Loads a single object from a datafile index.


DATAFILE *load_datafile_object_indexed(const DATAFILE_INDEX *index, int item)
This loads a single object, using the index created previously with create_datafile_index. See create_datafile_index for an example.
Returns a pointer to a single DATAFILE element whose "dat" member points to the object, or NULL if the object could not be loaded.