Python os.getpid() Examples

def __init__(self, server, port=None):
        if port is None:
            port, server = server.split('@')
            port = int(port)

        self.server   = server # server hostname for TCP connections
        self.port     = port   # server port number for TCP connections
        self.debug    = False  # show raw binary sent and received
        self.verbose  = False  # show parsed messages received
        self.oldproto = None   # will be set later if server version < VER_NEW

        self.user    = os.environ.get('USER') or ''
        self.host    = socket.gethostname()
        self.vendor  = "" # empty to start, then vendor name
        self.tty     = '/dev/pts/1'
        self.pid     = str(os.getpid())
        self.arch    = 'x64_lsb' # OS/arch ("64-bit Linux Standard Base"?)
        self.version = (11,11) # "this" lmstat version

        self.connect()

    # Lower-level public methods for specific connection and request types 

def _nsenter_args(self) -> List[str]:
        if self._namespace_to_file is None:
            raise RuntimeError('Must nsenter from inside an Unshare context')
        # The namespace FDs are O_CLOEXEC, so they are only accessible
        # through the current process.
        cur_pid = os.getpid()
        return [
            # If we happen to be in a chroot, we don't want the `nsenter`ed
            # process to end running with the original root, which is what
            # `nsenter` would do without `--root`.
            #
            # Unlike the `--root` shenanigan documented in `__enter__`, I am
            # not aware of any downsides to using `--wd=.`, and it does have
            # the advantage of presenting the target process with a
            # predictable working directory (compare: `unshare -m` changes
            # the working directory to `/`, while `unshare -p` does not).
            f'--root=/proc/{cur_pid}/fd/{self._root_fd}', '--wd=.',
            *(
                f'{ns.value}=/proc/{cur_pid}/fd/{f.fileno()}'
                    for ns, f in self._namespace_to_file.items()
            ),
        ] 

def ingest_file(file,message_size,topic,kafka_servers):
    
    logger = logging.getLogger('SPOT.INGEST.PROXY.{0}'.format(os.getpid()))
    try:        
        message = ""
        logger.info("Ingesting file: {0} process:{1}".format(file,os.getpid())) 
        with open(file,"rb") as f:
            for line in f:
                message += line
                if len(message) > message_size:
                    KafkaProducer.SendMessage(message, kafka_servers, topic, 0)
                    message = ""
            #send the last package.        
            KafkaProducer.SendMessage(message, kafka_servers, topic, 0)
        rm_file = "rm {0}".format(file)
        Util.execute_cmd(rm_file,logger)
        logger.info("File {0} has been successfully sent to Kafka Topic: {1}".format(file,topic))

    except Exception as err:        
        logger.error("There was a problem, please check the following error message:{0}".format(err.message))
        logger.error("Exception: {0}".format(err)) 

def atomic_writer(fpath, mode):
    """Atomic file writer.

    .. versionadded:: 1.12

    Context manager that ensures the file is only written if the write
    succeeds. The data is first written to a temporary file.

    :param fpath: path of file to write to.
    :type fpath: ``unicode``
    :param mode: sames as for :func:`open`
    :type mode: string

    """
    suffix = '.{}.tmp'.format(os.getpid())
    temppath = fpath + suffix
    with open(temppath, mode) as fp:
        try:
            yield fp
            os.rename(temppath, fpath)
        finally:
            try:
                os.remove(temppath)
            except (OSError, IOError):
                pass 

def testInterruptCaught(self):
        default_handler = signal.getsignal(signal.SIGINT)

        result = unittest.TestResult()
        unittest.installHandler()
        unittest.registerResult(result)

        self.assertNotEqual(signal.getsignal(signal.SIGINT), default_handler)

        def test(result):
            pid = os.getpid()
            os.kill(pid, signal.SIGINT)
            result.breakCaught = True
            self.assertTrue(result.shouldStop)

        try:
            test(result)
        except KeyboardInterrupt:
            self.fail("KeyboardInterrupt not handled")
        self.assertTrue(result.breakCaught) 

