IBM i Fundamentals

An ordered path through the foundational IBM i concepts every beginner and working developer benefits from knowing.

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Showing 17 of 288 lessons

10Job Logs and Spool Files BasicsLog in to accessWhat job logs and spool files are, how they help with troubleshooting, and how they differ from physical and logical files.
145Why Debugging Matters on IBM iLog in to accessWhy debugging is a normal, routine part of IBM i development, not a sign that something has gone wrong.
146STRDBG Basics for RPGLELog in to accessWhat STRDBG does, what a program needs before it can be debugged this way, and what happens once the debugger starts.
147Setting and Using BreakpointsLog in to accessSetting a breakpoint at a specific line, running a program until it stops there, and stepping through its logic.
148Watching Variables During DebugLog in to accessDisplaying a variable's current value while paused in a debug session to confirm or rule out where a calculation goes wrong.
149Understanding Job LogsLog in to accessWhat a job log actually contains, using DSPJOBLOG to view one, and why it is one of the most important IBM i troubleshooting tools.
150Reading IBM i Message IDsLog in to accessThe structure of an IBM i message ID, such as CPF9897 or RNQ1218, and why that structure matters for understanding a message.
151Compile Errors vs Runtime ErrorsLog in to accessDistinguishing a compile error, caught before a program runs, from a runtime error, which only surfaces while it executes.
152Common IBM i Debugging MistakesLog in to accessThe most common beginner mistakes when debugging on IBM i, and a simple set of best practices to avoid them.
153DSPJOB and Job Information BasicsLog in to accessWhat DSPJOB shows, and how to use it to inspect a job's log, call stack, library list, and basic attributes.
154WRKACTJOB Basics for DevelopersLog in to accessUsing WRKACTJOB to find active jobs on the system and read their basic status.
155Finding Program Failures from Error MessagesLog in to accessMoving from an error message in a job log to the specific program and statement that actually failed.
156Understanding Call Stack BasicsLog in to accessWhat a call stack is, and how to use it to see which programs and procedures are currently active in a job.
157Debugging Batch Jobs at a Beginner LevelLog in to accessThe basic practical difference between debugging an interactive job and a batch job, and a simple beginner-level approach.
158Using Job Logs for SQLRPGLE and File I/O IssuesLog in to accessConnecting job log messages to specific SQLRPGLE and native file I/O problems covered earlier in this path.
159Basic Troubleshooting Flow for IBM i DevelopersLog in to accessA simple, ordered troubleshooting flow that connects every debugging tool covered across this lesson group.
160Debugging Checklist for BeginnersLog in to accessA condensed, practical checklist to run through during an actual debugging session, drawing on both Debugging Batches.