[NNTP] Article Numbers Becoming Invalid (RFC 3977)

[Russ Allbery]

Julien ÉLIE <julien at trigofacile.com> writes:

> GROUP defines the "first article in the group at the moment of selection"
> as the "reported low water mark".  I'm OK with that.

> But LAST uses a different wording:

>   If the current article number is already the first article of the
>   newsgroup, a 422 response MUST be returned.  If the current article
>   number is invalid, a 420 response MUST be returned.  If the currently
>   selected newsgroup is invalid, a 412 response MUST be returned.  In
>   all three cases, the currently selected newsgroup and current article
>   number MUST NOT be altered.

> It is NOT the *first* article here, for 422.  I suggest to reword the
> sentence this way:

>   If the current article number is already lower or equal to the lowest
>   existing article number (if any) in the newsgroup, a 422 response MUST
>   be returned.

> It will fix the consistency of the terminology and also deal with the
> edge-case you mention.  Same for NEXT.

Shouldn't we go ahead and use the same terminology?  Something like:

    If the current article number is invalid, a 420 response MUST be
    returned.  If the current article number is equal to or lower than the
    reported low water mark, a 422 reponse MUST be returned.  [...]

This also reverses the order so that it's clearer that an invalid article
number takes precedence in determining the return code.

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