Python signal.SIG_IGN Examples

def __init__(self, msg_queue, db_interface):
		self.response_queue = msg_queue
		self.log = logging.getLogger("Main.LinkAggregator")

		try:
			signal.signal(signal.SIGINT, signal.SIG_IGN)
		except ValueError:
			self.log.warning("Cannot configure job fetcher task to ignore SIGINT. May be an issue.")

		# LRU Cache with a maxsize of 1 million, and a TTL of 6 hours
		self.seen = cachetools.TTLCache(maxsize=1000 * 1000, ttl=60 * 60 * 6)

		self.queue_items = 0
		self.link_count = 0
		self.amqpUpdateCount = 0
		self.deathCounter = 0

		self.batched_links = []
		self.pending_upserts = []

		self.db_int = db_interface
		self.executor = concurrent.futures.ThreadPoolExecutor(max_workers=6)

		self.check_init_func() 

def _process_wrapper(exit_event, proc_name, function, agent_name=None):
    signal.signal(signal.SIGINT, signal.SIG_IGN)
    signal.signal(signal.SIGHUP, _mutate_config)
    if agent_name:
        process_title = 'octavia-driver-agent - {} -- {}'.format(
            proc_name, agent_name)
    else:
        process_title = 'octavia-driver-agent - {}'.format(proc_name)
    setproctitle.setproctitle(process_title)
    while not exit_event.is_set():
        try:
            function(exit_event)
        except Exception as e:
            if agent_name:
                LOG.exception('Provider agent "%s" raised exception: %s. '
                              'Restarting the "%s" provider agent.',
                              agent_name, str(e), agent_name)
            else:
                LOG.exception('%s raised exception: %s. '
                              'Restarting %s.',
                              proc_name, str(e), proc_name)
            time.sleep(1)
            continue
        break 

def testHandlerReplacedButCalled(self):
        # Can't use skipIf decorator because the signal handler may have
        # been changed after defining this method.
        if signal.getsignal(signal.SIGINT) == signal.SIG_IGN:
            self.skipTest("test requires SIGINT to not be ignored")
        # If our handler has been replaced (is no longer installed) but is
        # called by the *new* handler, then it isn't safe to delay the
        # SIGINT and we should immediately delegate to the default handler
        unittest.installHandler()

        handler = signal.getsignal(signal.SIGINT)
        def new_handler(frame, signum):
            handler(frame, signum)
        signal.signal(signal.SIGINT, new_handler)

        try:
            pid = os.getpid()
            os.kill(pid, signal.SIGINT)
        except KeyboardInterrupt:
            pass
        else:
            self.fail("replaced but delegated handler doesn't raise interrupt") 

def testSecondInterrupt(self):
        # Can't use skipIf decorator because the signal handler may have
        # been changed after defining this method.
        if signal.getsignal(signal.SIGINT) == signal.SIG_IGN:
            self.skipTest("test requires SIGINT to not be ignored")
        result = unittest.TestResult()
        unittest.installHandler()
        unittest.registerResult(result)

        def test(result):
            pid = os.getpid()
            os.kill(pid, signal.SIGINT)
            result.breakCaught = True
            self.assertTrue(result.shouldStop)
            os.kill(pid, signal.SIGINT)
            self.fail("Second KeyboardInterrupt not raised")

        try:
            test(result)
        except KeyboardInterrupt:
            pass
        else:
            self.fail("Second KeyboardInterrupt not raised")
        self.assertTrue(result.breakCaught) 

def parallel_map(function, iterable):
  """Calls a function for every element in an iterable using multiple cores."""
  if FORCE_DISABLE_MULTIPROCESSING:
    return [function(*args) for args in iterable]

  original_sigint_handler = signal.signal(signal.SIGINT, signal.SIG_IGN)
  num_threads = mp.cpu_count() * 2
  pool = mp.Pool(processes=num_threads)
  signal.signal(signal.SIGINT, original_sigint_handler)

