RPG Programming: Proven Platform for Transaction Processing and Modern Software Applications
Time to read- 7 min, 12 sec
RPG is a high-level, fully procedural programming language used by businesses to create commercial business applications on IBM’s leading minicomputer system, the AS400 or iSeries. Today several mission-critical business applications are written in RPG based on RPG IV because it provides an interactive programming environment to AS400 RPG Programmers. RPG was upgraded to RPG II in the 1960s, following the development of the IBM System/3. RPG5 is a free version of the ILE format from IBMi V5 RPG6 is a free version of the ILE format from IBM i V6. RPG 7 is a free and latest version of the RPG programming language and is widely used in various industries.
The Report Program Generator (or RPG) is a high-level programming language. It is one of the IBM new technologies, or you can say proprietary as400 programming module. The custom RPG was launched with various modules, and its version can be accessed only on as/400 system or IBM iSeries. However, most of its versions can only be accessed on IBM AS/400 system or OS400 (operating system) based setup.
What Does Report Program Generator (RPG) Mean?
RPG has quite a long history. As discussed above, RPG language, which people generally call it, is a programming language used for business applications and IBM iSeries and Power Systems. Initially, RPG programming was developed as a report-writing tool in the 1960s, but later it evolved as a modern RPG and into a high-level as 400 programming language for IBM products.
RPG is a high-level fully procedural programming language used by businesses to create commercial business applications on IBM’s leading minicomputer system, the AS400 iSeries. RPG has gained wide acceptance and has evolved massively since its inception. Today several ERP’s and mission critical business applications, are written in RPG based on RPG IV, because it is enabled to provide an interactive programming environment to AS400 RPG Programmers. With state-of-the-art security features and seamless integration with IoT and Watson AI; IBMi is the platform of choice for secure and data heavy business applications. RPG has a very rich legacy and it is known to be one of the finest high level programming languages. Let us share a glimpse into the journey of RPG from a report generator tool to an ILE compatible programming language.
In 1960’s, RPG was upgraded to RPG II following the development of the IBM System/3. One of the most noteworthy aspect was the fixed format programming offered by RPG II. This meant code was written in fixed format in order to standardize the software creation process and generate the desired output.
RPGIII: It was mainly developed for System38 and its following versions. RPGIII is an enhanced version over RPG II and incorporated features to support new software development structures such as iterative loops and subroutines. Further, it also allowed programmers to code in with or without the logic cycle, using indicators or IF statements. The RPG III compiler lives on to this day in AS400 and iSeries as the RPG/400 compiler.
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When IBM announced the launch of the AS/400 system, IBM changed the names of most of its software tools and compilers to identify the product with the AS/400, differentiating it from the System/38 or System/36 hardware platforms. Thus, the RPG/400 compiler package was included with the AS400 platform.
RPGIV/RPGLE: It was launched in 1994 and incorporated several features to make it competitive to meet modern software development requirements. RPGIV included many functional, performance, maintenance, and productivity benefits. Its ability to integrate multiple languages, free-format expressions and definition specifications provides many of the benefits of object-oriented languages.
Some of the noteworthy features of RPG1V are
Longer field names
Source level debugging
Date and time support
Additional data types
The ILE competency of RPG has opened several new avenues for RPG programmers.
Role of AS400 RPG Programmers
RPG Programmers are specially trained and their knowledge is used to develop AS400/iSeries software programs and applications. AS400 Service providers employ RPG programmers for designing new solutions to automate existing business processes or enhance existing software applications.
In case you are looking for skilled and experienced RPG programmers, look no further, Integrative Systems is here to help you create highly effective and maintainable RPG applications using the latest techniques.
RPG programming language AS400 is now the e-server iSeries, and the mainframe is zSeries. Overall, it can be named as iSeries.
The Future of RPG
In the future, all graphical, compiler, primarily text-based and web-based tools for the AS400 may be conveyed as a single incorporated bundle. The WebSphere development tool is an open, standard-based item that validates all the dialects accessible on AS400, utilizing the Application Development Tool Set (ADTS), ILE RPG, ILE Cobol, and ILE C/C++.
