Re: [BUG]: Gnus randomly refuse to fetch and display articles

[Kevin Greiner <kevin.greiner@vignette.com>]

Xavier Maillard <zedek@gnu-rox.org> writes:

> On 11 oct 2004, Xavier Maillard wrote:
>
>> Hello,
>> 
>> New problem I have since 2 or 3 days now.
>> 
>> Sometimes for an unknown reason, I get this backtrace when
>> trying to display an article:
>> 
>> ,----
>> > Debugger entered--Lisp error: (error "Server closed
>> > connection") signal(error ("Server closed connection"))
>> > error("Server closed connection") apply(error "Server closed
>> > connection") nntp-report("Server closed connection")
>> > nntp-accept-process-output(nil) byte-code("\b =ƒ%
>> > gnus-async-wait-for-article(15716)
>> > gnus-async-request-fetched-article("nntp+gnu-rox.org:gnus.ding"
>> > 15716 #<buffer *Article*>)
>> > gnus-request-article-this-buffer(15716
>> > "nntp+gnu-rox.org:gnus.ding") gnus-article-prepare(15716 nil)
>> > gnus-summary-display-article(15716 nil)
>> > gnus-summary-select-article(nil nil pseudo)
>> > gnus-summary-scroll-up(1)
>> > call-interactively(gnus-summary-scroll-up)
>> `----
>> 
>> It doesn't happen every time but in a random fashion. I can for
>> example read 10 articles in a row and then, Gnus refuse to
>> display one. Dunno what can cause this to happen since I have
>> this behavior when plugged or not.
>
> Any taker ?
>
> I tried to (setq nntp-record... t) and switched to the
> corresponding buffer but all I get is:
>
> ,----
> | 20041012T002908.472 gnu-rox.org *** CALLED nntp-report *** 
> `----
>
> This is kind of annoying since I don't really know what can block
> this.
>
> Any help *grantly* appreciated.
>
> Hint: I just upgraded my local copy of Gnus from CVS and still
> got this after having restarted Gnus.

The problem is that some nntp servers close idle connections to
conserve their resources while others punish a client that leaves idle
connections open by ignoring future requests.  The nntp backend
handles both of these problems by wrapping the nntp command logic in
the nntp-with-open-group form.

Just guessing but I'd bet that the problem is that
gnus-async-wait-for-article binds proc.  The nntp-with-open-group
recovers from a closed nntp connection by opening a new connection.
The gnus-async-wait-for-article nevers sees that new connection
because it binds proc before it enters its loop.

So, try replacing (nntp-accept-process-output proc) in
gnus-async-wait-for-article with (nntp-accept-process-output
(nntp-find-connection (current-buffer))).

Kevin