IBM DOS/VS COBOL has four special registers associated with the SORT statement. When in the IBM DOS/VS compatibility mode, ACUCOBOL-GT treats these as dummy registers, as though they had been declared at the beginning of the WORKING-STORAGE section as follows:
77 SORT-FILE-SIZE PICTURE S9(8) USAGE COMP-4 VALUE 0. 77 SORT-CORE-SIZE PICTURE S9(8) USAGE COMP-4 VALUE 0. 77 SORT-MODE-SIZE PICTURE S9(5) USAGE COMP-4 VALUE 0. 77 SORT-RETURN PICTURE S9(4) USAGE COMP-4 VALUE 0.
These registers cannot be used as operands of ACCEPT or DISPLAY statements (as in IBM DOS/VS COBOL), but values can be moved to and from them.