What to do if number of menu items exceeds screenspace?

Currently I have an application that is creating menu items using glut. The menu items are being created by glutAddMenuEntry. The number of items being added is dynamic based on the data being processed. In some cases the number of menu items exceeds the screen height and the lower half of the menu is being displayed without any access to the upper items on the menu. How would one be able to detect whether the number of menu items exceeds screen space? This would allow the menu to be split into multiple menus so all items could be accessed. Or, how does one access the menu items at the top, which are currently unaccessable?

Cheers -

you can put a menu with submenus, and store options there. It’s not a good idea to have 1 screen long menu. Organise your objects into groups in submenus.