io.py 文件源码

def touch(self, path, mode=0o644, dir_fd=None, **kwargs):
        """Create an empty file with selected permissions.

        Args:
            path (str): File path.
            mode (:obj:`int`, optional): File access mode. Defaults to 0o644.
            dir_fd (optional): If set, it should be a file descriptor open to a
                directory and path should then be relative to that directory.
                Defaults to None.
            **kwargs: Arbitrary keyword arguments.
        """
        flags = os.O_CREAT | os.O_APPEND
        with os.fdopen(
                os.open(path, flags=flags, mode=mode, dir_fd=dir_fd) ) as f:
            os.utime(
                f.fileno() if os.utime in os.supports_fd else path,
                dir_fd=None if os.supports_fd else dir_fd,
                **kwargs )