Moving mails from one mailbox to another with formail
Use case: I’ve been using a specific folder for mails I’m considering to be spam, and mails in this folder is sent everyday to spamassassin’s sa-learn --spam for adding tokens to the bayes database.
I found out formail (available in the procmail package) will take an inbox as input, and will reformat mails, or allow to split/reformat/append mails before adding the mails to target mailbox.
Eg, the following command will show the 2nd mail of the mailbox:
$ cat ~/mail/inbox | formail +1 -1 -s
This command will print all first lines of each mail in the box, excepting the first one:
$ formail +1 -s head -n1 < /var/mail/$USER
Whole script, as a sample, to move all mails from Junk to Trash, sending then to sa-learn in between:
#!/bin/sh
JUNKBOX=/home/$USER/mail/Junk
TRASHBOX=/home/$USER/mail/Trash
/usr/bin/sa-learn --spam --mbox < ${JUNKBOX}
formail < ${JUNKBOX} >> ${TRASHBOX}
rm -f ${JUNKBOX}
touch ${JUNKBOX}