Using tables (arrays) and pointers

In COBOL, arrays are called tables. A table is a set of logically consecutive data items that you define in the DATA DIVISION by using the OCCURS clause.

About this task

Pointers are data items that contain virtual storage addresses. You define them either explicitly with the USAGE IS POINTER clause in the DATA DIVISION or implicitly as ADDRESS OF special registers.

You can perform the following operations with pointer data items:

  • Pass them between programs by using the CALL . . . BY REFERENCE statement.
  • Move them to other pointers by using the SET statement.
  • Compare them to other pointers for equality by using a relation condition.
  • Initialize them to contain an invalid address by using VALUE IS NULL.

Use pointer data items to:

  • Accomplish limited base addressing, particularly if you want to pass and receive addresses of a record area that is defined with OCCURS DEPENDING ON and is therefore variably located.
  • Handle a chained list.