Re: [Exim] Expiring mails in appendfile.c

> This is much better done as a separate process, rather in the MTA itself.
> Something that is run, once a day or on a predetermined schedule.

If Exim does it, it is done when the directory pages are already cached.

A daily run through all mailboxes would be very expensive, in particular
because it had to evaluate the filter for all folders of all users to
determine their preferences, even if there would be nothing to expire.
Its advantage would be to wipe out things even if no new mail came in.
In summary, it would save disk space on the cost of disk transactions.
These days space is cheap, but transactions are expensive, and the ratio
gets worse each year.

> I don't think many would use it inside the MTA.

Depends on your definition of "use". A few million customers would,
if I offered it, pretty much like Sieve filters. ;-)

Michael