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 testTwoResults(self):
        unittest.installHandler()

        result = unittest.TestResult()
        unittest.registerResult(result)
        new_handler = signal.getsignal(signal.SIGINT)

        result2 = unittest.TestResult()
        unittest.registerResult(result2)
        self.assertEqual(signal.getsignal(signal.SIGINT), new_handler)

        result3 = unittest.TestResult()

        def test(result):
            pid = os.getpid()
            os.kill(pid, signal.SIGINT)

        try:
            test(result)
        except KeyboardInterrupt:
            self.fail("KeyboardInterrupt not handled")

        self.assertTrue(result.shouldStop)
        self.assertTrue(result2.shouldStop)
        self.assertFalse(result3.shouldStop) 

def testRemoveResult(self):
        result = unittest.TestResult()
        unittest.registerResult(result)

        unittest.installHandler()
        self.assertTrue(unittest.removeResult(result))

        # Should this raise an error instead?
        self.assertFalse(unittest.removeResult(unittest.TestResult()))

        try:
            pid = os.getpid()
            os.kill(pid, signal.SIGINT)
        except KeyboardInterrupt:
            pass

        self.assertFalse(result.shouldStop) 

def make_msgid(idstring=None):
    """Returns a string suitable for RFC 2822 compliant Message-ID, e.g:

    <[email protected]>

    Optional idstring if given is a string used to strengthen the
    uniqueness of the message id.
    """
    timeval = time.time()
    utcdate = time.strftime('%Y%m%d%H%M%S', time.gmtime(timeval))
    pid = os.getpid()
    randint = random.randrange(100000)
    if idstring is None:
        idstring = ''
    else:
        idstring = '.' + idstring
    idhost = socket.getfqdn()
    msgid = '<%s.%s.%s%[email protected]%s>' % (utcdate, pid, randint, idstring, idhost)
    return msgid



# These functions are in the standalone mimelib version only because they've
# subsequently been fixed in the latest Python versions.  We use this to worm
# around broken older Pythons. 

def _read_output(commandstring):
    """Output from successful command execution or None"""
    # Similar to os.popen(commandstring, "r").read(),
    # but without actually using os.popen because that
    # function is not usable during python bootstrap.
    # tempfile is also not available then.
    import contextlib
    try:
        import tempfile
        fp = tempfile.NamedTemporaryFile()
    except ImportError:
        fp = open("/tmp/_osx_support.%s"%(
            os.getpid(),), "w+b")

    with contextlib.closing(fp) as fp:
        cmd = "%s 2>/dev/null >'%s'" % (commandstring, fp.name)
        return fp.read().strip() if not os.system(cmd) else None 

def wait(self, timeout=None):
        """Wait for process to terminate and, if process is a children
        of os.getpid(), also return its exit code, else None.

        If the process is already terminated immediately return None
        instead of raising NoSuchProcess.

        If timeout (in seconds) is specified and process is still alive
        raise TimeoutExpired.

        To wait for multiple Process(es) use psutil.wait_procs().
        """
        if timeout is not None and not timeout >= 0:
            raise ValueError("timeout must be a positive integer")
        return self._proc.wait(timeout)


# =====================================================================
# --- Popen class
# ===================================================================== 

def print_versions():
    print
    print '-=' * 38
    print db.DB_VERSION_STRING
    print 'bsddb.db.version():   %s' % (db.version(), )
    if db.version() >= (5, 0) :
        print 'bsddb.db.full_version(): %s' %repr(db.full_version())
    print 'bsddb.db.__version__: %s' % db.__version__
    print 'bsddb.db.cvsid:       %s' % db.cvsid

    # Workaround for allowing generating an EGGs as a ZIP files.
    suffix="__"
    print 'py module:            %s' % getattr(bsddb, "__file"+suffix)
    print 'extension module:     %s' % getattr(bsddb, "__file"+suffix)

    print 'python version:       %s' % sys.version
    print 'My pid:               %s' % os.getpid()
    print '-=' * 38 

