Duplicate messages

[utzoo!decvax!ucbvax!unix-wizards]

>From Greg at NPRDC Tue Sep 15 13:48:54 1981
The most common reason for multiple copies of a message is multiple invocations
of the mailer.  Very few (if any -- I know of none) mailers try to prevent the
case of having multiple copies active, all of which may be delivering the same
message.  I finally cured the problem here by forbiding all incarnations of our
mailer except the single background daemon.  It means that you may have to wait
as long as ten minutes before the daemon will try to deliver the mail, but that
seems more than reasonable -- have you tried the U.S.Snail Service lately?