memset(inst, 0, sizeof(*inst));
    inst->alt_keycode = -1;            /* this one needs _not_ to be zero */

    /* defer any child exit handling until we're ready to deal with
     * it */
    block_signal(SIGCHLD, 1);

    /*
     * SIGPIPE is not something we want to see terminating the
     * process.
     */
    block_signal(SIGPIPE, 1);

    inst->progname = argv[0];
    /*
     * Copy the original argv before letting gtk_init fiddle with
     * it. It will be required later.
     */
    {
	int i, oldargc;

	ldisc_create(&inst->cfg, inst->term, inst->back, inst->backhandle, inst);
    ldisc_send(inst->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */

    /* now we're reday to deal with the child exit handler being
     * called */
    block_signal(SIGCHLD, 0);

    /*
     * Block SIGPIPE: if we attempt Duplicate Session or similar
     * and it falls over in some way, we certainly don't want
     * SIGPIPE terminating the main pterm/PuTTY. Note that we do
     * this _after_ (at least pterm) forks off its child process,
     * since the child wants SIGPIPE handled in the usual way.
     */
    block_signal(SIGPIPE, 1);

    inst->exited = FALSE;

    gtk_main();

    return 0;
}