utils.py 文件源码

def is_special_file(cls, filename):
        """Checks to see if a file is a special UNIX file.

        It checks if the file is a character special device, block special
        device, FIFO, or socket.

        :param filename: Name of the file

        :returns: True if the file is a special file. False, if is not.
        """
        # If it does not exist, it must be a new file so it cannot be
        # a special file.
        if not os.path.exists(filename):
            return False
        mode = os.stat(filename).st_mode
        # Character special device.
        if stat.S_ISCHR(mode):
            return True
        # Block special device
        if stat.S_ISBLK(mode):
            return True
        # Named pipe / FIFO
        if stat.S_ISFIFO(mode):
            return True
        # Socket.
        if stat.S_ISSOCK(mode):
            return True
        return False