Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.csd.uwm.edu!uakari.primate.wisc.edu!ames!amelia!dell
From: dell@amelia.nas.nasa.gov (Thomas E. Dell)
Newsgroups: news.software.b
Subject: Re: Cnews active min field (WAS Re: Cnews setuid(geteuid))
Message-ID: <3013@amelia.nas.nasa.gov>
Date: 26 Aug 89 23:39:05 GMT
References: <1989Jun25.174800.13276@utzoo.uucp> <10931@ibmpcug.UUCP> <1989Jun20.213129.8095@utzoo.uucp> <10947@ibmpcug.UUCP> <26-Jun-89.101532@192.41.214.2> <1989Jun28.154945.13805@utzoo.uucp> <1812@ucsd.EDU>
Reply-To: dell@amelia.nas.nasa.gov (Thomas E. Dell)
Organization: NASA Ames Research Center, Moffett Field, CA
Lines: 27

In article <1812@ucsd.EDU> brian@ucsd.edu (Brian Kantor) writes:
>What deficiency?  NNTP will a) give you the next article, and b) list
>and article either by article-id or by ordinal number in the current
>newsgroup.
>
>Oh, you wanted a list of valid article numbers ahead of time?  You can
>get them the same way you would if you couldn't directly read the
>directory; given a minimum number and a maximum number, you could (if
>you really wanted to) step through and stat the corresponding filename.
>NNTP will let you do that if you wish.
>
>At the time we designed the protocol, no news reader needed a list of
>all article numbers ahead of time.  To my knowledge, still none do.
>	- Brian

One of Rn's problems is that it does indeed have significant performance
loss when skipping through large amounts of nonexistant articles. This is
also true for Rrn, I've noticed. 

I've written something that uses opendir() etc to get minimum/maximum
number (hilo) of messages. Unfortunately I have not extended this because
of the NNTP problem. It is VERY useful for a newsreader to have information
about valid article numbers, and I hope someone with influence over NNTP's
direction will realize there is a demand for this feature.

              - T0M
           (dell@ames-nas.arpa)