Section 11,43: IEOR

 IEOR (integer, integer)

 A function that performs an exclusive OR of the arguments on a bit
 by bit basis (bit exclusive OR).

 +------+---------+----------+------------+-------------+        
 | Args | Generic | Specific |  Argument  | Result Type |
 +------+---------+----------+------------+-------------+
 |  2   | IEOR    |   --     | INTEGER*1  | INTEGER*1   |
 |      |         | IIEOR    | INTEGER*2  | INTEGER*2   |
 |      |         | JIEOR    | INTEGER*4  | INTEGER*4   |
 |      |see note | KIEOR    | INTEGER*8  | INTEGER*8   |
 +------+---------+----------+------------+-------------+

 NOTE: KIEOR is only available on AXP systems.