[NNTP] LISTGROUP

[Russ Allbery]

Mark Crispin pointed out a couple of things about LISTGROUP that I think
are worth considering.

First, the command is pretty widely implemented, and it's not obvious
anything useful is gained by making it optional.  If we're going to make
NEWNEWS mandatory, LISTGROUP is a lot easier to implement and more widely
supported right now, and that would get rid of one of our capabilities
that we have to keep track of.

Second, LISTGROUP would be much more useful for some purposes if it took a
range as an optional second argument.  It's pretty trivial to specify that
argument:  it would be identical to the ranges that OVER and HDR take, and
LISTGROUP would function exactly as before but would limit the article
numbers returned to articles within that range.  If there are no articles
in the group within that range, an empty multiline response would be
returned but everything else about LISTGROUP would remain unchanged.

(The reason for this is that, with a client that's tracked read articles
via the normal .newsrc method and knows that, say, articles 1-4000 have
been read, entering a group with "LISTGROUP example.test 4001-" is a
fairly useful thing to do.)

Looking over both of these ideas, the only problem I had with either is
that we're very late in the process to make these sorts of changes.  I
couldn't see any objections at all other than that one, and the latter
extension is so minor, so straightforward, and so easy to describe that
I'd feel silly writing a separate document to specify an extension, adding
a capability modifier for it, etc.  The boilerplate on an I-D would be
bigger than the specification.

How do people feel about looking at these changes at this point?  (Making
LISTGROUP mandatory and adding an optional range argument as described
above.)

-- 
Russ Allbery (rra at stanford.edu)             <http://www.eyrie.org/~eagle/>