Kjetil Torgrim Homme writes:
> PS. There is an option to Sendmail to suppress duplicate mail, but
> naturally, that will only work locally. Ie. if Brent Chapman
> (@greatcircle.com) posts something to list-managers, no one should get
> more than one copy.
Well, actually this won't usually work when you are using mailing list
software. The sendmail duplicate-suppression can only work when
the actual addresses are available to sendmail at the time of alias
expansion (i.e., direct aliases from the aliases file, or ":include:"
list expansion). Typically, with mailing list software, the list alias
will resolve to sendmail's "prog" mailer, since it is a pipe to a
program (like Majordomo's "resend" script) that modifies headers, etc.
By the time that program has done whatever it does and then re-invokes
sendmail to expand the actual list and deliver the messages, the first
copy of the message (the one with the individual address in the "To:"
line) has already been delivered (or at least separately queued).
Michael C. Berch
email@example.com / firstname.lastname@example.org