Procmail Guide, Meaning , Facts, Information and Description
Procmail is a mail delivery agent (MDA) or mail filter, a program to process incoming emails on a computer, widely used on Unix systems. It is typically invoked from an MTA like Sendmail.Common operations carried out with procmail include filtering and sorting of emails into different folders according to keywords in from, to, subject or text of the mail, but more sophisticated operations are also possible.
A common practice is to let Procmail call an external spam filter program, such as SpamAssassin.