io.py 文件源码

def blocking(self):
        '''
        Allow temporary access to the underlying file in blocking mode
        '''
        if self._buffer:
            raise IOError('There is unread buffered data.')
        try:
            os.set_blocking(int(self._fileno), True)
            yield self._file
        finally:
            os.set_blocking(int(self._fileno), False)