Posted November 26, 1991. More Sendmail Rules to fight spam. A simple mailbot script. Add a line to your sendmail aliases file, and it will send a email message back to whoever sends it mail. You can have mail forwarded on to other people.
Instructions are in the code as comments.
As shipped, the POP daemon from the U of Washington does not check that a user has a valid log-in shell before granting access. I wrote this for a SunOS 4.1.3 system. I have not tried, tested, or ever used any other platform. The changes should be easily diffed and ported to the other platforms. Virtual POP boxes with Qualcomm's popper V2.52.