Procmail EXITCODE

Random Info #1
Monday, November 27, 2000

Nathan sent me this wonderful procmail tip that will deliver mail as usual, then bounce it back to the sender as if it was never delivered.

:0 c
* ^From.*(evilguy@|eguy@)
mail/eguy

:0
* ^From.*(evilguy@|eguy@)
{ EXITCODE=67
HOST=
}

The first recipe saves the email to mail/eguy. The "c" in the first line prevents delivery from being signalled, so it will continue on to the next recipe.

The second recipe bounces the mail.

Exitecode 67 is for Sendmail; other MTAs may use different codes to signal a failed delivery. For example, Qmail uses exitcode 100. Do a Google search if you're unsure about your MTA's exitcodes.