Expressions and limited freeform calculations have been part of our rpg iv coding lives since the. Subprocedures which return a value are used very much like rpg iv built in functions, as shown in the examples on this chart. Be sure you have the correct versions for your machine before you start. Rpg toolbox will modernize your rpg source code with the most uptodate free form syntax available for your ibm i release. Subprocedures which return a value are used very much like rpg iv builtin functions, as shown in the examples on this chart. Every rpg program executes programs within a hypothetical loop.
The exsr operation can appear anywhere in the calculation specifications. Youve just discovered you have a minimal amount to learn before you can start using rpg iv. Subprocedures are the rpg iv implementation of ile procedures. Rpg iv offered a greater variety of expressions within its extended factor2 calculation specification and, later in life, its freeformat calculation specifications and procedure syntax. The effort and complexity converting from opm to ile can vary widely depending on how extensively you want to exploit iles features. Rpg iv programming fundamentals workshop for ibm i. With just the basics, it is as easyif not easierto program in rpg iv as it is in rpg iii.
This edition applies to the licensed program ibm ile rpg400 program 5763rg1, version 3 release 0 modification 5, and to all subsequent releases and modifications until otherwise indicated in. Just because rpgiv has been around for ten years doesnt mean you have to use it. Linomas rpg toolbox page 6 introduction both the iseries and as400 platforms will be referred to as iseries throughout this document linomas rpg toolbox will greatly improve the productivity of developers who write and maintain software on the iseries. Say goodbye to old rpg subroutines, and get to know ile rpgs powerful sub procedures. The flexibility of the rpg toolbox allows you to convert entire source members or just blocks of source code within a member. International technical support organization who knew you could do that with rpg iv. I was at a presentation given by partner400s susan gartner and jon paris where, amongst many things, they discussed replacing subroutines in your rpg code with subprocedures.
The conversions can be performed from ibms rdi development environment, pdm or from seu. Most highlevel languagessuch as c, cobol, visual basic, and javahave some sort of subroutine feature. Rpg iv is the only version of rpg supported by ibm in its long line of successors to the as400 system iseries, system i, etc. At least one space must separate the pieces of the statement.
By focusing on realworld problems, downtoearth solutions, and the. Subroutine is coded between begsr begin subroutine and endsr end. His book the modern rpg language has been the most widely. In this chapter, we look at the numerous operations available for controlling flow in free format through conditional and selection. In the previous topic, we added a do loop to read all records in the file, an if statement to test the state for tn and a subroutine. If factor1 entry is pssr then this subroutine will handle all program exceptionserrors. Most of my time is spent teaching experienced rpg developers about new or more advanced features of the language. This edition applies to the licensed program ibm ile rpg 400 program 5763rg1, version 3 release 0 modification 5, and to all subsequent releases and modifications until otherwise indicated in new editions. Rpg iv programming fundamentals workshop for ibm i ref. Ibm rpg iv programming fundamentals workshop for ibm i. The final requirement for a line of freeformat rpg iv source is a termin ating semicolon.
In the example, dayofweek is the name of an rpg iv subprocedure. This tutorial strives to teach network programming using sockets to as400 or. This course is a comprehensive exposure to the basic features and functions of rpg iv for version 7. Begsr opcode represents beginning of a subroutine placed in factor1. Rpg iv subprocedures use prototypes, which are a way of defining the interface to a called program or procedure. To convert an rpg iii program to an rpg iv program, you merely run the source through a conversion tool and recompile the program. Accessing the db2 database using rpg iv structured programming and subroutines structured programming and.
Introduction to rpg400 programming workshop rg15 5 days 40% lecture, 60% workshop this class provides an introduction to rpg400 programming on the ibm system i as400. The effort and complexity converting from opm to ile can vary widely depending on how extensively you want to. Rpg iv introduction rpg iv introduction rpg iv introduction. Modern rpg for the modern programmer december 2016 sg24540201. When rpg was first developed, the major stronghold that it had was known as the program cycle.
For a description of the job date, see thework management manual. A subroutine is a block of code inside a program, with an identifiable beginning and end. Ocean technical conference catch the wave in this presentation we have attempted to gather together some of the information that we have collected while using and teaching rpg iv subprocedures and prototyping. The essential guide to freeformat rpg factor 1, if there is one, follows the operation code. Rpg iv also known as ile rpg is the most current version of rpg and it is a tool that provides a highly enabling programming environment for as400 rpg programmers. In this session, we will concentrate on writing and using rpg iv subprocedures, but you will find that many of the same prototypewriting skills can be applied to access system apis and c functions. This elearning computer training series includes all of the online training tutorials listed below and is provided in an interactive elearning format. This is not a complete listing of all subroutines contained in the templates but is provided as an example of naming standards. I began learning rpg in 1973 at the same time i began learning cobol. When you add an item to this list, include a link to the free pdf.
