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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] [PATCH 2/3] Always use nonblocking
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Date: Wed, 23 Jul 2008 17:44:28 +0100
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To: qemu-devel@nongnu.org
Cc: Gerd Hoffmann <kraxel@redhat.com>

On Wednesday 23 July 2008, Gerd Hoffmann wrote:
> Anthony Liguori wrote:
> > Gerd Hoffmann wrote:
> >> Comments on this one?
> >
> > Checking every 100ms for every pty device really makes me cringe.
>
> Only when unconnected, and the interval can be changed.
> And I'm certainly open for better ideas ...

Anything that requires periodic polling is almost certainly wrong.

If it's unconnected then why do we need to poll at all? If we're discarding 
data then we aren't going to retry, so it should be sufficient to check 
whenever we send data.

Paul