def _create_tmp(self):
        """Create a file in the tmp subdirectory and open and return it."""
        now = time.time()
        hostname = socket.gethostname()
        if '/' in hostname:
            hostname = hostname.replace('/', r'\057')
        if ':' in hostname:
            hostname = hostname.replace(':', r'\072')
        uniq = "%s.M%sP%sQ%s.%s" % (int(now), int(now % 1 * 1e6), os.getpid(),
                                    Maildir._count, hostname)
        path = os.path.join(self._path, 'tmp', uniq)
        try:
            os.stat(path)
        except OSError, e:
            if e.errno == errno.ENOENT:
                Maildir._count += 1
                try:
                    return _create_carefully(path)
                except OSError, e:
                    if e.errno != errno.EEXIST:
                        raise 

def test_failed_child_execute_fd_leak(self):
        """Test for the fork() failure fd leak reported in issue16327."""
        fd_directory = '/proc/%d/fd' % os.getpid()
        fds_before_popen = os.listdir(fd_directory)
        with self.assertRaises(PopenTestException):
            PopenExecuteChildRaises(
                    [sys.executable, '-c', 'pass'], stdin=subprocess.PIPE,
                    stdout=subprocess.PIPE, stderr=subprocess.PIPE)

        # NOTE: This test doesn't verify that the real _execute_child
        # does not close the file descriptors itself on the way out
        # during an exception.  Code inspection has confirmed that.

        fds_after_exception = os.listdir(fd_directory)
        self.assertEqual(fds_before_popen, fds_after_exception)


# context manager 

def test_main():
    from bsddb import db
    from bsddb.test import test_all
    test_all.set_test_path_prefix(os.path.join(tempfile.gettempdir(),
                                 'z-test_bsddb3-%s' %
                                 os.getpid()))
    # Please leave this print in, having this show up in the buildbots
    # makes diagnosing problems a lot easier.
    print >>sys.stderr, db.DB_VERSION_STRING
    print >>sys.stderr, 'Test path prefix: ', test_all.get_test_path_prefix()
    try:
        run_unittest(test_all.suite(module_prefix='bsddb.test.',
                                    timing_check=TimingCheck))
    finally:
        # The only reason to remove db_home is in case if there is an old
        # one lying around.  This might be by a different user, so just
        # ignore errors.  We should always make a unique name now.
        try:
            test_all.remove_test_path_directory()
        except:
            pass 

def free(self, block):
        # free a block returned by malloc()
        # Since free() can be called asynchronously by the GC, it could happen
        # that it's called while self._lock is held: in that case,
        # self._lock.acquire() would deadlock (issue #12352). To avoid that, a
        # trylock is used instead, and if the lock can't be acquired
        # immediately, the block is added to a list of blocks to be freed
        # synchronously sometimes later from malloc() or free(), by calling
        # _free_pending_blocks() (appending and retrieving from a list is not
        # strictly thread-safe but under cPython it's atomic thanks to the GIL).
        assert os.getpid() == self._lastpid
        if not self._lock.acquire(False):
            # can't acquire the lock right now, add the block to the list of
            # pending blocks to free
            self._pending_free_blocks.append(block)
        else:
            # we hold the lock
            try:
                self._free_pending_blocks()
                self._allocated_blocks.remove(block)
                self._free(block)
            finally:
                self._lock.release() 

def __init__(self, maxsize=0):
        if maxsize <= 0:
            maxsize = _multiprocessing.SemLock.SEM_VALUE_MAX
        self._maxsize = maxsize
        self._reader, self._writer = Pipe(duplex=False)
        self._rlock = Lock()
        self._opid = os.getpid()
        if sys.platform == 'win32':
            self._wlock = None
        else:
            self._wlock = Lock()
        self._sem = BoundedSemaphore(maxsize)

        self._after_fork()

        if sys.platform != 'win32':
            register_after_fork(self, Queue._after_fork) 

def __call__(self, wr=None):
        '''
        Run the callback unless it has already been called or cancelled
        '''
        try:
            del _finalizer_registry[self._key]
        except KeyError:
            sub_debug('finalizer no longer registered')
        else:
            if self._pid != os.getpid():
                sub_debug('finalizer ignored because different process')
                res = None
            else:
                sub_debug('finalizer calling %s with args %s and kwargs %s',
                          self._callback, self._args, self._kwargs)
                res = self._callback(*self._args, **self._kwargs)
            self._weakref = self._callback = self._args = \
                            self._kwargs = self._key = None
            return res 

