I'm afraid I can't agree here. Whether procmail is used directly as an
MDA or invoked through a users .forward, it is still invoke directly
via sendmail. To me, this differs from MUAs which I think of as true
clients (either sending mail via SMTP or receiving mail via POP or
IMAP). The difference is that these types of clients may *call* the
server (through a protocol), but are never *called*. On the other
hand, procmail is invoked (indirectly) by sendmail, so it belongs in
another category.
In all fairness, my definition of MUA may be more restrictive than the
usual definition, but I believe this definition has the advantage of
being more precise and clearly addressing the role of the program as a
component of a message handling system.
Gregory Woodhouse gregory(_dot_)woodhouse(_at_)med(_dot_)va(_dot_)gov
May the dromedary be with you.
----------
From: Keith Moore [SMTP:moore(_at_)cs(_dot_)utk(_dot_)edu]
Sent: Monday, January 12, 1998 2:59 PM
To: Matthew Wall
Cc: Keith Moore; ietf-mta-filters(_at_)imc(_dot_)org; Harald Alvestrand; Paul
Hoffman
Subject: Re: MTA Filters BOF request, LA IETF; Proposed Charter
with few exceptions, the mail transport system should not be
doing mail filtering. the mail transport's job is to deliver
mail, not to make filtering decisions on behalf of the user.
if recipients want to filter their own mail, that's their
business, but then it's a UA-level thing.
I disagree. Filtering is something that *is* done at the delivery
end of the
transport cycle. A "UA" relies on delivery and transport agents to
make a
number of decisions. If it was merely a UA activity, we wouldn't
have
vacation, procmail, .forward, IMAP BB+ -style delivery,
auto-bouncing, or
any current filtering activities done completely without the
participation
of a UA.
vacation and procmail *are* UAs, as are any programs to which mail is
forwarded for the purpose of filtering mail.
I can understand why a ubiquitous filtering language would be useful.
I can also understand how it could cause a great deal of harm, by
making
the behavior of the mail transport system less predictable.
Defining only the language also ignores the security issues. How
are users going to specify such filtering without some means of
authenticating themselves to the filter?
Keith