Path: utzoo!attcan!uunet!mcsun!unido!mikros!mwtech!mecky!walter
From: walter@mecky.UUCP (Walter Mecky)
Newsgroups: comp.unix.i386
Subject: Mail not delivered in MMDF Mail under SCO UNIX
Summary: Missing mail if more than one deliver process
Keywords: MMDF SCO-UNIX deliver
Message-ID: <678@mecky.UUCP>
Date: 7 Jul 90 01:41:02 GMT
Reply-To: walter@mecky.UUCP (Walter Mecky)
Organization: MIKROS Systemware, Buettelborn/W-Germany
Lines: 39

Anybody using the MMDF mail system is missing mail ? Then
read this.

In the last few month, from time to time I missed some mail.
But I supposed it will be lost on the long way to my system.
By accident (I read an article here with "cleanque" dumping
core and tried it), I found some 50 mails from the last months
laying in the MMDF directory and not delivered to my users.

It was rather annoying, because in most cases I did not know
about the mail and thought "Ok, I asked something and he didn't
answer". I did not notice the problem earlier, because most of
the mail was delivered fine! And it was not a problem of adressing
but of a runtime hazard in the MMDF mail system.

I can reproduce the error with this commands:
	for i in 1 2
	do mail walter <file
	done

sends only _one_ mail to walter, if "file" is bigger than 10KB approx.
The reason is the "deliver" command, which has some lock problem, if
another "deliver" process is running at the same time. The result
is, that "deliver" leaves the workfiles in the MMDF directories
forever. I did never run "cleanque" (shame on me) an so the mails
were never deliverd.

My workaround is to change the "mod=imm" to "mod=reg" in the mmdftailor
file for the local channel and run "deliver" as a background daemon. 
Annoying is, that the original mmdftailor file has "mod=imm" for the
local channel as it is printed in the manual. Amusing is the note in
the SLS 162 docu from SCO: "You cannot reliably run two deliver daemons
on the same channel simultaneously. Doing so will cause some mail to be
sent multiple times." [ I would have been _very_ glad if this happend,
but on my system some mail was sent zero times! ]

Anybody out there who can confirm those things ?
-- 
Walter Mecky	[ walter@mecky	or  ...uunet!unido!mecky!walter ]