def start(self):
        '''
        Start child process
        '''
        assert self._popen is None, 'cannot start a process twice'
        assert self._parent_pid == os.getpid(), \
               'can only start a process object created by current process'
        assert not _current_process._daemonic, \
               'daemonic processes are not allowed to have children'
        _cleanup()
        if self._Popen is not None:
            Popen = self._Popen
        else:
            from .forking import Popen
        self._popen = Popen(self)
        _current_process._children.add(self) 

def __repr__(self):
        if self is _current_process:
            status = 'started'
        elif self._parent_pid != os.getpid():
            status = 'unknown'
        elif self._popen is None:
            status = 'initial'
        else:
            if self._popen.poll() is not None:
                status = self.exitcode
            else:
                status = 'started'

        if type(status) is int:
            if status == 0:
                status = 'stopped'
            else:
                status = 'stopped[%s]' % _exitcode_to_name.get(status, status)

        return '<%s(%s, %s%s)>' % (type(self).__name__, self._name,
                                   status, self._daemonic and ' daemon' or '')

    ## 

def atomic_writer(fpath, mode):
    """Atomic file writer.

    .. versionadded:: 1.12

    Context manager that ensures the file is only written if the write
    succeeds. The data is first written to a temporary file.

    :param fpath: path of file to write to.
    :type fpath: ``unicode``
    :param mode: sames as for :func:`open`
    :type mode: string

    """
    suffix = '.{}.tmp'.format(os.getpid())
    temppath = fpath + suffix
    with open(temppath, mode) as fp:
        try:
            yield fp
            os.rename(temppath, fpath)
        finally:
            try:
                os.remove(temppath)
            except (OSError, IOError):
                pass 

def _check_alive(self):
        # If our parent changed then we shut down.
        pid = os.getpid()
        try:
            while self.alive:
                self.notify()

                req_count = sum(
                    self.servers[srv]["requests_count"] for srv in self.servers
                )
                if self.max_requests and req_count > self.max_requests:
                    self.alive = False
                    self.log.info("Max requests exceeded, shutting down: %s",
                                  self)
                elif pid == os.getpid() and self.ppid != os.getppid():
                    self.alive = False
                    self.log.info("Parent changed, shutting down: %s", self)
                else:
                    await asyncio.sleep(1.0, loop=self.loop)
        except (Exception, BaseException, GeneratorExit, KeyboardInterrupt):
            pass 

def normalize(img_path, images, images_set, parameters):
    """
    Function that performs the normalization of a feature vector.
    """
    
    print "Normalizer: EXAMPLE"
    
    #Get the list of classes and the feature vector of the img_path
    img_classes = images[img_path][0]
    img_fv = images[img_path][1][0]
    
    print "\tFeature vector of image", img_path, \
          "being normalized by process", os.getpid()
    
    # Performs the normalization ---------------------------------------------
    
    #-------------------------------------------------------------------------
    
    return img_path, len(img_classes), img_classes, fv_norm 

def write_pid_to_pidfile(pidfile_path):
    """ Write the PID in the named PID file.

        Get the numeric process ID (“PID”) of the current process
        and write it to the named file as a line of text.

        """
    open_flags = (os.O_CREAT | os.O_EXCL | os.O_WRONLY)
    open_mode = 0o644
    pidfile_fd = os.open(pidfile_path, open_flags, open_mode)
    pidfile = os.fdopen(pidfile_fd, 'w')

    # According to the FHS 2.3 section on PID files in /var/run:
    #
    #   The file must consist of the process identifier in
    #   ASCII-encoded decimal, followed by a newline character. For
    #   example, if crond was process number 25, /var/run/crond.pid
    #   would contain three characters: two, five, and newline.

