On May 16, 10:51am, Wolfgang Rupprecht wrote:
} 
} Michael Graff writes:
} > How hard would it be to add this to qmail?  I can't imagine it is that
} > hard,
} 
} I'm told that there is an unofficial patch to run procmail over each
} incoming msg.  This procmail is run during the SMTP phase, so SMTP can
} blow off the sending site it there is something in the header it
} doesn't like.

     This is a rather gross concept.  It's also extremely wasteful of
resources, since it means spawning a second process to handle all
incoming SMTP transaction.  If you want to do something like this,
then the right was to do it would be to put a stripped down procmail
engine into qmail's smtpd.  It should be just enough to say yay or nay
to the incoming mail.  All the stuff to do with forwarding mail,
calling external programs, etc. should be stripped.

} Seeing how none of the unofficial patches are ever incorporated into
} qmail (NIH ???), its highly unlikely that something that execs another
} program and adds quite a bit of code will make it into the mainstream,
} audited and secure core of the qmail distribution.

     Although NIH in general is bad, I would have to agree in this
particular case.  Audited by whom?  (The author doesn't count.)  I
wouldn't classify it as secure, but that's a different rant for
another day.

} John Nemeth <jnemeth@cue.bc.ca> writes:
} > >      Having one MTA feed another is not only silly, but grossly
} > > wasteful of resources.  However, it would be nice if homeworld didn't
} > > run qmail, since it is grossly wasteful of bandwidth.
} 
} It also only adds the equivalent of one delivery load.  Lets say we
} have a 1000-reader mailing list.  Having sendmail prescreen the
} headers will only add one more MTA hand-off to the equation of 1000
} MTA handoffs per message.  Not much of a CPU load.

     It's a gross waste of resources (both people and machine).  If
you're going to have sendmail prescreen the mail, then have it do the
delivery as well.  It would be redundant to have sendmail pass the
item onto another MTA just to do all the work that it just did.

} It is someone grotty to have to maintain both a sendmail and qmail
} setup.

     That's an understatement.

}-- End of excerpt from Wolfgang Rupprecht