Sendmail::Milter - Perl interface to sendmail's Mail Filter API

Copyright Notice

Copyright (c) 2000-2001 Charles Ying. All rights reserved. This program is
free software; you can redistribute it and/or modify it under the same terms
as sendmail itself.

The interpreter pools portion (found in the intpools.c, intpools.h, and
files) of this code is also available under the same terms as perl itself.

About Sendmail::Milter

Sendmail::Milter provides users with the ability to write mail filters in Perl
that tightly integrate with sendmail's mail filter API.

With this module, you can define and register Perl callbacks with the Milter
engine. This module calls your perl callbacks using interpreters from a
threaded persistent interpreter pool. Milter contexts are presented using an
object-oriented style interface for performing operations on a Milter context.

The main project web page for this module is:


Sendmail::Milter has been tested with the following:

    sendmail 8.12.1 built with -DMILTER
    perl 5.6.1 built with -Dusethreads

You can find the latest version of sendmail from:

You can try this module out with newer versions of Perl, hopefully interpreter
threads support will come out of its experimental state in the future.

You'll also need to have an operating system with a viable POSIX threads

This module has only been tested on FreeBSD 4.0-RELEASE. Your mileage may vary.

Sendmail::Milter uses the new perl_clone() call in 5.6.0 to make copies of the
Perl interpreter for its interpreter pools (see intpools.c and intpools.h). See
the perldelta manpage for more information on this feature.

Before You Begin

Read the libmilter/README file that comes with the sendmail source
distribution to find out how to build sendmail with the Mail Filter API.

Building Sendmail::Milter

Begin by building sendmail, libmilter, and perl with -Dusethreads. Next,
perform the following commands:

% perl Makefile.PL ../sendmail ../sendmail/obj.FreeBSD.4.0-RELEASE.i386
% make
% make install

The paths ../sendmail and ../sendmail/obj.FreeBSD.4.0-RELEASE.i386 should point
to the sendmail source tree and the sendmail build directory, respectively.

Using Sendmail::Milter

See the pod documentation for complete information on writing your own mail
filters with this module.

Testing the sample mail filter
----------------------------------------, a sample test case has been provided. You can run it by using the
following command:

% perl myfilter /etc/mail/

But before you do that, add a line similar to:

INPUT_MAIL_FILTER(`myfilter', `S=local:/var/run/perl.sock')dnl

to your .mc file. isn't terribly interesting, but should give you a
good feel for how mail filters are written with Sendmail::Milter.

Mailing List

You can subscribe to the mailing
list. Instructions on how to do so can be found off the Sendmail::Milter
project page.