Debugging original program model programs

Testing functions are designed to help you write and maintain your applications. You can use testing functions to run your programs in a special testing environment while closely observing and controlling the processing of these programs in the testing environment. You can interact with your programs using the testing functions. You can use the functions to perform the following tasks:

• Trace a program's processing sequence and show the statements processed and the values of program variables at each point in the sequence.
• Stop at any statement in a program (called a breakpoint) and receive control to perform a function such as displaying or changing a variable value or calling another user-defined program.

No special commands specifically for testing are contained in the program being tested. The same program being tested can be run normally without changes. All test commands are specified within the job the program is in, not as a permanent part of the program being tested. With the testing commands, you interact with the programs symbolically in the same terms as the high-level language (HLL) program was written in. You refer to variables by their names and statements by their numbers. (These are the numbers used in the program's source list.) In addition, the test functions are only applicable to the job they are set up in. The same program can be used at the same time in another job without being affected by the testing functions set up.