[NNTP] LISTGROUP

[Mark Crispin]

On Mon, 25 Apr 2005, Clive D.W. Feather wrote:
>>> * Still undecided what to do if:
>>>  - the range is inverted (e.g. 5-1).
>> I'll argue, weakly, that 5-1 should be the same as 1-5.
> I disagree.

5-1 is a curiosity as long as there aren't extensions such as "*" for 
"highest assigned article number".  However, it becomes important when 
such extensions exist.

> Wrong: if it's a syntax error, the server MUST return a 501 response.

That is a silly argument.

It is impossible to test or certify for such a requirement, since the set 
of syntax errors is unbounded.  Therefore, it is a requirement without 
force.

Such a requirement would be widely disregarded.  It is doubtful that there 
is any server implementation of any non-trivial protocol which attempts to 
adhere to such a requirement, much less actually adheres to it.

Taken literally, such a requirement forbids future extension, since 
extensions are syntax errors in the unextended protocol.

NNTP is perhaps the sloppiest protocol in the entire messaging suite, so 
to pretend that there is rigor today is pointless.

The correct position to take is that a server returns a 501 response to a 
detected syntax error; however a client must not rely upon this behavior 
and must not send syntax errors.

-- Mark --

http://staff.washington.edu/mrc
Science does not emerge from voting, party politics, or public debate.
Si vis pacem, para bellum.