  p = pool.map_async(_function_wrapper, ((function, args) for args in iterable))
  try:
    results = p.get(0xFFFFFFFF)
  except KeyboardInterrupt:
    pool.terminate()
    raise
  pool.close()
  return results 

def __init__(self, default_handler):
        self.called = False
        self.original_handler = default_handler
        if isinstance(default_handler, int):
            if default_handler == signal.SIG_DFL:
                # Pretend it's signal.default_int_handler instead.
                default_handler = signal.default_int_handler
            elif default_handler == signal.SIG_IGN:
                # Not quite the same thing as SIG_IGN, but the closest we
                # can make it: do nothing.
                def default_handler(unused_signum, unused_frame):
                    pass
            else:
                raise TypeError("expected SIGINT signal handler to be "
                                "signal.SIG_IGN, signal.SIG_DFL, or a "
                                "callable object")
        self.default_handler = default_handler 

def _import_mp():
    global Process, Queue, Pool, Event, Value, Array
    try:
        from multiprocessing import Manager, Process
        #prevent the server process created in the manager which holds Python 
        #objects and allows other processes to manipulate them using proxies
        #to interrupt on SIGINT (keyboardinterrupt) so that the communication
        #channel between subprocesses and main process is still usable after
        #ctrl+C is received in the main process.
        old=signal.signal(signal.SIGINT, signal.SIG_IGN)
        m = Manager()
        #reset it back so main process will receive a KeyboardInterrupt
        #exception on ctrl+c
        signal.signal(signal.SIGINT, old)
        Queue, Pool, Event, Value, Array = (
                m.Queue, m.Pool, m.Event, m.Value, m.Array
        )
    except ImportError:
        warn("multiprocessing module is not available, multiprocess plugin "
             "cannot be used", RuntimeWarning) 

def __init__(self, task_name, manager, config, timer, base_dir, backup_dir, **kwargs):
        self.task_name  = task_name
        self.manager    = manager
        self.config     = config
        self.timer      = timer
        self.base_dir   = base_dir
        self.backup_dir = backup_dir
        self.args       = kwargs
        self.verbose    = self.config.verbose

        self.runnning  = False
        self.stopped   = False
        self.completed = False
        self.exit_code = 255

        self.thread_count          = None
        self.cpu_count             = cpu_count()
        self.compression_method    = 'none'
        self.compression_supported = ['none']
        self.timer_name            = self.__class__.__name__

        signal(SIGINT, SIG_IGN)
        signal(SIGTERM, self.close) 

def __init__(self, default_handler):
        self.called = False
        self.original_handler = default_handler
        if isinstance(default_handler, (int, long)):
            if default_handler == signal.SIG_DFL:
                # Pretend it's signal.default_int_handler instead.
                default_handler = signal.default_int_handler
            elif default_handler == signal.SIG_IGN:
                # Not quite the same thing as SIG_IGN, but the closest we
                # can make it: do nothing.
                def default_handler(unused_signum, unused_frame):
                    pass
            else:
                raise TypeError("expected SIGINT signal handler to be "
                                "signal.SIG_IGN, signal.SIG_DFL, or a "
                                "callable object")
        self.default_handler = default_handler 

def __init__(self, default_handler):
        self.called = False
        self.original_handler = default_handler
        if isinstance(default_handler, int):
            if default_handler == signal.SIG_DFL:
                # Pretend it's signal.default_int_handler instead.
                default_handler = signal.default_int_handler
            elif default_handler == signal.SIG_IGN:
                # Not quite the same thing as SIG_IGN, but the closest we
                # can make it: do nothing.
                def default_handler(unused_signum, unused_frame):
                    pass
            else:
                raise TypeError("expected SIGINT signal handler to be "
                                "signal.SIG_IGN, signal.SIG_DFL, or a "
                                "callable object")
        self.default_handler = default_handler 

def testSecondInterrupt(self):
        # Can't use skipIf decorator because the signal handler may have
        # been changed after defining this method.
        if signal.getsignal(signal.SIGINT) == signal.SIG_IGN:
            self.skipTest("test requires SIGINT to not be ignored")
        result = unittest.TestResult()
        unittest.installHandler()
        unittest.registerResult(result)

