gnus loops if nntp server connection closes without sending output

[Ken Raeburn <raeburn@cygnus.com>]

I'm trying to contact an nntp server through a tcp forwarder (ssh).
The forwarder accepts the connection, but then if the news server
cannot be reached, it closes it.

The loop in nntp-wait-for does not appear to handle a closed
connection, where no amount of waiting will produce output from the
closed pipe.  So nntp-open-connection loops endlessly.  I tried making
nntp-wait-for simply raise an error in this case, but that aborts the
gnus invocation, and doesn't permit the reading of groups from other
servers.

I'm looking at qgnus-0.32, but the announcements for 0.33 and 0.34
don't indicate any change in this area.

Ken