[comp.soft-sys.andrew] handling messages with missing 'From:' lines

bill@allegra.tempo.nj.att.com (Bill Schell) (09/28/90)

A few of the mailers around here like to send out messages with valid
'From' header lines, but with no 'From:' header line  (note the absence
of a colon in the first case).  When messages gets these, it lists the sender
as "<unknown sender>".  Does anyone else have this problem?  I believe
that this is semi-typical in the UUCP world.   How would one go about
making messages look at the 'From' line if the 'From:' line is missing?

Thanks very much,

	Bill Schell
	AT&T Bell Labs, Murray Hill, NJ
	bill@allegra.att.com

PS: here's a typical message header of the type I mentioned

--------------------
 From alice!bill Tue Sep  4 11:19:20 1990
 Date: Tue, 4 Sep 90 11:19:03 EDT
 To: bill@allegra.att.com
 .
 .
 .

Craig_Everhart@TRANSARC.COM (09/28/90)

Messages, and indeed AMS, is an RFC822 mail user agent.  It assumes that
incoming messages are roughly RFC822-conformant.

The ``From_'' line (as it's conventionally referred to) is lots like the
RFC822 Return-path: line in that it contains the envelope-from
information, but it also contains a timestamp-when-received.  It's not
at all a plug-replacement for the From: line.  I would argue, further,
that it's not even a good loose replacement for the From: information.

Sure, somebody could dink with the caption-building code to have it look
for a From_ line for the message sender, but I think it's silly, and
would point the ``problem'' back to the originators of From:-less mail.

		Craig

nsb@THUMPER.BELLCORE.COM (Nathaniel Borenstein) (09/28/90)

Excerpts from internet.info-andrew: 27-Sep-90 handling messages with
miss.. Bill Schell@allegra.temp (716)

> A few of the mailers around here like to send out messages with valid
> 'From' header lines, but with no 'From:' header line  (note the absence
> of a colon in the first case).  When messages gets these, it lists the
> sender as "<unknown sender>".  Does anyone else have this problem?  I
> believe that this is semi-typical in the UUCP world.   How would one go
> about making messages look at the 'From' line if the 'From:' line is
> missing?

I believe that this problem should go away completely with patch 7.  I
haven't yet installed patch 7, but it contains a patch that I sent in,
which is a variant on a previous suggestion by Lennart Lovstrand.  It
will turn the UNIX "From " lines into valid RFC 822 "Return-path"
headers.  The main motivation for this fix was to allow re-sending of
multimedia mail, which was broken when "From " lines were present and
sendmail got its fingers in the pie.  However, a side effect will be to
fix your case, too, because "Return-path" is used as a last resort in
building captions if there's no "From", "Resent-From",  or "Sender"
header.  (See ams/libs/ms/prettyn.c for the whole algorithm.)  Thus,
although that wasn't the intent of the patch, I think it should be fixed
with patch 7.

How's that for service -- the latest patch fixed your bug before you
reported it, and you were told about the fix before anyone from CMU had
time to respond!