Newsgroups: news.software.b
Path: utzoo!henry
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: Passing on unwanted groups
Message-ID: <1990Aug11.031724.11712@zoo.toronto.edu>
Organization: U of Toronto Zoology
References: <1990Aug7.143458.1770@sci.ccny.cuny.edu> <747@sci34hub.UUCP> <1990Aug9.152342.29200@zoo.toronto.edu> <1990Aug9.205409.28967@sci.ccny.cuny.edu> <15112@.la.locus.com>
Date: Sat, 11 Aug 90 03:17:24 GMT

In article <15112@.la.locus.com> geoff@ITcorp.com (Geoff Kuenning) writes:
>The only problem I can see with this scheme is that expire, upon seeing
>that an article has disappeared, might not keep the message-ID around for
>duplicate-prevention purposes.  My guess is that this is similar to
>cancelled messages, and thus not a problem, but I haven't investigated
>personally.  Do Henry or Geoff care to comment?

I cannot speak for B News expire, but C News expire does not even look to
see whether the article exists until it's time to expire it.  And even then,
if it's missing, C expire just says "hmph, must have been cancelled", and
carries on.  Cancellation removes the article but does not affect the
history file, because it's seriously painful to alter a history-file
entry that is already in place, and it's not worth the trouble.

Neither expire nor the news readers can see any difference between an
article which has been cancelled and one that has mysteriously disappeared
for reasons unknown; since the first case is a normal occurrence, there
is no problem with the second.

In any case, *all* message-IDs stick around in the history file for
duplicate prevention.
-- 
It is not possible to both understand  | Henry Spencer at U of Toronto Zoology
and appreciate Intel CPUs. -D.Wolfskill|  henry@zoo.toronto.edu   utzoo!henry