To define a menu key in a character-based environment, assign the edit-action "Menu" to a key with the KEYSTROKE variable in your COBOL configuration file. For example, to make the <F1> key a menu key, place this line into your configuration file:
KEYSTROKE Edit=Menu k1
Keys and their key codes (such as k1) are listed in Chapter 4, section 4.3.2.3, of the User's Guide (Book 1).
You can also define a menu key within your program with SET ENVIRONMENT. For example,
SET ENVIRONMENT "KEYSTROKE"
TO "Edit=Menu k1"
Once a menu is active, the user can:
use the arrow keys to move the highlight
select an item with the Spacebar or the Return key
jump to an item and select it by typing its key letter
use the Escape key, along with any program-defined menu keys, to cancel a menu
or a submenu