    pid = os.getpid()
    pidfile.write("%s\n" % pid)
    pidfile.close() 

def save(self):
        """Save the collected coverage data to the data file."""
        data_suffix = self.data_suffix
        if data_suffix is True:
            # If data_suffix was a simple true value, then make a suffix with
            # plenty of distinguishing information.  We do this here in
            # `save()` at the last minute so that the pid will be correct even
            # if the process forks.
            extra = ""
            if _TEST_NAME_FILE:
                f = open(_TEST_NAME_FILE)
                test_name = f.read()
                f.close()
                extra = "." + test_name
            data_suffix = "%s%s.%s.%06d" % (
                socket.gethostname(), extra, os.getpid(),
                random.randint(0, 999999)
                )

        self._harvest_data()
        self.data.write(suffix=data_suffix) 

def create(self, pid):
        oldpid = self.validate()
        if oldpid:
            if oldpid == os.getpid():
                return
            msg = "Already running on PID %s (or pid file '%s' is stale)"
            raise RuntimeError(msg % (oldpid, self.fname))

        self.pid = pid

        # Write pidfile
        fdir = os.path.dirname(self.fname)
        if fdir and not os.path.isdir(fdir):
            raise RuntimeError("%s doesn't exist. Can't create pidfile." % fdir)
        fd, fname = tempfile.mkstemp(dir=fdir)
        os.write(fd, ("%s\n" % self.pid).encode('utf-8'))
        if self.fname:
            os.rename(fname, self.fname)
        else:
            self.fname = fname
        os.close(fd)

        # set permissions to -rw-r--r--
        os.chmod(self.fname, 420) 

def receive(self, from_file):
        # At present, we always have an empty wrapper dir to receive into.
        # If this changes, we could make a tempdir inside `parent_fd`.
        with open_fd(
            os.path.dirname(self.path()), os.O_RDONLY | os.O_DIRECTORY,
        ) as parent_fd:
            wrapper_dir_contents = os.listdir(parent_fd)
            assert wrapper_dir_contents == [], wrapper_dir_contents
            try:
                with self.popen_as_root([
                    'btrfs', 'receive',
                    # Future: If we get `pass_fds` support, use `/proc/self/fd'
                    Path('/proc') / str(os.getpid()) / 'fd' / str(parent_fd),
                ], _subvol_exists=False, stdin=from_file):
                    yield
            finally:
                received_names = os.listdir(parent_fd)
                assert len(received_names) <= 1, received_names
                if received_names:
                    os.rename(
                        received_names[0],
                        os.path.basename(self.path()),
                        src_dir_fd=parent_fd,
                        dst_dir_fd=parent_fd,
                    )
                    # This may be a **partially received** subvol.  If these
                    # semantics turn out to be broken for our purposes, we
                    # can try to clean up the subvolume on error instead,
                    # but at present it seems easier to leak it, and let the
                    # GC code delete it later.
                    self._exists = True 

def rng(self):
        cur_pid = _os.getpid()
        if cur_pid != getattr(self, '_rng_pid', None):
            self._rng = _Random()
            self._rng_pid = cur_pid
        return self._rng 

def testInstallHandler(self):
        default_handler = signal.getsignal(signal.SIGINT)
        unittest.installHandler()
        self.assertNotEqual(signal.getsignal(signal.SIGINT), default_handler)

        try:
            pid = os.getpid()
            os.kill(pid, signal.SIGINT)
        except KeyboardInterrupt:
            self.fail("KeyboardInterrupt not handled")

        self.assertTrue(unittest.signals._interrupt_handler.called) 

def choose_boundary():
    """Return a string usable as a multipart boundary.

    The string chosen is unique within a single program run, and
    incorporates the user id (if available), process id (if available),
    and current time.  So it's very unlikely the returned string appears
    in message text, but there's no guarantee.

    The boundary contains dots so you have to quote it in the header."""

    global _prefix
    import time
    if _prefix is None:
        import socket
        try:
            hostid = socket.gethostbyname(socket.gethostname())
        except socket.gaierror:
            hostid = '127.0.0.1'
        try:
            uid = repr(os.getuid())
        except AttributeError:
            uid = '1'
        try:
            pid = repr(os.getpid())
        except AttributeError:
            pid = '1'
        _prefix = hostid + '.' + uid + '.' + pid
    return "%s.%.3f.%d" % (_prefix, time.time(), _get_next_counter())


