COBOL Manual for TNS/E Programs (H06.08+, J06.03+)

Relation Conditions With Pointer Operands
pointer-subject
pointer-object
identifier-1
is a level-01 or level-77 data item defined in the Linkage Section or Data Division.
identifier-2
is a data item with USAGE POINTER.
NULL, NULLS
is a null address (all 1s) that causes an address fault if a pointer with that value is referenced.
NULL or NULLS can be used for pointer-subject or pointer-object, but not both.
relationship
Class Conditions
The class condition determines whether the operand is numeric, alphabetic, lowercase alphabetic,
uppercase alphabetic, or contains only characters in the set defined by a CLASS clause in the
SPECIAL-NAMES paragraph of the Environment Division.
Conditional Expressions 269