Re: [Qemu-devel] [PATCH 2/3] Always use nonblocking mode for qemu_chr_open_fd.

[Daniel P. Berrange]

On Wed, Jul 23, 2008 at 11:31:42AM -0500, Anthony Liguori wrote:
> 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 ...
> >  
> 
> I don't have one.  In xenconsoled, once a pty disconnected, it creates a 
> new pty specifically because I don't think there's any sane way to 
> detect reconnection.

The only guarenteed reliable way I know of is using epoll(), but as I
mentioned before that's Linux specific, so not immediately useful unless
we're willing to drop in an alternate epoll() based main loop for Linux
only, and say other OS have to use PTYs in blocking mode.

Daniel
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