[libvirt] [PATCH] 514532 Fix man page, most operation are synchronous

Daniel P. Berrange berrange at redhat.com
Thu Nov 19 16:34:12 UTC 2009

On Wed, Nov 18, 2009 at 02:31:12PM +0100, Daniel Veillard wrote:
> -Most B<virsh> commands act asynchronously, so just because the B<virsh>
> -program returned, doesn't mean the action is complete.  This is
> -important, as many operations on domains, like create and shutdown,
> -can take considerable time (30 seconds or more) to bring the machine
> -into a fully compliant state.  If you want to know when one of these
> -actions has finished you must poll through virsh list periodically.
> +Most B<virsh> commands act synchronously, except maybe shutdown
> +and domain creation. In those case the fact that the B<virsh>
> +program returned, may not mean the action is complete and you
> +must poll through virsh list periodically to detect that the
> +operation completed.

Shutdown is async, but domain creation is certainly supposed to
be synchronous.    Of course the guest may immediately crash
so appear inactive again just after create returns

Thinking about it, I believe virDomainShutdown/Reboot, and the SetMemory
and SetVcpus are the only two APIs that are allowed to be async, because 
they merely update the guest, but don't wait for it to react.

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