Specialties of RPG Programming Language
Before you start programming with the RPG, you should be familiar with all the specialties. These specialties set RPG apart from other programming languages. The specialties are in the field of:
- The program cycles
- Operation codes
One of the most significant advantages of RPG programming language is that it is ILE compliant. It means that the programmers have a vast number of practical, presentation, maintenance, and efficiency benefits apart from the ability to combine more than one language.
- RPG5 is an unrestricted version of ILE format from IBM i V5
- RPG6 is a free version of the ILE format from IBM i V6
- RPG 7 is a free and latest version of RPG programming language and is widely used in various industries.
Why Choose RPG Programming? Why not JAVA or PHP?
- In many IBM iSeries shops, there’s a lot of RPG programming talent, and the good thing is most of the business rules in the process today are written in RPG language.
- It takes time and money to learn any new language.
- In comparison to RPG language, Java requires more hardware (primarily when used through WebSphere).
- Many organizations, especially SMEs, do not requires additional features WebSphere/PHP.
- It’s easy to get started with AS400 programming in the RPG language. In case you come across any difficulty in modern RPG, upgrade it. And this will be the steppingstone to the future.
How to Define Null-Capable Variables in an RPGLE program?
To define null capable fields, ALWNULL (*USRCTL) must be specified on the H-Spec.
Apart from the parameters defined with OPTIONS (*NULLIND), null-capable variables can be defined in externally described files. However, there is no custom RPG support for specifying the null-capable variables.
RPG Open Access Handler
A handler in any programming language is an occurrence created for a specific task. RPG open access handler is a technique that handles the communication with the available resources and gadgets. The access is a way for RPG programmers to use the RPG I/O version to use resources and gadgets that aren’t supported by RPG.
The access offers RPG’s report I/O capabilities, permitting each person to jot down new I/O handlers to access different gadgets.
RPG Rolled Out on Various Platforms
Every RPG programmer knows that the RPG’s initial versions were developed for IBM systems like 1401, /360, /3, /32, /34, /36, /38, and AS/400. Later on, it changed into improved and carried out for Sperry Univac BC/7, the Digital VAX, Siemens BS2000, Univac device 80, Burroughs B700, B1700, and plenty of more. The cutting-edge platform advanced for the RPG compiler is Windows .Net thru the WINRPG compiler.
RPG Programming: How can Integrative systems help you?
RPG programmers at Integrative system can help you with:
- Analysis, designing, improvement, and development of pre-written IBMi software program in various languages like RPG, RPG ILE, RPG-FREE and SQL
- The programmers will help you in following specifications to create technical documentation and create pseudo-codes
- Creating new RPG applications or making the existing one stronger
- In the case of any trouble, programmers also can troubleshoot your business processing to diagnose the issue
- Additionally, they can debug any software program to find and resolve the issue
- Implement new codes and fix bugs from the existing one.
How Is RPG Programming Capable to Solve Unique Challenges
Advantages of ILE:
- RPG IV is more understandable than older column-based RPG400 and RPG3.
- It allows extra utility modularity with static binding; this means there will be fewer outside calls.
- Enhances RPG programmer’s productivity by permitting reuse of higher codes
- Enhances the use of mixed languages by allowing the binding ILE languages right into an individual software.
- Builds a base for the future through shifting close to item orientated design, modular programming, and code reuse
Enhancements in RPG Programming
- Mixed case access permitted
- The compiler isn’t case sensitive
- The compiler can translate combined case to higher case.
- Character names allowed
- Full DDS duration supported
- Columns to be had for subscripts
- Under-score allowed in names
- Blank traces allowed making it extra readable
RPGIV helps in date, time, and time-stamp data types to help you calculate durations.
Obtain portions of dates and times
- Move data from one field to another
- Compare their values
- Test for legitimate values
The supported data types are-
- D for date
- T for time
- Z for timestamp
Expressions in RPG Programming:
- More particular outcomes while using expressions
- RPGIV is less complicated in terms of understanding and maintenance, as it manages half of the adjustments & avoids utilization of transient variables
- Three forms of expressions: Arithmetical, conditional and string
Advanced Functions in RPGIV:
RPGIV offers you many superior features that make your code less complicated. It provides you with effective integrated features that let you to code more effectively.
