> > In practice, you’d actually initialize the semaphore like this: > >> dsema = dispatch_semaphore_create (0); // start with a zero count >> dispatch_semaphore_signal (dsema); // increment to the number of >> resources in the pool. > > That’s because if you create the semaphore with a non-zero count, then later > try to release the semaphore object when its count is something different > (which can happen if you have a more complex loop that you break out of), > your app will crash. The API design assumption is that if you didn’t free all > the original resources, your app has a bug (which I happen to think is bogus > reasoning, but anyway…).
Wow, I’ve never come across that issue. But I don’t see how incrementing it after creating it is any different from creating it with a non-zero count. Either way, if you have resources available, the count will be non-zero, and you will crash if you try to deallocate. But I’m somewhat sure I’ve never seen a crash like that. Maybe I was just lucky? _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
