A set of group code ranges permits objects to directly specify references to other objects within the same drawing/DXF file. Four ranges are provided for the four types of reference handles that you can specify:
These handle types are manifested as entity names in AutoLISP ® , as ads_name values in ObjectARX ® and as like-named classes derived from ObjectARX. These values are always maintained in insert, xref, and wblock operations such that references between objects in a set being copied are updated to point to the copied objects, while references to other objects remain unchanged.
Also, a group code range for “arbitrary” handles is defined to allow convenient storage of handle values that are not converted to entity names and then translated in insert, xref, or wblock.