[Gnu-arch-users] Re: the dangers of no reply-to munging

[Miles Bader]

MJ Ray <address@hidden> writes:
> How do you tell, from M-F-T, whether the sender is subscribed?

Presumably because the M-F-T header will contain the sender's address if
he's not subscribed, and won't contain it if he _is_ subscribed.

> You might also like to ask "Given only M-F-T and other non-List-*
> headers, how can I tell if a message is from a mailing list?"

Actually, I'd like to ask `Why do you care if the message is from a mailing
list?'  The `important thing' (at least in the context of this discussion)
is that followups go to the `right place.'

> "What does M-F-T actually give that isn't present elsewhere?"

Presuming the agent who added M-F-T (either the real sender, or the MLM)
was smart about it, because it reflects exactly the information you asked
about above -- whether or not the sender is on the mailing list, and thus
whether followups should omit the sender or not.

Note that in an ideal system, the _sender_ should add M-F-T headers, if
he can do it `intelligently' (with knowledge of the sender's mailing-list
subscriptions), so it also can do the right thing in the case where the
message recipients include _multiple_ mailing lists, and the sender is on
some, but not all of them (basically M-F-T should omit the sender if he's
on _any_ of the mailing lists to which the message was sent).  However,
the failure mode here is benign -- at worst, duplicate copies get sent
(if someone follows up to a copy of the message added by the MLM for a
non-subscribed mailing list, but the recipient headers also included a
subscribed mailing list).

-Miles
-- 
97% of everything is grunge