Re: [Libvir] Re: Asynchronous notifications of domain start/stop

On Wed, Jul 18, 2007 at 12:57:37PM +0100, Richard W.M. Jones wrote: > In the qemu case I'm not sure how to modify qemu_driver.c to handle > this. One for Dan Berrange to comment on. We should not explicitly expose 'the xenstore filehandle', or 'the libvirtd' filehandle per-se. Instead we should provide an API which lets application register callbacks for adding/removing file handles to an event loop. We in fact already have this - look at the src/event.h file. So if we make this part of the official public API, then applications merely need provide an impl of the virEventAddHandleFunc and virEventRemoveHandleFunc. The underlying libvirt drivers can thus invoke these callbacks as required, be it with the XenStored filehandle, a XenAPI filehandle, a libvirtd fd or something else. We can provide sample impls of the virEventAddHandleFunc and virEventRemoveHandleFunc code for GLib and/or QT in a libvirtglib.so and libvirtqt.so add-on libraries. This allows for easy integration with most GUI apps, while also allowing integration with custom home brew event loops. This is how DBus provides event loop integration without tieing itself to a specific impl & it works very nicely.