB can potentially list MORE  
mailboxes than exist on the server.  LSUB only provides the list of  
mailboxes that have been marked as subscribed.

It is quite possible to mark a mailbox as subscribed and then delete  
it, in which case LSUB must continue to report that mailbox.  See RFC  
3501 [6.3.9]:

       The server MUST NOT unilaterally remove an existing mailbox name
       from the subscription list even if a mailbox by that name no
       longer exists.


michael