|Duration: 3 or 4 days|
|Participants: Application programmers and developers, technical support personnel, and end users.|
Upon successful completion of this course you will be able to:
- Code, test, and execute powerful REXX execs that accomplish a variety of utility and programming tasks in an MVS/ESA environment.
- Code REXX programs that customize JCL and submit MVS background jobs.
- Use built-in REXX functions, including those specific to the TSO platform, and write your own internal and external functions and subroutines.
- Perform file I/O using the EXECIO statement.
- Execute batch REXX execs using JCL.
- Invoke TSO foreground applications.
- This course emphasizes REXX features that are particularly useful in an MVS and TSO environment.
- We present this class in 3 days for experienced programmers. For a class of students with no programming experience, we present a 4 day course omitting complex program logic and covering other programming-related topics in greater depth.
- We discourage including non-programmers and programmers in the same class.
- Generally, this course is followed by ISPF Dialog Manager, which provides full-screen (panel) IO, variable, library, table support, etc.
- An additional day can be added to this course teaching “structured programming using REXX”. It is added at the beginning of the course, so that all subsequent workshops reinforce the structured programming concepts.
|Prerequisites: Experience using TSO/ISPF is required. An understanding of programming concepts is strongly recommended.|
|Format: Lecture and discussion with hands-on exercises.|
- Creating and Running REXX Execs
Writing a simple exec
Running a REXX exec in the TSO/MVS environment
Running a REXX exec
SYSPROC vs SYSEXEC
REXX execs and CLISTs
TSO commands in REXX execs
- The Basics
Variables, functions, and subroutines
Buffers and stacks
- REXX Instructions
Passing arguments to a REXX exec
Deciphering error messages
- Built-in Functions
- Trapping Screen Output
- User-Written Subroutines and Functions
Functions vs subroutines
Purpose and use
Internal vs external
- File I/O and Stacks
Data stacks and queues
- Interrupt and Error Handling
Event trapping examples
- Tracing and Debugging REXX Execs
- Running REXX Execs in Batch
- Invoking Dialog Management Services
Displaying simple ISPF panels