WindowsScriptLock.py

class SingletonLock(object):
	"""docstring for SingletonLock"""
	LOCK_EX = win32con.LOCKFILE_EXCLUSIVE_LOCK
	LOCK_NB = win32con.LOCKFILE_FAIL_IMMEDIATELY
	_overlapped = pywintypes.OVERLAPPED()

	def __init__(self, lockfile,flag):
		super(SingletonLock, self).__init__()
		self._lockfile_ = open(lockfile,"w")
		self._hfile_ = win32file._get_osfhandle(self._lockfile_.fileno())
		self._flag_ = flag

	def __enter__(self):
		win32file.LockFileEx(self._hfile_, self._flag_, 0, long(0xffff0000),self._overlapped)
		return self._lockfile_

	def __exit__(self, exec_type, exec_value, exce_traceback):
		try:
			win32file.UnlockFileEx(self._hfile_, 0, long(0xffff0000), self._overlapped)
			self._lockfile_.close()
			pass
		except Exception, e:
			return False
		else:
			return True