REXX (REstructured eXtended eXecutor language)

This course introduces you to REXX, describing why it is still popular today and the myriad of resources that are available to help build your skills and knowledge. It also looks at the main features of REXX and how coding in this language can benefit various job roles within the organization. Before diving into the actual REXX code, an overview of REXX programming editors is provided to assist you in identifying appropriate work tools for use with this programming language.

In this course you will discover that REXX has simple syntax and coding requirements compared to many other programming languages. You will look at the general structure of a REXX program concentrating on the types of data that can be coded. This is then wrapped around best practices, using your organization's standards and general programming rules. Finally, you will see where and how REXX program code is stored, and the different ways it can be invoked.

In this course you will begin by seeing how simple arithmetic calculations are performed using REXX, and then progress to more powerful complex calculations. You will see how a simple REXX conversational program is built, and how data passed to a REXX program can be parsed to create variables. The value and use of compound variables is also examined.

In this course you will see how functions and routines can be used to perform complex tasks quickly. You will then branch off to look at some of the more straightforward built-in functions provided by REXX. Scenarios are presented to provide you with ideas on how arithmetic and comparison built-in functions can be used.

This course looks at the built-in REXX functions that can be used format, and manipulate strings of data, as well as date and time formats. Details on converting data to and from Hexadecimal, Decimal, Binary and Character formats is also discussed. Scenarios are presented to provide you with ideas on how these built-in functions can be used.

In this course you will see how the normal sequential flow of a REXX program can be altered so that code is skipped, or repeated. Instructions used to evaluate and act on a value if it is true, are discussed, while details on methods used to loop instructions are explained in depth.

When creating any program, you need to cater for when the inevitable errors occur. In this course you will look at handling errors from two perspectives. Firstly, you will see the type of code required to branch to an error routine that will perform actions that will - help with diagnosing the problem, clean up certain activity that has occurred, and end the program. Performing diagnostics on errors that have occurred to determine the problem is also covered in depth, highlighting utilities and code used to assist with this task.

This course introduces REXX programming tailored specifically for the TSO environment. It starts by exploring two key methods for reading and writing data from z/OS data sets: EXECIO and Stream I/O. The course also covers a variety of TSO REXX functions used to retrieve information from, and interact with, the z/OS system.

This course examines the versatility and power of REXX across various mainframe environments and provides real-life use cases along the way. In particular, it explores REXX's role in streamlining tasks, automating operations, and extending functionality within z/OS, z/VM, and z/OS UNIX systems.