Python winerror.ERROR_ALREADY_EXISTS Examples

def __acquire(self):
        '''
        Attempts to acquire the mutex
        @raise MutexAlreadyAcquired
        '''

        mutex = win32event.CreateMutex(None, 1, self.MUTEX_NAME)
        if win32api.GetLastError() == winerror.ERROR_ALREADY_EXISTS:
            raise MutexAlreadyAcquired()

        return mutex


# ================================================================
# = MutexAlreadyAcquired Exception Class
# =============================================================== 

def testLongLongPathNames(self):
        # We need filename where the FQN is > 256 - simplest way is to create a
        # 250 character directory in the cwd (except - cwd may be on a drive
        # not supporting \\\\?\\ (eg, network share) - so use temp.
        import win32file
        basename = "a" * 250
        # but we need to ensure we use the 'long' version of the
        # temp dir for later comparison.
        long_temp_dir = win32api.GetLongPathNameW(tempfile.gettempdir())
        fname = "\\\\?\\" + os.path.join(long_temp_dir, basename)
        try:
            win32file.CreateDirectoryW(fname, None)
        except win32api.error, details:
            if details.winerror!=winerror.ERROR_ALREADY_EXISTS:
                raise 

def create(self):
        obtain_mutex = 1
        mutex = win32event.CreateMutex(None, obtain_mutex, app_name)

        # prevent the PyHANDLE from going out of scope, ints are fine
        self.mutex = int(mutex)
        mutex.Detach()

        lasterror = win32api.GetLastError()
        
        if lasterror == winerror.ERROR_ALREADY_EXISTS:
            takeover = 0

            try:
                # if the mutex already exists, discover which port to connect to.
                # if something goes wrong with that, tell us to take over the
                # role of master
                takeover = self.discover_sic_socket()
            except:
                pass
            
            if not takeover:
                raise BTFailure(_("Global mutex already created."))

        self.master = 1

        # lazy free port code
        port_limit = 50000
        while self.port < port_limit:
            try:
                controlsocket = self.rawserver.create_serversocket(self.port,
                                                                   '127.0.0.1')
                self.controlsocket = controlsocket
                break
            except socket.error, e:
                self.port += 1 

def IsAnotherInstanceRunning(self):
        return winerror.ERROR_ALREADY_EXISTS == self.lasterror 

def aleradyrunning(self):
        return (self.lasterror == ERROR_ALREADY_EXISTS)