If the data set allocation was dynamic and had the XTIOT (S99TIOEX) or nocapture (S99ACUCB) option, then this field contains zeroes. You can use DEBXTNP, DEBXDSAB and DSABTIOT to get the TIOT or XTIOT entry address. If the allocation was not dynamic or did not have the XTIOT or nocapture option, this field is unsigned (16-bit) offset in the TIOT to the entry.

An entry in the TIOT or XTIOT is mapped by the IEFTIOT1 macro.