I was wondering if UW Imap had the ability to report the system quota of the mail directory (i.e. the home directory) to users who were using the QUOTA extension.
At the current time, the answer is "no".
I know this is a pretty standard system call (I think)...so it shouldn't be too difficult to implement.
Unfortunately, this is not the case; there are at least three different implementations of UNIX quotas that I am aware of, each with different semantics. It would be fairly easy to assume that "all the world is Linux" and implement the QUOTA extension for Linux only; but imapd runs on many platforms besides Linux.
A different problem is that the QUOTA extension does more than report quotas; it also allows setting them. To make things more complicated, QUOTA allows the redistribution of quotas within a user's space (the concept of quota root).
Finally, IMAP QUOTA isn't defined in terms that directly map to UNIX quota; the suggested resources are STORAGE and MESSAGE, however on UNIX it is typically by disk block. There are also independent concepts of "grace" space which isn't represented in IMAP QUOTA.
None of this mean that "it can't be done"; however, to be useful and correct is quite a bit more complicated than the obvious simple implementation.
I know imapd can recognize when it's going to go over, but I don't know if it can be used, for example, with an imap mail client (I"m using SquirrelMail) that's asking what the quota is.
QUOTA is an optional extension; clients are expected to handle servers which do not offer an particular extension.
-- Mark --
http://staff.washington.edu/mrc Science does not emerge from voting, party politics, or public debate. Si vis pacem, para bellum.
