Re: [gnus git] branch master updated: n0-17-27-g43f8466 =1= nntp.el (nntp-open-connection): Set TCP keepalive option.

[Lars Magne Ingebrigtsen <larsi@gnus.org>]

> +      (when (and (fboundp 'set-network-process-option)
> +                 (eq (process-type process) 'network))
> +        ;; Use TCP-keepalive so that connections that pass through a NAT router
> +        ;; don't hang when left idle.
> +        (set-network-process-option process :keepalive t))

I don't necessarily disagree with this patch, but I'm wondering what the
use case is.

Keepalive is usually useful (on the client side) if you have a protocol
where you're just sitting sleeping on a socket.  If the server dies,
you'll never get a TCP RST, so the keepalive option will ensure you get
that RST after a while.

However, the NNTP protocol isn't like that.  You send a command and you
get a response.  If you send a command to a server, and it doesn't
recognise you because you've changed IP address or whatever, it'll send
you a RST.

So the NNTP protocol doesn't seem like something that would need a
TCP keepalive option.  But I might be misthinking the use case.

(And, besides, if nntp.el needs keepalive, doesn't all network
connections need it?)

-- 
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