[NNTP] LISTGROUP mandatory (was: Draft 26 pre-2)

[Clive D.W. Feather]

Russ Allbery said:
>> I thought the consensus was to make LISTGROUP a mandatory part of the
>> READER "bundle"?
> I think it was still a bit up in the air, but that does seem to be the way
> that the wind is blowing, so I'm going to declare that consensus and see
> if anyone objects.

Done.

The diffs, for anyone who cares:

* Several examples have READER LISTGROUP changed to READER in the
capabilities list.
* In the definition of the READER capability in 3.3.2, delete the sentence:
    If and only if the LISTGROUP command is implemented,
    there MUST be an argument LISTGROUP.
* Change 6.1.2.1 from "READER with argument LISTGROUP" to "READER".
* In 6.1.2.2:

    The LISTGROUP command selects a newsgroup in the same manner as the
    the GROUP command (see Section 6.1.1) but also provides a list of
+   article numbers in the newsgroup.
-   article numbers in the newsgroup. Except for the range argument and
-   that the 211 response code is multi-line, its behaviour is identical
-   to the GROUP command.

[...]

-   In all other aspects the LISTGROUP command behaves identically to the
+   Except for the range argument and the multi-line data block following
+   the 211 response code, the LISTGROUP command is identical to the
    GROUP command.  In particular, when successful, the command sets the
    current article number to the first article in the group, if any,
    even if this is not within the range specified by the second
    argument.

[The two bits of text sort of duplicated each other, so I rationalized them
into one.]

* In 9.5, remove [WS "LISTGROUP"] from <reader-capability>.
* In Appendix B, change "READER LISTGROUP" to "READER" and, in the second
  table, move LISTGROUP to after LAST. Delete the sentence:

     Where two keywords are given in the capability column, the second is
     an argument to the first.

-- 
Clive D.W. Feather  | Work:  <clive at demon.net>   | Tel:    +44 20 8495 6138
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