Make curses completely inactivated in quiet mode and do not update curses code in wakeup thread when curses is inactive.

main.c

@@ -1706,6 +1706,7 @@ static void *wakeup_thread(void *userdata)
 
 		hashmeter(-1, &zero_tv, 0);
 
+		if (curses_active) {
 			pthread_mutex_lock(&curses_lock);
 			getmaxyx(mainwin, y, x);
 			getmaxyx(logwin, logy, logx);
@@ -1716,6 +1717,7 @@ static void *wakeup_thread(void *userdata)
 			redrawwin(logwin);
 			redrawwin(statuswin);
 			pthread_mutex_unlock(&curses_lock);
+		}
 
 		if (unlikely(work_restart[stage_thr_id].restart)) {
 			restart_threads(false);
@@ -1976,6 +1978,7 @@ int main (int argc, char *argv[])
 	pthread_mutex_unlock(&hash_lock);
 
 	/* Set up the ncurses interface */
+	if (!opt_quiet) {
 		mainwin = initscr();
 		statuswin = newwin(logstart, 80, 0, 0);
 		getmaxyx(mainwin, y, x);
@@ -1987,6 +1990,7 @@ int main (int argc, char *argv[])
 		curses_active = true;
 		for (i = 0; i < mining_threads; i++)
 			print_status(i);
+	}
 
 	/* Now that everything's ready put enough work in the queue */
 	for (i = 0; i < opt_queue + mining_threads; i++) {
@@ -2006,10 +2010,12 @@ int main (int argc, char *argv[])
 
 	applog(LOG_INFO, "workio thread dead, exiting.");
 
+	if (curses_active) {
 		delwin(logwin);
 		delwin(statuswin);
 		endwin();
 		refresh();
+	}
 
 	return 0;
 }