Cameron Laird's personal notes on procmail

I launched this page to amplify our cover story for the December 1997 Sunworld and the chapter on "Automation" in the second edition of ..., as a service to their readers. While the former article focuses first on combatting spam, both these pieces discuss positive uses for procmail. [explain] You're welcome also to read other articles we've written, including Procmail 'Passthrough' Partners for Powerful E-mail Filtering and [... Oct 2001 OS on filtering ...].

Procmail documents:

Favorite Filters I Have Known include ones [annotate] from

Procmail is easy to set up. The most delicate aspect of a first filter is writing the .forward precisely. Here are a few variations I've encountered:

I have a regret about the article; it is that we didn't say a few more words about the $HOME/.procmail/log file where procmail records its activity. If procmail is doing something different from what you expect, or you want to develop metrics on what procmail does for you, or you just want to understand its operation better, browse the log. Also, be aware that procmail logs can become big; many procmail users periodically erase/archive/replace/... their logs.

Thanks to Richard Hanby and Ric Steinberger who caught the out-of-place '$' in the original release of the article. Thanks also to Jari Aalto, who wisely recommended we should warn readers that

As a precaution, always set SHELL=/bin/sh at the beginning of your .procmailrc. This is a good safety measure.
Jari adds that PATH is also a candidate for explicit definition.
Cameron Laird's personal notes on procmail/