Re: Best way to busy-wait in Python 3 / Gtk+ 3?

[Michael Torrie <torriem gmail com>]

On 10/07/2012 08:41 PM, Simon Feltman wrote:
> On Sun, Oct 7, 2012 at 12:29 PM, Filip Lamparski
> <matka poohatka gmail com> wrote:
> > On 7 October 2012 12:58, <jcupitt gmail com> wrote:
> >
> > > To have the load in another process, use a pipe to send worker results
> > > back to the main process, and add the pipe to your gtk main loop as an
> > > event source.
> >
> > Is there any way I could do that? I looked at GLib's main loop and Gtk's
> > main loop, but can't seem to find it.
>
> Is the idea to have a first pass downloading image files in a separate
> process and then use a thread to load them into memory? I don't know
> much about GStreamer but it seems like it might be helpful technology
> in this realm.
>
> For completeness, you can use pythons multiprocessing module along
> with GLib's io watch:
>
> parent, child = multiprocessing.Pipe()
> GLib.io_add_watch(parent, GLib.IOCondition.IN, event_callback)
> process = multiprocessing.Process(target=worker_func, args=(child,))
> process.start()

Maybe the best way is to avoid processes or threads altogether.  Since
downloading this thumbnail is io-bound, not cpu-bound, once you send off
your request, just use io watches to trigger the main loop when
something has come in.