Learn Rpg - 10 Code Examples & CST Typing Practice Test
RPG (Report Program Generator) is a high-level programming language primarily used for business applications, especially on IBM midrange systems like AS/400 and IBM i, for generating reports and handling data processing tasks.
Learn RPG with Real Code Examples
Updated Nov 20, 2025
Explain
RPG was designed for business data processing and report generation.
It emphasizes record-level file operations, calculations, and output formatting.
Still used in legacy enterprise systems, particularly in finance, manufacturing, and logistics.
Core Features
File I/O operations with input/output files
Calculations and data manipulation
Report formatting (line and column-based)
Subprocedures and modularization
Integrated with DB2 on IBM i systems
Basic Concepts Overview
Fixed-format vs free-format RPG IV
Files (input/output) and record structures
Calculation specifications (C-specs)
Report formatting (R-specs)
Subprocedures and modular code
Project Structure
src/ - RPG source files
lib/ - reusable subprocedures
reports/ - generated output files
tests/ - sample input/output files
docs/ - business rules and program documentation
Building Workflow
Write source code in RPG (fixed or free format)
Compile using IBM i compiler
Run programs on IBM i or emulator
Test file I/O and calculations
Generate business reports or batch outputs
Difficulty Use Cases
Beginner: simple calculations and report generation
Intermediate: batch data processing and DB2 integration
Advanced: interactive IBM i applications
Expert: large enterprise system maintenance
Legacy migration or integration projects
Comparisons
More specialized than COBOL for report generation
Less versatile than modern languages
Tightly coupled with IBM i ecosystem
Stable and mature for enterprise applications
Legacy syntax differs from modern procedural languages
Versioning Timeline
1959 - RPG created by IBM for IBM 1401
1960s - RPG II for IBM System/3
1978 - RPG III for IBM System/38
1994 - RPG IV introduced with free-format syntax
2000s+ - Ongoing updates for IBM i compatibility
Glossary
F-spec: file definition
D-spec: data definition
C-spec: calculation spec
RPG IV: modern free-format RPG
Subprocedure: modular reusable code
Frequently Asked Questions about Rpg
What is Rpg?
RPG (Report Program Generator) is a high-level programming language primarily used for business applications, especially on IBM midrange systems like AS/400 and IBM i, for generating reports and handling data processing tasks.
What are the primary use cases for Rpg?
Generating business reports. Batch data processing. Financial calculations. Inventory and logistics management. Legacy enterprise application maintenance
What are the strengths of Rpg?
Highly optimized for business data processing. Legacy systems are stable and reliable. Deep integration with IBM i/AS400. Efficient for batch report generation. Strong backward compatibility
What are the limitations of Rpg?
Steep learning curve for modern programmers. Legacy syntax can be cumbersome (fixed format). Limited use outside IBM i ecosystem. Modern web and GUI support is limited. Difficult to integrate with non-IBM systems
How can I practice Rpg typing speed?
CodeSpeedTest offers 10+ real Rpg code examples for typing practice. You can measure your WPM, track accuracy, and improve your coding speed with guided exercises.