recipe-578998.py 文件源码

def __init__(self, mutex_name):
            check_valid_mutex_name(mutex_name)
            filename = os.path.join(tempfile.gettempdir(), mutex_name)
            try:
                handle = open(filename, 'w')
                fcntl.flock(handle, fcntl.LOCK_EX | fcntl.LOCK_NB)
            except:
                self._release_mutex = NULL
                self._acquired = False
                try:
                    handle.close()
                except:
                    pass
            else:
                def release_mutex(*args, **kwargs):
                    # Note: can't use self here!
                    if not getattr(release_mutex, 'called', False):
                        release_mutex.called = True
                        try:
                            fcntl.flock(handle, fcntl.LOCK_UN)
                        except:
                            traceback.print_exc()
                        try:
                            handle.close()
                        except:
                            traceback.print_exc()
                        try:
                            # Removing is pretty much optional (but let's do it to keep the
                            # filesystem cleaner).
                            os.unlink(filename)
                        except:
                            pass

                # Don't use __del__: this approach doesn't have as many pitfalls.
                self._ref = weakref.ref(self, release_mutex)

                self._release_mutex = release_mutex
                self._acquired = True