        def test(result):
            pid = os.getpid()
            os.kill(pid, signal.SIGINT)
            result.breakCaught = True
            self.assertTrue(result.shouldStop)
            os.kill(pid, signal.SIGINT)
            self.fail("Second KeyboardInterrupt not raised")

        try:
            test(result)
        except KeyboardInterrupt:
            pass
        else:
            self.fail("Second KeyboardInterrupt not raised")
        self.assertTrue(result.breakCaught) 

def testHandlerReplacedButCalled(self):
        # Can't use skipIf decorator because the signal handler may have
        # been changed after defining this method.
        if signal.getsignal(signal.SIGINT) == signal.SIG_IGN:
            self.skipTest("test requires SIGINT to not be ignored")
        # If our handler has been replaced (is no longer installed) but is
        # called by the *new* handler, then it isn't safe to delay the
        # SIGINT and we should immediately delegate to the default handler
        unittest.installHandler()

        handler = signal.getsignal(signal.SIGINT)
        def new_handler(frame, signum):
            handler(frame, signum)
        signal.signal(signal.SIGINT, new_handler)

        try:
            pid = os.getpid()
            os.kill(pid, signal.SIGINT)
        except KeyboardInterrupt:
            pass
        else:
            self.fail("replaced but delegated handler doesn't raise interrupt") 

def testHandlerReplacedButCalled(self):
        # Can't use skipIf decorator because the signal handler may have
        # been changed after defining this method.
        if signal.getsignal(signal.SIGINT) == signal.SIG_IGN:
            self.skipTest("test requires SIGINT to not be ignored")
        # If our handler has been replaced (is no longer installed) but is
        # called by the *new* handler, then it isn't safe to delay the
        # SIGINT and we should immediately delegate to the default handler
        unittest.installHandler()

        handler = signal.getsignal(signal.SIGINT)
        def new_handler(frame, signum):
            handler(frame, signum)
        signal.signal(signal.SIGINT, new_handler)

        try:
            pid = os.getpid()
            os.kill(pid, signal.SIGINT)
        except KeyboardInterrupt:
            pass
        else:
            self.fail("replaced but delegated handler doesn't raise interrupt") 

def accept_invitation_and_play(server_url, auth, invitation_id, bot_cls, finished):
    # make sure this process doesn't react to interrupt signals
    signal.signal(signal.SIGTERM, signal.SIG_IGN)
    signal.signal(signal.SIGINT, signal.SIG_IGN)

    print('[{}] Accepting invitation {}.'.format(datetime.now(), invitation_id))

    server = RBCServer(server_url, auth)
    game_id = server.accept_invitation(invitation_id)

    print('[{}] Invitation {} accepted. Playing game {}.'.format(datetime.now(), invitation_id, game_id))

    try:
        play_remote_game(server_url, game_id, auth, bot_cls())
        print('[{}] Finished game {}'.format(datetime.now(), game_id))
    except:
        print('[{}] Fatal error in game {}:'.format(datetime.now(), game_id))
        traceback.print_exc()
        server.error_resign(game_id)
    finally:
        server.finish_invitation(invitation_id)
        finished.value = True 

def __init__(self, default_handler):
        self.called = False
        self.original_handler = default_handler
        if isinstance(default_handler, int):
            if default_handler == signal.SIG_DFL:
                # Pretend it's signal.default_int_handler instead.
                default_handler = signal.default_int_handler
            elif default_handler == signal.SIG_IGN:
                # Not quite the same thing as SIG_IGN, but the closest we
                # can make it: do nothing.
                def default_handler(unused_signum, unused_frame):
                    pass
            else:
                raise TypeError("expected SIGINT signal handler to be "
                                "signal.SIG_IGN, signal.SIG_DFL, or a "
                                "callable object")
        self.default_handler = default_handler 

