Inside Macintosh: Mac OS 8 Toolbox Reference /

Chapter 5 - Menu Manager Reference / Menu Manager Functions

Manipulating and Accessing Menu Item Characteristics /

SetItemMark

NOT RECOMMENDED WITH THE APPEARANCE MANAGER

When the Appearance Manager is available, you should call SetMenuItemHierarchicalID instead of SetItemMark to set the menu ID of a menu item's submenu. However, you can still use SetItemMark to set the mark of a menu item.