[ KeyDelay tenths  key done ix;
    glk($00D2, gg_mainwin); ! request_char_event
    glk($00D6, tenths*100); ! request_timer_events
    while (~~done) {
        glk($00C0, gg_event); ! select
        ix = HandleGlkEvent(gg_event, 1, gg_arguments);
        if (ix == 2) {
            key = gg_arguments-->0;
            done = true;
        }
        else if (ix >= 0 && gg_event-->0 == 1 or 2) {
            key = gg_event-->2;
            done = true;
        }
    }
    glk($00D3, gg_mainwin); ! cancel_char_event
    glk($00D6, 0); ! request_timer_events
    return key;
];