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:
                os.unlink(filename)
            except:
                pass
            try:
                handle = os.open(filename, os.O_CREAT | os.O_EXCL | os.O_RDWR)
                try:
                    try:
                        pid = str(os.getpid())
                    except:
                        pid = 'unable to get pid'
                    os.write(handle, pid)
                except:
                    pass  # Ignore this as it's pretty much optional
            except:
                self._release_mutex = NULL
                self._acquired = False
            else:
                def release_mutex(*args, **kwargs):
                    # Note: can't use self here!
                    if not getattr(release_mutex, 'called', False):
                        release_mutex.called = True
                        try:
                            os.close(handle)
                        except:
                            traceback.print_exc()
                        try:
                            # Removing is optional as we'll try to remove on startup anyways (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