Mark Shaw asked,
| Once a month or so I'd like to process the default mail-
| box through procmail and delete all messages that con-
| tain the mailing-list header. All messages that do not
| contain that header would be deleted from the default
| mailbox and filed to a folder I'd define at the time I
| ran this task. I'd be left with an empty default mail-
| box.
The procmail(1) man page contains a shell routine for reprocessing mail
in an existing mailbox.
| I'd also like to run all my mailing-list mail folders
| through a recipe that would delete all messages older
| than X number of months.
That's not so easy. First one has to define age: since the message was
sent? Since the list re-sent it? Since it arrived? I'd recommend the
last.
Though I'm too pooped right now to write out the code, my suggestion is
to look at the From_ line or the topmost (youngest) Received: line, pull
the timestamp, and compare it to the current timestamp.