"""Uses the old atexit with added unregister for python 2.x and the new atexit for python 3.x """ import atexit import sys __all__ = ["register", "unregister"] _exithandlers = [] def _run_exitfuncs(): """run any registered exit functions _exithandlers is traversed in reverse order so functions are executed last in, first out. """ exc_info = None while _exithandlers: func, targs, kargs = _exithandlers.pop() try: func(*targs, **kargs) except SystemExit: exc_info = sys.exc_info() except: import traceback sys.stderr.write("Error in atexit._run_exitfuncs:\n") traceback.print_exc() exc_info = sys.exc_info() if exc_info is not None: raise exc_info[0](exc_info[1]) def register(func, *targs, **kargs): """register a function to be executed upon normal program termination func - function to be called at exit targs - optional arguments to pass to func kargs - optional keyword arguments to pass to func func is returned to facilitate usage as a decorator. """ if hasattr(atexit, "unregister"): atexit.register(func, *targs, **kargs) else: _exithandlers.append((func, targs, kargs)) return func def unregister(func): """remove func from the list of functions that are registered doesn't do anything if func is not found func = function to be unregistered """ if hasattr(atexit, "unregister"): atexit.unregister(func) else: handler_entries = [e for e in _exithandlers if e[0] == func] for e in handler_entries: _exithandlers.remove(e) if not hasattr(atexit, "unregister"): # Only in python 2.x atexit.register(_run_exitfuncs)