# Subroutines for decoding some common content-transfer-types 

def get_new_path(name) :
    get_new_path.mutex.acquire()
    try :
        import os
        path=os.path.join(get_new_path.prefix,
                name+"_"+str(os.getpid())+"_"+str(get_new_path.num))
        get_new_path.num+=1
    finally :
        get_new_path.mutex.release()
    return path 

def _create_temporary(path):
    """Create a temp file based on path and open for reading and writing."""
    return _create_carefully('%s.%s.%s.%s' % (path, int(time.time()),
                                              socket.gethostname(),
                                              os.getpid())) 

def test_communicate_pipe_fd_leak(self):
        fd_directory = '/proc/%d/fd' % os.getpid()
        num_fds_before_popen = len(os.listdir(fd_directory))
        p = subprocess.Popen([sys.executable, "-c", "print()"],
                             stdout=subprocess.PIPE)
        p.communicate()
        num_fds_after_communicate = len(os.listdir(fd_directory))
        del p
        num_fds_after_destruction = len(os.listdir(fd_directory))
        self.assertEqual(num_fds_before_popen, num_fds_after_destruction)
        self.assertEqual(num_fds_before_popen, num_fds_after_communicate) 

def f(self, id):
        while not self.stop:
            self.alive[id] = os.getpid()
            try:
                time.sleep(SHORTSLEEP)
            except IOError:
                pass 

def test_current(self):
        if self.TYPE == 'threads':
            self.skipTest('test not appropriate for {}'.format(self.TYPE))

        current = self.current_process()
        authkey = current.authkey

        self.assertTrue(current.is_alive())
        self.assertTrue(not current.daemon)
        self.assertIsInstance(authkey, bytes)
        self.assertTrue(len(authkey) > 0)
        self.assertEqual(current.ident, os.getpid())
        self.assertEqual(current.exitcode, None) 

def cache(self):
        pid = os.getpid()
        # There are no race conditions since fork keeps only the running thread
        if pid != self._pid:
            self._pid = pid
            self._cache = []
        return self._cache 

def __init__(self, size):
            self.size = size
            self.name = 'pym-%d-%d' % (os.getpid(), Arena._counter.next())
            self.buffer = mmap.mmap(-1, self.size, tagname=self.name)
            assert win32.GetLastError() == 0, 'tagname already in use'
            self._state = (self.size, self.name) 

def __init__(self, size=mmap.PAGESIZE):
        self._lastpid = os.getpid()
        self._lock = threading.Lock()
        self._size = size
        self._lengths = []
        self._len_to_seq = {}
        self._start_to_block = {}
        self._stop_to_block = {}
        self._allocated_blocks = set()
        self._arenas = []
        # list of pending blocks to free - see free() comment below
        self._pending_free_blocks = [] 

def rebuild_handle(pickled_data):
    address, handle, inherited = pickled_data
    if inherited:
        return handle
    sub_debug('rebuilding handle %d', handle)
    conn = Client(address, authkey=current_process().authkey)
    conn.send((handle, os.getpid()))
    new_handle = recv_handle(conn)
    conn.close()
    return new_handle

#
# Register `_multiprocessing.Connection` with `ForkingPickler`
# 

def __init__(self, obj, callback, args=(), kwargs=None, exitpriority=None):
        assert exitpriority is None or type(exitpriority) is int

        if obj is not None:
            self._weakref = weakref.ref(obj, self)
        else:
            assert exitpriority is not None

        self._callback = callback
        self._args = args
        self._kwargs = kwargs or {}
        self._key = (exitpriority, _finalizer_counter.next())
        self._pid = os.getpid()

        _finalizer_registry[self._key] = self 

def arbitrary_address(family):
    '''
    Return an arbitrary free address for the given family
    '''
    if family == 'AF_INET':
        return ('localhost', 0)
    elif family == 'AF_UNIX':
        return tempfile.mktemp(prefix='listener-', dir=get_temp_dir())
    elif family == 'AF_PIPE':
        return tempfile.mktemp(prefix=r'\\.\pipe\pyc-%d-%d-' %
                               (os.getpid(), _mmap_counter.next()), dir="")
    else:
        raise ValueError('unrecognized family') 

def join(self, timeout=None):
        '''
        Wait until child process terminates
        '''
        assert self._parent_pid == os.getpid(), 'can only join a child process'
        assert self._popen is not None, 'can only join a started process'
        res = self._popen.wait(timeout)
        if res is not None:
            _current_process._children.discard(self) 

