You can put a window on the screen by calling the function wn_up(), and take the window off the screen by calling wn_dn(). This is the simplest method of using a window. If you want the window to stay on the screen until the user presses a key, you can call the keyboard function ki() to wait for a keystroke after calling wn_up().
If you want the user to be able to scroll through a virtual window or a memory file, or if you want to simplify the process of displaying a window and waiting for user input, you should process the window instead of merely displaying it.