After completing the courses in this series, the users will be able to write rpg iv programs using structured design and modular programming concepts. The original style of programs is now called opm opm original program model. Systems reference library ibm 1 subroutine library. A specific subroutine that is to be run at program initialization time can be defined by specifying inzsr in factor 1 of the subroutines begsr operation. Bob cozzi is a programmerconsultant, writerauthor, and software developer of the rpg xtools, a popular addon subprocedure library for rpg iv. Rpg iii adding a loop, if and subroutine to the rpg iv program. Subprocedures, not subroutines, should be your first choice when programming. And the same is true for all free commands and parms. If you thought that rpgiv had changed over the years well you aint seen nothin yet most of us have been making extensive use of evals since they were first introduced with rpg iv in v3r1. Say goodbye to old rpg subroutines, and get to know ile rpgs powerful subprocedures. No previous knowledge of rpg is required or assumed. You can code free, free, free, free, whatever you want and the system could care less. Rpg programming language ibm rpg for business applications.
How to get the most from templates templates can save a company hundreds of programming hours over the span of a single project. The subroutine name must be a unique symbolic name and must appear as the subroutinename operand of a begsr operation. Freeformat rpg iv offers experienced rpg programmers a new style for controlling program flow. But rpg iv subprocedures are more like the features of those other languages than subroutines. If you want to, go ahead and include your thoughts on the rpg or rpg item if you have played or used it. The new rpg compiler that has ile functions is based on the 4 th specification of the rpg language, aptly named rpg iv. This course covers both fixed format and free format, with the most modern language enhancements. Rpg, cobol and cl join the party in v3r1 may 1994 rpg s syntax is changed at the same time.
Only one subroutine can be defined as an initialization subroutine. With rpg iv each source is compiled into a module module, and a number of modules may be combined into a single program. The exsr operation causes the rpg iv subroutine named in the subroutinename operand to be processed. There is a more recent version of this tutorial that uses a more modern form of rpg. You can use this section to link to and learn about new rpg iv functions. Now that you have a good understanding of the language differences between rpg iii and rpg iv, as well as the conceptual differences between opm and ile, its time to cover the specifics of ile.
Subroutine is one of the major constructs rpg iv supports to deal with top down design and modular development. Rpg iii language uses the original program model opm runtime environment, whereas the rpg iv. Subprocedures beyond the basics techniques to leverage subprocedures jon paris jon. With each release of the operating system, more features have been added. I had the good fortune of becoming employed by the college i was attending on a workstudy program, so the same people who were teaching the courses were available to me virtually all day, everyday. Java for s390 and as400 cobol programmers,1583470115 zit also contains information from the related student workbook. Introducing freeformat rpg iv 29 today, and declaring them in definition specifications makes program maintenance easier and more productive.
Program flow using free format in nearly every program you write, you need to control the flow of instructions. Rpg iv also introduced data specifications, builtin functions bifs, mixed case source, freeform expressions, larger variable names, and other features that todays rpg programmer takes for granted. Refer to the ile rpg for as400 reference, sc092508, manual for more information. Having spent the last few weeks using subprocedures in place of subroutines in any new programs i have written, i have been won over to the subprocedure side of the. The thing thats interesting to me is that he knows enough about procedures to turn them into subroutines. Just because rpgiv has been around for ten years doesnt mean you. It is the first of two courses that should be attended in sequence. The toolbox allows you to modernize your rpg programs, write applications. It is assumed that the reader of this tutorial is already familiar with the rpg iv. Rpg iii language uses the original program model opm runtime environment, whereas the rpg iv language has. If youve taught with previous editions of programming in rpg iv, youll appreciate how the new flow of the book, along with all new instructor materials, makes it easy to build a solid, modern rpg iv foundation for your students. Introduction to ile rpg iv programming course summary description this class provides an introduction to rpg iv programming on the ibm i iseries and as400.
Rpg, cobol and cl join the party in v3r1 may 1994 rpgs syntax is changed at the same time. The final requirement for a line of freeformat rpg iv source is a terminating semicolon. External subroutines calling assembler from rpg although the extensions to rpg syntax that came with rpg ii and rpg iii and undoubtedly rpg iv as well remove any barriers that prevent rpg programs from completing any task that can be achieved with any other programming language, the original rpg does have some shortcomings. The initialization subroutine allows you to process calculation specifications before 1p output. I was at a presentation given by partner400s susan gartner and jon paris where, amongst many things, they discussed replacing subroutines in your rpg code with subprocedures having spent the last few weeks using subprocedures in place of subroutines in any new programs i have written, i have been won over to the subprocedure side of the argument. If you thought that rpgiv had changed over the years well you aint seen nothin yet most of us have been making extensive use.
You enter a comment by keying two slashes followed by the text of the comment. Freeformat rpg uses many of the same operation codes. Rpgiv template documentation prodata computer services. Rpg iv tutorial pdf this tutorial strives to teach network programming using sockets to as400 or. Refer to figure 1 to see a detailed explanation of the rpg iv initialization subroutine. Ibm rpg tutorial pdf download free for beginners and experienced. But occasionally, i am asked to either teach rpg newbies or at least recommend a way to learn rpg to those who dont know the language at all. Its also important to mention that, like rpg, free is case independent. Course rpg iv programming fundamentals workshop for ibm i as06g teaches the basics of the ibm i rpg iv programming language. Im an rpg developer who is also a professional educator on rpg iv and related topics.
1231 684 974 909 1589 276 1487 539 1348 264 1076 202 972 412 274 1578 1332 764 804 467 591 826 833 1529 901 378 412 1488 1285 541 760 439 1353 11 193 679