Newsgroups: news.software.b,news.software.c
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From: emv@math.lsa.umich.edu (Edward Vielmetti)
Subject: synthesize a new newsgroup from a bunch of old ones.
Message-ID: <EMV.90May31175714@urania.math.lsa.umich.edu>
Sender: usenet@math.lsa.umich.edu
Organization: University of Michigan Math Dept., Ann Arbor MI.
Date: 31 May 90 17:57:14


what I want to do is something like this.

say you are following something that currently is discussed in
multiple newsgroups, but not any one of them in particular.  I want to
set up some filters within the news batching and unbatching software
that takes all articles which meet certain criteria (akin to what you
might match in a kill file or a keep file) and create a new
"newsgroup" out of them.

I think I can do it given the current C news batching/unbatching
scheme like so.  for point of illustration let's say I'm looking
for anything to do with lex, yacc, or bison or any other compiler
building tools.  I figure that if I search comp.unix.*, comp.lang.*,
comp.compilers, and gnu.* I'll probably hit everything.  

First, an entry in the sys file queues up a bunch of articles in
likely target groups.

YACC:comp.unix.all,comp.lang.all,comp.compilers,gnu.all/world:F:\
	yacc-articles/togo

next, the moral equivalent of an unbatcher looks at this file of
articles, greps each one for the magic strings, and writes out
another file of article names which should be reconstituted into
the new group.  perhaps, if it gets a full feed of possibly interesting
groups, it could parcel them out to a number of different synthetic
groups.

another thing comes along and takes the list of articles and the new
newsgroup name and quietly drops articles into the new group.  you
might call this ex post facto crossposting.  this is potentially
tricky.  I'd be inclined to either hard link or symbolic link the
article into the new directory and update the active file, but -- do
you update the history file as well?

it's not clear that there's an easy way of sending these articles out
to downstream sites -- nor would you want to in most cases.  if you 
did you'd want to generate new message-id's too & rewrite some headers.

expire might also be tricky depending on how many people are reading the
synthetic group -- one reasonable application of this would be to save
useful postings in otherwise trashy groups.  thus you could expire hard
on the unfiltered group and be looser with the synthetic one.

I want this sort of thing to meet these needs:

comp.archives, so I don't have to hunt through every group for stuff --
it would be damn nice to have it all dropped in one place for me.

several synthetic comp.windows.x subgroups; also synthetic comp.sys.sun
subgroups based on the moderator's existing work.

thanks for any input (or of course, working code....)

--Ed

Edward Vielmetti, U of Michigan math dept <emv@math.lsa.umich.edu>
comp.archives moderator