gio:menu-item-link (item link)

item -- a g:menu-item object
link -- a string with the type of link to establish or unset
model -- a g:menu-model object to link to, or nil to unset

The g:menu-item-link function queries the named link on item. The (setf g:menu-item-link) function creates a link from item to model if not nil, or unsets it.

Links are used to establish a relationship between a particular menu item and another menu. For example, the "submenu" attribute is used to associate a submenu with a particular menu item, and the "section" attribute is used to create a section. Other types of link can be used, but there is no guarantee that clients will be able to make sense of them. Link types are restricted to lowercase characters, numbers and '-'. Furthermore, the names must begin with a lowercase character, must not end with a '-', and must not contain consecutive dashes.