This module covers an overview of the programming in RPGLE. The learners will be introduced to all the flavours of coding(fixed/free). The different execution environments are introduced to the learners. ILE and OPM are the approaches to programming in IBM i. This module focusses on coding the RPGLE programs in the OPM environment.
RPGLE is one of the Robust and modern Languages in the family of High-Level Languages in IBM i(AS/400). It provides many ready-made functions which makes the programmers task very easy. It is a structured programming language.
History and Evolution
- RPG II: The original RPG, introduced in the 1960s, was designed for business applications and focused on report generation.
- RPG III: Introduced with the System/38, brought significant improvements in functionality.
- RPG IV (RPGLE): Released with AS/400 in the 1990s, it introduced a more modern syntax and greater flexibility.
Key Features of RPGLE
- Free-Format: Unlike earlier versions, RPGLE supports free-format coding, making it easier to read and write.
- Built-In Functions: Includes numerous built-in functions for string manipulation, date handling, and more.
- Modular Programming: Supports modular programming with subprocedures, making code more organized and reusable.
- Integrated with SQL: Allows embedding SQL statements directly in the code for database operations.
In the Fixed-format, the entire RPGLE program is coded in different specification in a particular sequence. Each specification has a specific significance and usage. Each specification is optional and they must be entered in the order given below.
Following are the specifications focussed in this module:
- Control specifications(H) – Used to provide the compiler the information about generating and running programs, such as the program name, date format, and use of alternate collating sequence or file translation.
- File description specifications(F) – Used to declare all the files that a program uses.
- Definition specifications(D) – Used to describe the data used by the program. Used to declare the variables, arrays and data structures.
- Input specifications(I) – Used to describe the input records and fields used by the program. Mostly used if a flat file is declared in the F-specification.
- Calculation specifications(C) – Used to code the logic of the program.
- Output specifications(O) – Used to describe the output records and fields used by the program.
Development Tools
- Rational Developer for i (RDi): An Eclipse-based IDE for RPGLE development.
- SEU (Source Entry Utility): A text editor for writing RPGLE programs.
Learning Resources
- IBM Documentation: Extensive documentation and guides available on the IBM website.
- Books: “Programming in RPG IV” by Bryan Meyers is a great resource.
- Online Courses: Platforms like GoLogica and LinkedIn Learning offer courses on RPGLE programming.
- Community Forums: Engage with the RPG community on forums like Code400.comfor support and knowledge sharing.
Practical Applications
RPGLE is used extensively in business applications, especially in industries like finance, manufacturing, and distribution. It’s known for its stability, performance, and integration with IBM i systems.
Would you like to delve deeper into any specific aspect of RPGLE programming?