def _import_mp():
    global Process, Queue, Pool, Event, Value, Array
    try:
        from multiprocessing import Manager, Process
        #prevent the server process created in the manager which holds Python 
        #objects and allows other processes to manipulate them using proxies
        #to interrupt on SIGINT (keyboardinterrupt) so that the communication
        #channel between subprocesses and main process is still usable after
        #ctrl+C is received in the main process.
        old=signal.signal(signal.SIGINT, signal.SIG_IGN)
        m = Manager()
        #reset it back so main process will receive a KeyboardInterrupt
        #exception on ctrl+c
        signal.signal(signal.SIGINT, old)
        Queue, Pool, Event, Value, Array = (
                m.Queue, m.Pool, m.Event, m.Value, m.Array
        )
    except ImportError:
        warn("multiprocessing module is not available, multiprocess plugin "
             "cannot be used", RuntimeWarning) 

def init_worker(num_instances, kernel_h, kernel_w, pad, stride, indices, pdfs):
    global g_num_instances
    g_num_instances = num_instances
    global g_kernel_h
    g_kernel_h = kernel_h
    global g_kernel_w
    g_kernel_w = kernel_w
    global g_pad
    g_pad = pad
    global g_stride
    g_stride = stride
    global g_indices
    g_indices = indices
    global g_pdfs
    g_pdfs = pdfs
    signal.signal(signal.SIGINT, signal.SIG_IGN)
    np.random.seed(None) 

def testSecondInterrupt(self):
        # Can't use skipIf decorator because the signal handler may have
        # been changed after defining this method.
        if signal.getsignal(signal.SIGINT) == signal.SIG_IGN:
            self.skipTest("test requires SIGINT to not be ignored")
        result = unittest.TestResult()
        unittest.installHandler()
        unittest.registerResult(result)

        def test(result):
            pid = os.getpid()
            os.kill(pid, signal.SIGINT)
            result.breakCaught = True
            self.assertTrue(result.shouldStop)
            os.kill(pid, signal.SIGINT)
            self.fail("Second KeyboardInterrupt not raised")

        try:
            test(result)
        except KeyboardInterrupt:
            pass
        else:
            self.fail("Second KeyboardInterrupt not raised")
        self.assertTrue(result.breakCaught) 

def init_worker():
    signal.signal(signal.SIGINT, signal.SIG_IGN) 

def ensure_echo_on():
    if termios:
        fd = sys.stdin
        if fd.isatty():
            attr_list = termios.tcgetattr(fd)
            if not attr_list[3] & termios.ECHO:
                attr_list[3] |= termios.ECHO
                if hasattr(signal, 'SIGTTOU'):
                    old_handler = signal.signal(signal.SIGTTOU, signal.SIG_IGN)
                else:
                    old_handler = None
                termios.tcsetattr(fd, termios.TCSANOW, attr_list)
                if old_handler is not None:
                    signal.signal(signal.SIGTTOU, old_handler) 

def test_worker_init():
  """Initialise test worker process."""
  if platform.system() != 'Windows':
    # Prevent KeyboardInterrupt error output.
    signal.signal(signal.SIGINT, signal.SIG_IGN) 

def _paramiko_tunnel(lport, rport, server, remoteip, keyfile=None, password=None):
    """Function for actually starting a paramiko tunnel, to be passed
    to multiprocessing.Process(target=this), and not called directly.
    """
    username, server, port = _split_server(server)
    client = paramiko.SSHClient()
    client.load_system_host_keys()
    client.set_missing_host_key_policy(paramiko.WarningPolicy())

    try:
        client.connect(server, port, username=username, key_filename=keyfile,
                       look_for_keys=True, password=password)
#    except paramiko.AuthenticationException:
#        if password is None:
#            password = getpass("%s@%s's password: "%(username, server))
#            client.connect(server, port, username=username, password=password)
#        else:
#            raise
    except Exception as e:
        print('*** Failed to connect to %s:%d: %r' % (server, port, e))
        sys.exit(1)

