Newsgroups: news.software.b
Path: utzoo!henry
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: Cnews artnum in active file
Message-ID: <1990Aug17.163437.2013@zoo.toronto.edu>
Organization: U of Toronto Zoology
References: <1990Aug16.185023.26200@squirrel.mh.nl> <1990Aug17.034849.17801@zoo.toronto.edu> <1990Aug17.071243.16518@looking.on.ca>
Date: Fri, 17 Aug 90 16:34:37 GMT

In article <1990Aug17.071243.16518@looking.on.ca> brad@looking.on.ca (Brad Templeton) writes:
>>of some stupid reader software.  (The lower number is basically an
>>inadequate kludge that smarter software should never look at, but there
>>is a lot of dumb software in the world, sigh...)
>
>Programs do need the minimum -- for creating reasonable sized bitmaps, for
>example.

Programs should do a directory sweep to find out what articles are *actually
present* rather than making the -- unwise and often wrong -- assumption that
there is a nearly-contiguous sequence between min and max.  The code to do
this has to be present anyway, since no reader in its right mind finds the
next available article by a straight linear search.  Directory reading is
cheap and quick.  (There is admittedly a problem with doing this over NNTP,
which is a serious flaw in NNTP but is no excuse when NNTP is not involved.)

>So you can calculate it 300 times per day in every reading session, or
>once, in an upact type program.

The right way to do it is indeed to do it once, but to record useful
summary information rather than just a single number.  Some of the new
fancy newsreaders are starting to do that.
-- 
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