Identifying a program as recursive
Code the RECURSIVE attribute on the PROGRAM-ID
clause to specify that a program can be recursively reentered while
a previous invocation is still active.
About this task
You can code
RECURSIVE only on the outermost program of a compilation unit.
Neither nested subprograms nor programs that contain nested subprograms can be recursive. You must code RECURSIVE for programs that you compile with the
THREAD option.Note: A
PERFORM statement must not
cause itself to be executed. This constitutes a recursive PERFORM, which can cause
unpredictable results. Therefore, you must not specify recursive PERFORM
statements. See Basic
PERFORM statement for details.Refer to the Example: storage sections, which shows that a recursive program uses both WORKING-STORAGE
and LOCAL-STORAGE.
Note that a recursive program will have only 1 copy of
WORKING-STORAGE, but a new copy of LOCAL-STORAGE for each
CALL.