Begin forwarded message:
> From: Henrik Sperre Johansen <[email protected]> > Date: April 18, 2010 2:24:45 AM GMT+02:00 > To: Squeak Virtual Machine Development Discussion > <[email protected]> > Subject: Re: [Vm-dev] InputSemaphore on Windows > Reply-To: Squeak Virtual Machine Development Discussion > <[email protected]> > > On 16.04.2010 01:07, Andreas Raab wrote: >> >> On 4/15/2010 3:18 PM, Henrik Sperre Johansen wrote: >>> Is there a reason why this isn't signalled when inputSemaphoreIndex > 0? >> >> None. It just doesn't bite me. If it did I would've fixed it already. Got >> patch? > Not yet, thought I'd ask the question if there was any good reason not to do > so first :) > The reason I'd like it to be so, is that Pharo already includes a an > EventSensor (InputEventFetcher) which relies on this, and abolishes the > polling of EventSensor, but it's not used by default since InputSemaphore is > not signaled on all VM's. The code should be easily* portable to Squeak as > well. >> >>> In sqWin32Window.c, the comment for synchronizedSignalSemaphoreWithIndex >>> looks somewhat scary... >>> But looking at the svn logs, it seems it never was used in the >>> record...Event() functions at all, so I wondered if a problem was >>> encountered before svn was in use that lead to its removal, or if it's >>> just not done by default? >> >> The short answer is that there are so many potential issues with handling >> semaphore signals properly that at some point I just gave up. At this point, >> there is no reliable way to deliver semaphore signals, they can and they >> *do* get dropped (we've proven that). > As far as I could read from the latest thread about it on the Squeak list > http://n4.nabble.com/More-Delay-Semaphore-fun-td67556.html#a67556, this is an > issue mostly when the the waiting/signaling process is terminated, which > would (probably... ) not be the case for an event fetcher. > > If I get the time to make any progress** I'll send you the modified file for > review. > > Cheers, > Henry > > *As in, I haven't done it, but the code should run on both platforms. > ** Something buildable, which works as expected when InputEventSensor is > active on Pharo _______________________________________________ Pharo-project mailing list [email protected] http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
