ietf-nntp Where are we at?

[Charles Lindsey]

In <yl7kkjs8h9.fsf at windlord.stanford.edu> Russ Allbery <rra at stanford.edu> writes:

>What's improper about trying and seeing if you get a 503 response?  What
>problem are you trying to solve?

Because it's messy to have to invent a test case just to find whether some
feature is supported. I am thinking of the case where the client has a
large list of things it wants to query using HDR, and needs to use a
different strategy depending on whether the server supports that
particular header in its HDR. It has three choices:

1. Start off its big loop on the assumption that the header works. Oops!
we got a 503. Abandon the loop, initialize everything to do it the other
way, and start over.

2. Before starting on the big loop, generate an artificial test case just
to see whether that header is supported.

3. Use LIST EXTENSION to see whether that header is supported.

Yes, they can all be made to work but, as a writer of the client software
I know which facility I would prefer to use.

We invented the LIST EXTENSION command precisely so that clients could
plan ahead which strategies to use. It is there. Why not use it? It's not
as if it would be difficult for the server to provide.

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
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