jmendeth/PyOpenNI — Issue #2: Unregistering a callback twice crashes
Author: jmendeth
Created: 2011-12-01 18:21:00+00:00
State: open
Labels: bad-using, callback, crash

If you unregister a callback more than once (calling the `unregister` method with the same handle) it crashes.
For example:

```python
gest = GestureGenerator()
gest.create(context)
def gesture_recognized(src, gesture, id, end):
# Whatever
def gesture_progress(src, gesture, pos, progress):
# Whatever

handle = gest.register_gesture_cb(gesture_recognized, gesture_progress)
gest.unregister_gesture_cb(handle) # Success
gest.unregister_gesture_cb(handle) # BOOM!
```