def callback_read_char(self):
        u'''Reads a character and informs the readline callback interface when a line is received'''
        if self.keyboard_poll():
            line = self.get_line_buffer() + u'\n'
            # however there is another newline added by
            # self.mode.readline_setup(prompt) which is called by callback_handler_install
            # this differs from GNU readline
            self.add_history(self.mode.l_buffer)
            # TADA:
            self.callback(line)
u'''Reads a character and informs the readline callback interface when a line is received