Rexx Lab 1 Itt 340 Note If You Are Still A Little Sha 253691
Rexx Lab 1 Itt 340note If You Are Still A Little Shaky About Ispf
REXX_ Lab_1 ITT 340 NOTE: If you are still a little shaky about ISPF, I strongly encourage you to go through the ISPF Help tutorial in Course Materials! This lab is intended to give you some familiarity with the REXX scripting language. REXX is the easiest programming language I have encountered. It is used in the mainframe world to script a lot of repetitive tasks like creating datasets and performing backups. Knowing some REXX basics is essential to work in a mainframe environment.
You can find enough information to do this lab in the REXX tutorial in the REXX Stuff section in Course Materials. REXX is what’s called a “weakly typed” language, a language where you don’t declare the data types of the variables you use (unlike Java and C++ which are “strongly typed” languages). REXX is also interpreted, meaning it executes line by line of the source code. You can also compile REXX, but we can talk about that later. On the mainframe, you need to have this line at the top of each of your REXX scripts (and it must be the first line): / REXX [and some other comments here] / The simplicity of the syntax can be seen in the tutorial. A very simple REXX program prompts the user for his or her name, uses it in an output message: The command “pull” acts like Scanner in Java, it takes input from the keyboard and stores it in a variable.
Paper For Above instruction
The primary goal of this lab is to familiarize students with the REXX scripting language in the context of mainframe environments, particularly focusing on dataset management and scripting tasks through ISPF. REXX's simplicity, interpretive nature, and weak typing make it accessible for beginners while powerful enough for complex automations within mainframe operating systems. This report discusses the procedures, applications, and outcomes involved in completing the lab's tasks, highlighting the importance of REXX in mainframe workflows.
The tasks assigned in this lab are designed to guide students through creating multiple members within a dataset, each containing distinct REXX programs or snippets, and executing these scripts to observe their outputs. Initially, students are instructed to add five new members to the dataset YOURID.LANG.SOURCE, naming them MYREXX1 through MYREXX5. For each member, some initial text should be added before saving, and then REXX code should be inserted. Particular emphasis is placed on inserting multiple lines using the i[x] command, which adds 'x' number of lines into the member, a technique valuable for code generation or text manipulation tasks.
Retrieving and editing these members requires navigating within ISPF, primarily using arrow keys, with commands such as ENTER to prepare for saving and F3 or SAVE to retain changes. The scripts are designed to perform various functions, including outputting hardcoded text, performing arithmetic operations with hardcoded and user-inputted values, prompting for user input via the pull function, and implementing basic control flow with IF statements.
Executing the REXX scripts involves using the TSO EX command with the fully qualified dataset and member names, enclosed in single quotes. Copy-pasting commands into the mainframe command line for execution reflects typical workflow. The lab also teaches deletion of specific lines or blocks of text within members, enhancing editing proficiency within ISPF.
Upon completing these programming tasks, students are required to upload various artifacts: screenshots of each source code, outputs of script execution, a screenshot of the dataset members, and a written reflection of at least 100 words documenting their experience. This comprehensive approach ensures understanding of both the syntax and practical applications of REXX scripting in mainframe environments.
Overall, mastery of REXX scripting is crucial for automating repetitive tasks, managing datasets, and customizing workflows in mainframe operations. The simplicity of REXX's syntax combined with its powerful capabilities makes it an invaluable tool in legacy systems, ensuring efficiency and reliability in enterprise computing environments.