🚀 go-pugleaf

In <749@mcgill-vision.UUCP>, mouse@mcgill-vision.UUCP (der Mouse) writes:
> Smail uses sendmail, right?  How does smail persuade sendmail to put
> different things in the From_ and From: lines?  I never managed to make
> sendmail change the From_ line without changing the From: line at the
> same time.

No persuasion is necessary.  Let's think this through...

General Scenario: UUCP thru mail arrives at site snarf.  rmail invokes
sendmail as

	sendmail -ffoo!bar!sender mumble!scream!recipient

The relevant message headers are:

	From foo!bar!sender <ctime-date-string>
	From: sender@sushi.bar.com

It is sendmail's job to convert this combined input into a call to uux:

	/usr/bin/uux - mumble!rmail '(scream!recipient)'

with the relevant headers modifed to be

	From foo!bar!sender <ctime-date-string> remote from snarf
	From: sender@sushi.bar.com

Notice is that NOWHERE is snarf! prepended to an address. (!)  It will be
prepended to the From_ address by the NEXT host's (mumble's) rmail.  Thus
sendmail can leave the addresses in both From_ and From: alone.  All sendmail
has to do is add the "remote from host" part, and indeed there is a mailer
flag that causes sendmail to do just that.

> > All the standards (822, 976) explicitly say you leave the From: line
> > in domain format - it is not and was never a bang path.
> 
> What if it isn't in domain format originally?  What happens to mail
> that was really truly sent to a bang address?

There is no such thing as a bang address.  Bang syntax is a form of ROUTING,
and as such belongs in the message envelope, not in the message headers.
The From_ line is not a header, it is part of the message envelope.

> Where do we get a fix to just this problem, without dragging in all the
> rest of smail?

Again, sendmail will already generate the From_ lines with the "remote from
host" stuff on the end, so what else is there to do?  All you have to do is
make sure your configuration does not alter bang routes and be sure the 'U'
flag is part of the mailer definition that invokes uux (I'm sure it is
already).

So you don't HAVE to have smail to be able to conform to the standard.  But
the program is already written, works, and is GREAT!  Why NOT use it??  Could
it be that you enjoy hand-routing all your UUCP mail?

kyle jones   <kyle@xanth.cs.odu.edu>
old dominion university, norfolk, va