Returns the most specific instantiatable prerequisite of an interface type. If the interface type has no instantiatable prerequisite, %G_TYPE_INVALID is returned.
See g_type_interface_add_prerequisite() for more information about prerequisites.
an interface type
the instantiatable prerequisite type or %G_TYPE_INVALID if none
2.68
See Implementation
Returns the most specific instantiatable prerequisite of an interface type. If the interface type has no instantiatable prerequisite, %G_TYPE_INVALID is returned.
See g_type_interface_add_prerequisite() for more information about prerequisites.