def is_alive(self):
        '''
        Return whether process is alive
        '''
        if self is _current_process:
            return True
        assert self._parent_pid == os.getpid(), 'can only test a child process'
        if self._popen is None:
            return False
        self._popen.poll()
        return self._popen.returncode is None 

def ident(self):
        '''
        Return identifier (PID) of process or `None` if it has yet to start
        '''
        if self is _current_process:
            return os.getpid()
        else:
            return self._popen and self._popen.pid 

def getMemUsageOfCurProcess_MiB(field='rss'):
    # return the memory usage in MB
    process = psutil.Process(os.getpid())
    mem = getattr(process.memory_info(), field)
    mem_MiB = mem / float(2 ** 20)
    return mem_MiB 

def run(self) -> None:
        logger = get_logger(0)

        logger.info("Started HID-%s pid=%d", self.__name, os.getpid())
        signal.signal(signal.SIGINT, signal.SIG_IGN)
        setproctitle.setproctitle(f"kvmd/hid-{self.__name}: {setproctitle.getproctitle()}")

        while not self.__stop_event.is_set():
            try:
                while not self.__stop_event.is_set():
                    passed = 0
                    try:
                        event: BaseEvent = self.__events_queue.get(timeout=0.05)
                    except queue.Empty:
                        if passed >= 20:  # 20 * 0.05 = 1 sec
                            self._ensure_device()  # Check device
                            passed = 0
                        else:
                            passed += 1
                    else:
                        self._process_event(event)
                        passed = 0
            except Exception:
                logger.exception("Unexpected HID-%s error", self.__name)
                self._close_device()
            finally:
                time.sleep(1)

        self._close_device() 

def run(self) -> None:  # pylint: disable=too-many-branches
        logger = get_logger(0)

        logger.info("Started HID pid=%d", os.getpid())
        signal.signal(signal.SIGINT, signal.SIG_IGN)
        setproctitle.setproctitle(f"kvmd/hid: {setproctitle.getproctitle()}")

        while not self.__stop_event.is_set():
            try:
                with self.__get_serial() as tty:
                    passed = 0
                    while not (self.__stop_event.is_set() and self.__events_queue.qsize() == 0):
                        try:
                            event: _BaseEvent = self.__events_queue.get(timeout=0.05)
                        except queue.Empty:
                            if passed >= 20:  # 20 * 0.05 = 1 sec
                                self.__process_command(tty, b"\x01\x00\x00\x00\x00")  # Ping
                                passed = 0
                            else:
                                passed += 1
                        else:
                            self.__process_command(tty, event.make_command())
                            passed = 0

            except serial.SerialException as err:
                if err.errno == errno.ENOENT:
                    logger.error("Missing HID serial device: %s", self.__device_path)
                else:
                    logger.exception("Unexpected HID error")

            except Exception:
                logger.exception("Unexpected HID error")

            finally:
                time.sleep(1) 

def __init__(self, tornado_app, sockets):
        super(TornadoProcess, self).__init__()

        self._http_server = None
        self._parent_pid = os.getpid()
        self._ready = multiprocessing.Value(ctypes.c_bool, False)
        self._sockets = sockets
        self._tornado_app = tornado_app

        self.context = self._tornado_app.settings['context']
        self.http_server = None
        self.logger = logging.getLogger(
            "{:s}.{:s}".format(__name__, self.__class__.__name__)) 

def initialize(self):
        """
        Initialize instance attributes. You can override this method in
        the subclasses.
        """
        self.main_pid = os.getpid()
        self.processes.extend(self.init_service_processes())
        self.processes.extend(self.init_tornado_workers()) 

def sigusr1_handler(self, unused_signum, unused_frame):
        """
        Handle SIGUSR1 signal. Call function which is defined in the
        **settings.SIGUSR1_HANDLER**. If main process, forward the
        signal to all child processes.
        """
        for process in self.processes:
            if process.pid and os.getpid() == self.main_pid:
                try:
                    os.kill(process.pid, signal.SIGUSR1)
                except ProcessLookupError:
                    pass
        if self._sigusr1_handler_func is not None:
            self._sigusr1_handler_func(self.context)