Please let me know if there was any attempt to make explicit locking of mailboxes an IMAP extension. I can see some advantages in having an explicit locking mechanism (and alas, some disadvantages too). Maybe you discussed already the implications of this idea, and you can point the threads dealing with it.
Consider a mailbox M having just one sensitive message, and two IMAP clients C1,C2 concurrently accessing M. The declared goal of C1 is to delete the sensitive message while C2 tries to postpone deletion as long as possible. Then the following situation may occur: C1: a1 store 1 +flags (\deleted) S : * fetch (flags (\deleted \seen)) S : a1 ok store completed C2: b1 store 1 -flags (\deleted) S : * fetch (flags (\seen)) S : b1 ok store completed C1: a2 expunge S : * fetch (flags (\seen)) S : a2 ok expunge completed C1: a3 store 1 +flags (\deleted) ... As one may see, C1 can not physically delete the message 1 if odds are against it. An explicit locking mechanism may help: C1: a1 lock_the_selected_mailbox S : a1 OK mailbox is yours ... C2: b1 store 1 -flags (\deleted) S : b1 NO mailbox is locked ... C1: a1001 unlock_the_selected_mailbox S : a1001 OK Marcel -- ----------------------------------------------------------------- For information about this mailing list, and its archives, see: http://www.washington.edu/imap/imap-list.html -----------------------------------------------------------------
