Signature:

      SUBROUTINE h5rget_object_type_f(loc_id, ref_type, ref, obj_type, hdferr)
        INTEGER(HID_T), INTENT(IN)  :: loc_id
        INTEGER       , INTENT(IN)  :: ref_type
        TYPE(C_PTR)   , INTENT(IN)  :: ref
        INTEGER       , INTENT(OUT) :: obj_type
        INTEGER       , INTENT(OUT) :: hdferr

Inputs:

      loc_id   - Identifier for the dataset containing the reference or
                 for the group that dataset is in.
      ref_type - Type of reference to query.
      ref      - Reference to query.

Outputs:

      obj_type - Type of referenced object.
                   H5G_UNKNOWN_F
                   H5G_LINK_F
                   H5G_GROUP_F
                   H5G_DATASET_F
                   H5G_TYPE_F

      hdferr   - Returns 0 if successful and -1 if fails