READLINE_6.3 {
    rl_change_environment;
    rl_clear_history;
    rl_executing_key;
    rl_executing_keyseq;
    rl_filename_stat_hook;
    rl_history_substr_search_backward;
    rl_history_substr_search_forward;
    rl_input_available_hook;
    rl_print_last_kbd_macro;
    rl_signal_event_hook;
};