A UEPT will improve the performance of external program calls to user programs.

Written by Junlei Li

This article is a follow-up to my System Entry Point Table (SEPT) article. One of our readers, Mark Waterbury, suggested that I write it. In my SEPT article, I discussed the performance gains in API invocations brought by the SEPT object. Actually, to improve the performance of external program calls to user programs, you can also implement your own "SEPT," or, in other words, your User Entry Point Table (UEPT) objects for performance-critical applications following the same rationale of SEPT.

Let's explore the nuts and bolts of using embedded SQL: file type, syntax, and compiling.

Written by Tom Snyder

In a previous article, "Why Use Embedded SQL Within RPG?," I talked about why you would use embedded SQL in RPG. In this article, I will talk about how you could use embedded SQL within RPG. We'll start with an existing RPG program that is written with CHAIN and READ, and then we'll convert it to use embedded SQL.

When you try to use new techniques and technologies, do you get resistance from your own staff?

Written by Tom Snyder

Are you an RPG programmer who is dealing with resistance to updating your RPG skills from people in your staff or even management within your staff? Well, you're not alone.

I felt compelled to write this article because I have received several emails from people who are interested in updating their RPG skills, but the environment that they work in discourages skill advancement. Recently, I received a message from someone who is literally on the other side of the planet and is experiencing this kind of oppression in his shop and other shops that he's worked in.

Message descriptions are one of the unsung heroes of IBM i application development, and this article shows you how to use RDPi to manage them with ease.

Written by Joe Pluta

The message description is unique to the IBM i. The concept is simple: a seven-character key provides a link to a fully featured message, which supports both a short version suitable for presentation on a user display and a long message with enough information to provide full diagnostic and help capabilities. Such a basic idea, yet message descriptions provide a wide range of capabilities. For example, messages are contained in a message file,m and internationalization is as simple as supplying a different message file for the locale. The i had i18n before i18n was cool!

If you were a program, could you answer this question?

Written by Junlei Li

In software programming, sometimes a program, a procedure, or a process or thread needs to answer the question: "Who am I?" For example, in an error-logging framework, after getting the answer to this question, the error-logging framework might write a log entry like the following: "Failed to allocate heap storage in SOMELIB/SOMEPGM, procedure FOO of module BAR. From job QZDASOINITQUSER      123456, thread 00000030." To answer the "Who am I?" question, programmers could hard-code names of programs or procedures everywhere log entries need to be written, but doing that is obviously error-prone and will make code hard to maintain. A utility that can answer this question on behalf of any program or procedure will significantly reduce the efforts in maintaining code that writes log entries.

Implement the mutex primitive via MI instructions CHKLKVAL and CLRLKVAL.

Written by Junlei Li

Efforts of numerous computer scientists have been devoted to solving performance problems in different performance-critical circumstances. One of these performance problems is the expense in thread synchronization. Thread synchronization is the application of particular mechanisms to ensure that two concurrently executing threads do not execute specific portions of a program at the same time. By using MUTual EXclusion (mutex), access to shared resources from multiple threads can be serialized, and mutually exclusive program logic can be guaranteed to run in a single thread at any time. Thread synchronization is not limited to threads in the same process; it also applies to synchronization between different processes, or in other words, threads in different processes.

Writing new records is a standard task in any system, and this article makes one of the steps of that process a whole lot easier.

Written by Joe Pluta

One of the most critical functions of any business application is writing data to the database, which not coincidentally is one of the things that RPG does best. The whole concept of an externally described file is incredibly powerful: the ability to store data in individual fields and leave the aggregation to the compiler makes data generation a quick and simple task. However, even good techniques can still get better, and in this article, I'll show how a couple of keywords can be combined in a way that can shave precious time off of your development.

Create a PDF "Hello World" program with RPG.

Written by Tom Snyder

Editor's note: This article is excerpted from the MC Press book Advanced Integrated RPG.

I hope you enjoyed my Video Tour presented on July 21 in which I discussed the possibilities of using Java with RPG to send email and to create Excel spreadsheets and PDFs. This article contains condensed excerpts from my book that will show you how to install the iText open-source project, which can be used to create PDFs right from within RPG.