[vox-tech] How to apply procmail filters to existing mailbox?

[GNU Linux]

On Thu, Sep 26, 2002 at 03:27:37PM -0700, Peter Jay Salzman wrote:
> harry,
> 
> why this doesn't create an infinite loop when it processes an email that
> doesn't match any rules in .procmailrc?

Depending on the procmail_rc file you could potentially have duplicates.

> don't these emails go right back into /var/mail/graham?

Not necessarily. (but by default yes)

> > cat /var/mail/graham | procmail -m procmail_rc_file 

In the example above I filtered all the incoming mail waiting in
/var/mail/graham through procmail. I did NOT use my regular procmail_rc
file, but an altered rc file that moved mail into folders depending on
mailing list rules, spam rules, etc. Mail that didn't match anything was
put in a different file -- thus preventing getting a duplicate.

> > Be careful of your directories and file names that are in the
> > procmail_rc_file. You could get email placed where you don't want it.

Yup.

So, potentially you could get mail in funky places if your rc file is
not altered appropriately and possibly duplicates in /var/mail/graham. I
don't believe you will get an endless loop though.