I figured it out. The way to do it is to use the Generic Desktop Page (0x01) Keyboard (06) (and Keypad (07) for completeness) for use with IOHIDManagerSetDeviceMatchingMultiple, and then the input value callback gets Keyboard/Keypad Usage Page (0x07) stuff. For example, to setup a an HIDManager for all keyboards/keypads, one could do something like: … Read more
NSDictionary and the other collection classes are actually class clusters: several concrete subclasses classes masquerading under the interface of a single class: they all provide the same functionality (because they are subclasses of the same class — in NSDictionary’s case, this involves the three “primitive methods” -count, -objectForKey:, and -keyEnumerator), but have different internal workings … Read more
If you use performSelectorInBackground:withObject: to spawn a new thread, then the performed selector is responsible for setting up the new thread’s autorelease pool, run loop and other configuration details – see “Using NSObject to Spawn a Thread” in Apple’s Threading Programming Guide. You’d probably be better off using Grand Central Dispatch, though: dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{ … Read more