Delivered-To or Envelope-To header ...

[Phil Chambers]

On Tue, 2 Jan 2007 12:00:16 +0100 (CET) Christian Kratzer <ck.lists at cksoft.de> 
wrote:

> On Fri, 29 Dec 2006, Phil Chambers wrote:
> 
> >
> > On Tue, 26 Dec 2006 17:17:49 -0400 "Marc G. Fournier" <scrappy at hub.org> wrote:
> >
> >> -----BEGIN PGP SIGNED MESSAGE-----
> >> Hash: SHA1
> >>
> >>
> >> Is it possible to add this where delivery method is lmtp?  I have one person
> >> requesting it, and am not finding anything particularly useful on the subject
> >> ...
> >>
> >> Mainly, what they are looking at is where UserA is aliased to UserB, but they
> >> want to know that the original was sent to UserA for 'sub-filtering' purposes
> >> ...
> >>
> >> I'm using Postfix in front of cyrus imapd .. and v2.3.x of Cyrus IMAPd ...
> >>
> >
> > If a message has been delivered to B because A is in the To: or Cc: then you
> > don't need any extra header lines because you can see it in the To: and Cc:.
> 
> a message is delivery solely by what is in the envelope. The headers
> are irrelevant to mail routing.

I never claimed otherwise! Marc was talking about adding a header for a filter 
to use. I was pointing out that the information was already in the header in a 
particular case.

> 
> > If the message was delivered to multiple recipients because of Bcc: or because
> > of a list (Postfix can't tell the difference) then you are snookered as far as
> > I can see.
> 
> of course postfix can tell the difference.  It has the envelope 
> information. If it did not have the envelope data it could not
> deliver the message anywhere.

You missed my point! Postfix cannot tell whether it received a message because 
of earlier expansion of a list or because of a Bcc: recipient. My point was 
that you would not want to have a header which disclosed all recipients because 
that would break the Bcc: privacy.

I agree that the alternative of producing seperate copies for each individual 
user does not seem like a desirable solution either.

Phil.
---------------------------------------
Phil Chambers (postmaster at exeter.ac.uk)
University of Exeter