Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!samsung!uunet!mcsun!ukc!warwick!nott-cs!lut.ac.uk!elaps
From: elaps@lut.ac.uk (Alan Schwarzenberger)
Newsgroups: comp.mail.elm
Subject: Re: Filter Problem
Keywords: Filter Problem
Message-ID: <1991Jun27.085737.4955@lut.ac.uk>
Date: 27 Jun 91 08:57:37 GMT
References: <5496@texsun.Central.Sun.COM> <1991Jun26.235138.6092@decuac.dec.com>
Organization: Loughborough University, UK.
Lines: 43


  I have filter working on HP9000 (cluster of one 870 and three 855's).
Sendmail is the mail transport agent. ~/.elm has rwx pemissions for me
only. I write the error file to /tmp. There are several quirk's !! First
ignore the man page (if you have the same one as our's) and read "The
Elm Filter System Guide". 
  My .forward file contains:

"|/disks/disk15/el/elaps/bin/forward_filter"
(with all the quotes and everything)

This is a shell script that contains

#!/bin/sh
PATH=/usr/bin:/bin:/usr/lib:/usr/local/bin:/hpc/disks/disk15/el/elaps/bin
export PATH
if test "`hostname`" != hpc
then
	exec sendmail -oi -ba "`whoami`@hpc"
else
	add_unix_from | filter -o /tmp/`whoami`.filter.errors
fi

The add_unix from is a C-program that the System Administrator here
gave me. Apparently (I quote him) "the Elm filter requires a unix style
'From sender date' header at the start of all mail messages. When you
put filter in your .forward file this header is removed by the system
before running your filter program."  So this adds program adds it back
on. It is possible that this is a local modification to sendmail (?). 

The filter rules are in ~/.elm/filter-rules. I always check them with
filter -r as soon as I have altered them. In Elm you HAVE to set
keepempty=ON, as filter failed if the mailbox it wanted to put the
message in didn't exist (I think this was to do with permissions on the
/usr/mail directory. A final quirk is that filter creates the error
file, and then deletes it again if it doesn't find any errors, so check
it's non-zero size to see if any errors have occured. 

-- 

============================================================================
Alan Schwarzenberger    tel +44 509 222849     A.P.Schwarzenberger@lut.ac.uk
International Electronics Reliability Institute, Loughborough University, UK