## Using procmail 

***Contributed by Marc Silver. ***

The ***procmail*** utility is an incredibly powerful application used to filter incoming mail. It allows users to define ***rules*** which can be matched to incoming mails to perform specific functions or to reroute mail to alternative mailboxes and/or email addresses.  **procmail**  can be installed using the [mail/procmail](http://pkgsrc.se/mail/procmail) port. Once installed, it can be directly integrated into most MTAs; consult your MTA documentation for more information. Alternatively,  **procmail**  can be integrated by adding the following line to a `.forward` in the home directory of the user utilizing  **procmail**  features:

    
    "|exec /usr/local/bin/procmail || exit 75"


The following section will display some basic  **procmail**  rules, as well as brief descriptions on what they do. These rules, and others must be inserted into a `.procmailrc` file, which must reside in the user's home directory.

Forward all mail from `user@example.com` to an external address of `goodmail@example2.com`:

    
    :0
    
* ^From.*user@example.com
    ! goodmail@example2.com


Forward all mails shorter than 1000 bytes to an external address of `goodmail@example2.com`:

    
    :0
    
* < 1000
    ! goodmail@example2.com


Send all mail sent to `alternate@example.com` into a mailbox called `alternate`:

    
    :0
    
* ^TOalternate@example.com
    alternate


Send all mail with a subject of ***Spam*** to `/dev/null`:

    
    :0
    ^Subject:.*Spam
    /dev/null


A useful recipe that parses incoming `dragonflybsd.org` mailing lists and places each list in its own mailbox:

    
    :0
    
* ^List-Post: &lt;mailto:\/[^@]+
    {
    	LISTNAME=${MATCH}
    	:0
    
* LISTNAME??^\/[^-]+
    	DragonFly-${MATCH}
    }




CategoryHandbook
CategoryHandbook-email