add update system

src/main.c

@@ -1,4 +1,14 @@
 #include <ncurses.h>
+#include <string.h>
+
+void update(WINDOW *win)
+{
+        int win_y, win_x;
+        char message[] = "test";
+        getmaxyx(win, win_y, win_x);
+        mvwprintw(win, win_y/2, win_x/2 - strlen(message)/2, "%s", message);
+        wrefresh(win);
+}
 
 int main()
 {	
@@ -23,7 +33,13 @@ int main()
         wrefresh(top_win);
         wrefresh(bottom_win);
 
-        getch();
+        int ch = ERR;
+        while(ch == ERR)
+        {
+                update(top_win);
+                update(bottom_win);
+                ch = getch();
+        };
 
         delwin(top_win);
         delwin(bottom_win);