RPG IV Program Specifications
RPG language code is written on a variety of specification forms, each having a particular function. In addition, many of the entries which make up a specification type are position dependent. Therefore, each entry must start in a specific position depending on the type of entry and the type of specification.
Mainly there are seven types of RPG IV program specifications. Each class is optional and must be entered into your source code in the order given below:
- Control provides the info about generating and running programs, such as name, date format, and sequence or file translation.
- The file gives information about all the files that your program uses.
- The definition specifies the data used by the program.
- Input tells about the fields used by the program and the input records.
- Calculation control specific input and output operations and describe data orders.
- The output tells about the field chosen by the program and output records.
- The procedure specifies the beginning and end of the sub-procedure.
- The definition tells about the local data used in the sub-procedure.
- Calculation describes the order of analyses done on global and regional data.
Why are RPG Programmers Hard to Find?
A few years ago, some techies grumbled about the lack of expert and experienced AS400 programmers. According to them, AS 400 programmers are getting retired, and the pool of talented AS400 administrators is shrinking. But the reality is different; there is no lack of RPG AS400 developers. Few IBM technologies might be old, but it is one of the most reliable application outsourcing services providing company.
Moreover, RPG AS400 codes have evolved over the years, from copyrighted to open, from a rigid structure to RPG ILE, and from RPG language to AS400 RPG “free form.” In short, IBM modified its code and operating system over the years, which conserved its domination. That transformation allowed for transitions from legacy systems to modern RPG.
This is an intelligent move from IBM iSeries since young programmers were learning the new AS400 RPG language at college.
What’s Ahead for RPG Programming?
You are the one who can make the best decision for your business but sticking to the reliability of legacy solutions alongside modernizing them. According to various industry experts, it’s a good practice to move away from AS 400 programming. Still, there is no competition for a technology that can be affordable, powerful, migratable, and energy efficient.
Launching the AS400 RPG software in the 1960s does not necessarily make it outdated. Ultimately, it provides a solid base to grow that modern RPG can’t offer in today’s era. Most industries are fighting for existence as safety and security of data are most important, and AS 400 programming is a worthy defender.
Why Choose Integrative Systems?
One stop solution for all your company’s iSeries AS400 Needs
At Integrative, once you talk to our expert and experienced RPG programmers, all the hassle of dealing with various consulting firms and third-party contractors will be out of your life forever.
Highest Quality iSeries AS400 Consultants in the Industry
Because of our more than 20 years’ experience in this field, you’ll get peace of mind by choosing us, and you will not have to worry about quality, communication and commitment.
Quick Resolution of your RPG queries
Our RPG programmers have extensive knowledge of AS400 and start producing results immediately. We work tirelessly to provide quick resolution on time and within budget.
Whether you are looking to completely outsource your iSeries AS400 or want us to complete a single project, we can help you with everything or let’s say any type of AS400 project.
For more than 20 years, we have been providing our clients with the industry’s best iSeries AS400 services at extremely affordable rates.
Lastly, we just want to conclude by saying that RPG programming language has a long history of development and it is not going anywhere. The language was initially developed as a report program, and now RPG programming language is counted as one of the finest and high-level languages, like COBOL and PL/I. Although, due to so many versions, it has created confusion, but has developed quite rapidly in comparison to other languages. Many companies that are primarily based on IBMi depend upon the RPG programming languages to enhance the capabilities and create new solutions.
RPG programming is known as one of the best languages like COBOL and PL/I in today’s scenario. Mainly used on IBM iSeries AS400 systems, the AS 400 programming language have so many versions. Although programmers get confused sometimes due to lots of versions, the language has evolved rapidly compared to other languages because of these versions. Many organizations working on IBM iSeries relies on modern RPG to enhance their existing solutions.
Get in touch with us for all your RPG programming or AS400 iSeries needs. You can drop in an email at firstname.lastname@example.org or call us at 1.800.468.7974 and we’ll get back to you within 1-2 business days.
You can also have a look at our other capabilities and contact us for your software development needs.