Julien ÉLIE | 15 Feb 20:44 2011

[NNTP] Wording for the "x" status in RFC 6048

Following a discussion with Alfred Hönes, who reported:

> The only place where I got stuck in RFC 6048 was in Section 3.1,
> in the 6th paragraph on page 17.  The RFC says:
> 
> |  A newsgroup with status "x" is a newsgroup with status "n", except
> |  that articles from peers are not accepted.  [...]
> 
> Given the definition from RFC 3977 that you quote slightly above,
> at the bottom of page 16,
> 
>     "n"  Posting is not permitted.
> 
> the "except that" does not make sense to me.
> 
> (In contrast, where the 7th paragraph says ...
> 
> |  A newsgroup with status "j" is a newsgroup with status "y", except
> |  that (1) local postings are not accepted, (2) articles received from
>     a peer that are crossposted to one or more valid groups are filed
>     only into those valid groups, and (3) articles received from a peer
>     that are not crossposted to any valid groups are not filed into any
>     newsgroup, but are still propagated to other peers, if appropriate.
> 
> ... "except that" makes perfect sense.)
> 
> Reading the subsequent explanations and examples, I conclude that
> the RFC 3977 status field values only affect local posting and
> are transparent to forwarding behavior.
> 
(Continue reading)

Julien ÉLIE | 15 Feb 20:44 2011

[NNTP] Terminology valid/invalid in RFC 3977

Following a discussion with Alfred Hönes, who reported:

> terminological overloading,
>     leading to ambiguity and under-specification
>
> Within the RFC text, the terms "valid", and in particular, "invalid",
> are used with three very distinct semantics.
> These terms could mean:
>
> a)
> conformance/non-conformance with the prescribed syntax (ABNF) for
> a message (command/reply), or one of its components, e.g., talking
> about a "valid response code" (Section 5.1.1 et al.)

I believe this one is pretty clear and without any ambiguity.

Let's deal with the other uses below.

> b)
> the special value "invalid" introduced in Section 6.1, on page 36,
> for the two NNTP session state variables specified:
>
>   The following commands are used to set the "currently selected
>   newsgroup" and the "current article number", which are used by
>   various commands.  At the start of an NNTP session, both of these
>   values are set to the special value "invalid".
>                                       ^^^^^^^^^

I think it is OK.

(Continue reading)

Julien ÉLIE | 15 Feb 20:45 2011

[NNTP] Clarification of intra-document references in RFC 3977

Following a discussion with Alfred Hönes, who reported:

 > clarification of intra-document ref.
 >
 > Within Section 2 of RFC 3977, the first paragraph on page 6 says:
 >
 >                       [...].  In some cases, however, they do assume that
 >     the currently selected newsgroup (see the GROUP command,
 >     Section 6.1.1) is invalid; when so, this is indicated at the start of
 >     the example.  [...]
 >
 > The "currently selected newsgroup" is introduced in Section 6.1 (see
 > next quotation below); as such, the clause therein,
 >
 >        (see the GROUP command, Section 6.1.1)
 >
 > should more appropriately have been replaced by:
 >
 >        (see Section 6.1)
 > or:
 >        (see Section 6.1 ff.)

I do not know well what to do with that.
Here is my answer to Alfred:

I do not think the text should be changed this way.
In Section 6.1.1, we have:

    The GROUP command selects a newsgroup as the currently selected
    newsgroup and returns summary information about it.
(Continue reading)

Julien ÉLIE | 15 Feb 20:47 2011

[NNTP] Consistency in replies to 420 in RFC 3977

Following a discussion with Alfred Hönes, who reported:

> Appendix C, on page 119, says:
> 
>     Response code 412
>        Generated by: ARTICLE, BODY, GROUP, HDR, HEAD, LAST, LISTGROUP,
>        NEXT, OVER, STAT
>        Meaning: no newsgroup selected.
> 
>     Response code 420
>        Generated by: ARTICLE, BODY, HDR, HEAD, LAST, NEXT, OVER, STAT
>        Meaning: current article number is invalid.
> 
> Please be aware of the different wording used:
>        "no newsgroup selected" vs. "current article number is invalid"
> 
> These two phrases, respectively, are used in a totally consistent way,
> throughout the RFC, in the specification of possible command responses
> when it comes to referring to these two response codes.
>
> The text, "no newsgroup selected", also appears in all examples
> where response code 412 is returned by the server.
> 
> Interestingly enough, all examples in the RFC where the response
> code 420 is returned by the server consistently do *not* use the
> above quoted phrase from Appendix C, but instead say:
> 
>        [S] 420 No current article selected

Well seen :-)
(Continue reading)

Julien ÉLIE | 15 Feb 20:56 2011

[NNTP] Suggestion of examples for 412 semantics in RFC 3977

Just a few examples that could be added to RFC 3977.

Following a discussion with Alfred Hönes, who reported:

> (iv)  particulars of the 412 semantics
> 
> The LISTGROUP Usage (Section 6.1.2.1, on page 39) contains the note:
> 
>     [1] The 412 response can only occur if no group has been specified.
> 
> The LISTGROUP Description (Section 6.1.2.2, on mid-page 40) says:
> 
>     The LISTGROUP command selects a newsgroup in the same manner as the
>     GROUP command (see Section 6.1.1) but also provides a list of article
>     numbers in the newsgroup.  If no group is specified, the currently
>     selected newsgroup is used.
> 
> |  If the group specified is not available on the server, a 411 response
> |  MUST be returned.  If no group is specified and the currently
> |  selected newsgroup is invalid, a 412 response MUST be returned.
> 
> The second paragraph quoted could be interpreted to say, using the
> notation proposed above:
> 
>     If the group specified is not available on the server, a 411 response
> |  MUST be returned.  If no group is specified and the currently
> |  selected newsgroup is `invalid`, a 412 response MUST be returned.
> 
> And in this interpretation, it would have to be presumed that when
> (no group is specified and) the "currently selected newsgroup" has
(Continue reading)


Gmane