    # Don't let SIGINT kill the tunnel subprocess
    signal.signal(signal.SIGINT, signal.SIG_IGN)

    try:
        forward_tunnel(lport, remoteip, rport, client.get_transport())
    except KeyboardInterrupt:
        print('SIGINT: Port forwarding stopped cleanly')
        sys.exit(0)
    except Exception as e:
        print("Port forwarding stopped uncleanly: %s"%e)
        sys.exit(255) 

def ignore_sigint():
    handler = signal.getsignal(signal.SIGINT)
    signal.signal(signal.SIGINT, signal.SIG_IGN)
    try:
        yield
    finally:
        signal.signal(signal.SIGINT, handler) 

def save(self):
        # ignore keyboard interrupt while saving
        s = signal.signal(signal.SIGINT, signal.SIG_IGN)
        numpy.savez(self.state['prefix']+'timing.npz',
                    **self.timings)
        if self.state['overwrite']:
            self.model.save(self.state['prefix']+'model.npz')
        else:
            self.model.save(self.state['prefix'] +
                            'model%d.npz' % self.save_iter)
        cPickle.dump(self.state, open(self.state['prefix']+'state.pkl', 'w'))
        self.save_iter += 1
        signal.signal(signal.SIGINT, s)

    # FIXME 

def add_dataset(self, source, dataset_entrypoint,
                    n_workers=4, shuffle=True, DataLoader=None):
        DataLoader = (DataLoader or dataset_entrypoint._dataloader_class or
                      torch.utils.data.DataLoader)

        if len(dataset_entrypoint._datasets) == 0:
            raise ValueError('No datasets found in entrypoint')

        loaders = {}
        for k, dataset in dataset_entrypoint._datasets.items():
            N = len(dataset)
            dataset_entrypoint._dims['N_' + k] = N

            if isinstance(self.batch_size, dict):
                try:
                    self.batch_size[k]
                except KeyError:
                    self.batch_size[k] = self.batch_size_
                finally:
                    batch_size = self.batch_size[k]
            else:
                self.batch_size_ = self.batch_size
                self.batch_size = {k: self.batch_size_}
                batch_size = self.batch_size_

            loaders[k] = DataLoader(dataset, batch_size=batch_size,
                                    shuffle=shuffle, num_workers=n_workers,
                                    worker_init_fn=lambda x:
                                    signal.signal(signal.SIGINT,
                                                  signal.SIG_IGN))

        self.dims[source] = dataset_entrypoint._dims
        self.input_names[source] = dataset_entrypoint._input_names
        self.loaders[source] = loaders 

def _ignore_CTRL_C_posix():
    """Ignore CTRL+C (SIGINT)."""
    signal.signal(signal.SIGINT, signal.SIG_IGN) 

def init_worker():
    signal.signal(signal.SIGINT, signal.SIG_IGN)
    np.random.seed(None)

# Utilities for loading and saving images to/from numpy arrays 

def init_worker():
    signal.signal(signal.SIGINT, signal.SIG_IGN)
    np.random.seed(None) 

def _reload(self):
        """reload all children

        posix only
        """
        self._run_hooks('reload')

        # Reset forktimes to respawn services quickly
        self._forktimes = []
        signal.signal(signal.SIGHUP, signal.SIG_IGN)
        os.killpg(0, signal.SIGHUP)
        signal.signal(signal.SIGHUP, self._signal_catcher) 

def parallel(function, argument_list, threads):
	""" Based on: https://gist.github.com/admackin/003dd646e5fadee8b8d6 """
	import multiprocessing as mp
	import signal
	import time
	
	def init_worker():
		signal.signal(signal.SIGINT, signal.SIG_IGN)
	
	pool = mp.Pool(int(threads), init_worker)
	
	try:
		results = []
		for arguments in argument_list:
			p = pool.apply_async(function, args=arguments)
			results.append(p)
		pool.close()
		
		while True:
			if all(r.ready() for r in results):
				return [r.get() for r in results]
			time.sleep(1)

	except KeyboardInterrupt:
		pool.terminate()
		pool.join()
		sys.exit("\nKeyboardInterrupt")