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

[Daniel P. Berrange]

On Wed, Jul 23, 2008 at 10:24:58AM -0500, Anthony Liguori wrote:
> Gerd Hoffmann wrote:
> >  
> >>Which means we need our own code for ptys and can't use the generic fd
> >>functions.  I'll go trying cooking up a patch ...
> >
> >Comments on this one?
> >  
> 
> Checking every 100ms for every pty device really makes me cringe.
> 
> Why is libvirt using ptys in the first place?  Why not use unix 
> sockets?  They don't have these problems with state tracking.

The application using libvirt chooses to use PTYs - we're merely
exposing the capability. The virt-console program for interacting
with serial ports uses PTYs because its a configuration that historically
works with both Xen and KVM. It could equally use UNIX sockets, but it'd
still be desirable for PTYs to work better

Daniel
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