Rational Developer for System z
PL/I for Windows, Version 8.0, Programming Guide

Specifying run-time options

Each time your application executes, a set of run-time options is established. These options determine some of the properties of the application's execution, such as allocation of storage and production of reports. IBM supplies defaults for each of the run-time options; however, you can change them as needed prior to running your application.

Rational Developer for System z
PL/I for Windows, Version 8.0, Programming Guide