The function set_menu_format sets the maximum display size of the given menu. If this size is too small to display all menu items, the menu will be made scrollable. If this size is larger than the menus subwindow and the subwindow is too small to display all menu items, post_menu() will fail.
The default format is 16 rows, 1 column. Calling set_menu_format with a null menu pointer will change this default. A zero row or column argument to set_menu_format is interpreted as a request not to change the current value.
The function menu_format returns the maximum-size constraints for the given menu into the storage addressed by rows and cols.
These routines returns one of the following: