Expire Mail was written to expire old mail messages from users'
mailboxes, moving them to their own directories, and compressing them,
or throwing them away.

expire-all is a script which should be run every night, or every
saturday night: it looks at all the mailboxes trying to expire
messages from them.  It is currently configured to expire messages
older than 30 days, when they are more than 32 Kbytes long.

em-user is a script that is run by expire-all for every user whose
mailbox exists.  It invokes expmail to expire the messages.  As is, it
creates a new mail file whenever it expires some messages; removing
some '#' as indicated in the file, it may append the messages to old
expired files.

expmail is the program that does the hard job.  It looks for the
messages in a file, checks if they are older than a number of days,
and, if they are longer than a given size, runs a command specified.
This command is interpreted by /bin/sh.

getexpired is the program used to get the messages in expire-mail
system, and put them into gzipped files.  The user is sent a message
telling him some mail was expired, and a file is created in his home
directory, such as mail-yymmddhhmmss.gz, the string yymmddhhmmss is
the date+time when the command was run.  Note that this date does
*NOT* include the century, but, if someone does not read mail for a
whole century, it is probably not worth keeping anyway :-)

If you wish to remove the messages, instead of compressing them,
change em-user so that it tells expmail to run /bin/true instead of
getexpired.

I hope this is useful.

Alexandre Oliva  <oliva@dcc.unicamp.br>
