The book includes over 60 compiled rpg iv listings documented with a line by line explanation of the instructions and or annotated comments. Which is the best site to learn as400, rpg, and rpgle. How to use the ile debugger to display the value of a. Rpg3 rpg400 rpgle in all its glorious free format styley. Using the proven and easytouse progen plus design tool you can produce both ile rpg or rpg400 programs 8 to 20 times faster. Eval opcode is used to evaluate any kind of expression in rpgple. The style here could be described as a blend of rpgii, rpgiii, and rpg400. Pathfinder for the iseries as400, power systems, system. Rpgs move fields logic, and its cousin evalcorr ibm. You may still maintain and create new greenscreen rpg applications, but you also are probably moving rpg programs into different environments, including those that deal with the world wide web. The may 10 edition of club tech programming tips included a random number generator for rpg iv, but unfortunately, that wont work for me, as im using rpg400.
We are committed to working with your staff to provide maximum benefit by fully utilizing pathfinder. I was trying to debug an ibmi web interface program ibm rpgfreeformat language that was blowing. By using the code examples, you agree to the terms of the code license and disclaimer information. Pathfinder for the iseries as400, power systems, system i preevaluation profile. Slowly but surely, todays rpg programming is moving out of the familiar, comfortable environment that most of us have known. Mckesson software group embraces rpg iv, ile, webfacing, and java to transform its own while also helping to transform its customers into modern, efficient, and qualitydriven healthcare. There is a more recent version of this tutorial that uses a more modern form of rpg iv, with more types of freeform statements. He also worked on the creation of the cobol400 compilers for the original as400s back in 1988, and was one of the key developers behind rpg iv and the code400 development tool. Rpg short form expressions the free format rpg is full of shortcuts which save you typing time. Welcome to it jungle is another good repository of ibm i materials.
Convert rpg iii and rpg400 source code to modernized rpg iv syntax. I have learned how to change a set of records in one fell swoop with the update command. Here is a description of rounding from chapter 9, calculation specifications, of the rpg400 reference. Free as400, iseries, and system i iseries downloads. Additionally all program described fields as above are converted to d. To display the value of any variable in hexadecimal format, simply specify. Bob cozzi, a wellknown rpg expert, posed a question about how long it took to actually code the implementation of freeform to hans boldt, who evidently was on the team at ibm that developed the original implementation. For introductory and advanced courses on rpg iv in computer science and computer information system departments. The integrated file system is a part of os400 that supports stream inputoutput and storage management similar to personal computer and unix operating systems, while providing an integrating structure over all information stored in your server. The first reason is if you have to deploy your programs to an os400 release lower than v5r1 since freeform rpg is only supported in v5r1 and higher. All software necessary to run this computer is included and integrated.
At least one space must separate the pieces of the statement. The author has included over 500 figures and he addresses other important as400 software with separate appendices for seu, pdm, dfu, sda and interactive. The eval operation code evaluates an assignment statement of the form result expression or result op expression. Maybe this is a result of the way you pasted it into your message, but rpg is column specific for most elements. The as400 application system400 was first introduced by ibm on june 21st, 1988 and later renamed to as eserver iseries in 2000, then in 2006, it was renamed as system i. For instance, to enter an eval statement using a fixedformat c specification within. Freeformat rpg uses many of the same operation codes. I have an old rpg progam that i had to make some changes to, so while i was at it, i updated it to rpgle. June 23, 2004 hey, ted thanks for the many sql tips you and others provide in four hundred guru. How to handle nulls is becoming one of the more popular questions i am asked. One could add this number to that, or compare this variable to that. Computek consulting iseries as400 consulting and edi.
The eval operation code evaluates an assignment statement of the form result expression or result. Ok, all this works and the dataflow is actually pretty nice. Rpg400 technical job interview questions of various companies and by job positions. Until recently, it had been difficult to convert between numeric and character values in languages other than rpg. 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. Actually, i think the biggest problem with the eval statement is not the eval statement itself and its use of overflows, but the method the as400 stores numbers. C move 400 string 4 c rpg cat string temp 7 c c the following example is the same as the previous example except c that temp is defined as a 10 byte field. Dont know why i thought that, i guess i just jumped to a logical conclusion. In rpg, we simply used the move opcode and numerictocharacter or charactertonumeric conversion was magically done for us. Mckesson software group embraces rpg iv, ile, webfacing. The ilerpg development environment lets you take advantage of features of rpg that are only available in ile. Therefore, result cannot be a literal or constant but must be a field name, array name, array element, data structure, data structure subfield, or a string using the %subst builtin function.
But the real fun begins when you combine the features. Rpg is an ibm proprietary programming language and its later versions are available only on ibm i or os400based systems. Eval action, which lets you write freeformat calculations. Flybynight software os400, i5os technical specialists. Theres still times when i write software in rpg for a customer and one of their staff rpg programmers says, wow, i didnt know you could do that.
He learned rpg from the ground up in that environment. My first guess is that there is some difference in your definitions causing the problem, but without the code, it is impossible to say. Paris cut his teeth on the system38 way back when, and in 1987 he joined ibms toronto software lab to work on the cobol compilers for the system38 and system36. In version 3 release 7, as400 programming languages and application development tools offers a number of software solutions to help customers expand into the world of clientserver application development. Your partner in as400 and iseries education free your rpg jon paris jon.
I worked for a software development house that wanted the ibm look and feel on all of its screens. One of the cool features of rpg is the move fields logic where data is moved from input buffers to program fields and from program fields to. The freeform coding style has been available for rpg iv since ibm released. Nach weiterentwicklungen rpg ii, rpg iii, rpg 400 konnen neuere projekte inzwischen mit dem besseren rpg iv ile rpg geschrieben werden. Sql statements in rpg 400 programs this example program is written in the rpg programming language. Could you provide your code so that we can take a look. I tried to get the same results in my new program using an evalh instead of two operations of mult and divh here are the variable. In 2008 system i got unified with system p to become power system. The thinking was that users familiar with the as400 would be comfortable using the interactive screens in our software and would require less training. Rpg debug display large field content nick litten is ibm. Using the eval statement in rpg iv mc press online forums. Whats the difference between eval and move in rpgle stack. This book is dedicated rpg iv programming language and the as400 environment. You should be using the lpex editor to key in the source.
A programming guide to learn as400 toggle navigation as400 tutorial. Designed for those new to rpg iv the primary computer language now used on the as400 this text begins at an introductory level and introduces new and more difficult topics in a building block fashion. Codds relational database model, which is based on codds 12 rules, in the operating system and hardware. The expression is evaluated and the result placed in result.
Find answers to rpgle arrays from the expert community at experts exchange. In rpg iv, the intermediate results computed by the eval operation assume that digits to the left of the decimal point are more important than digits to the right and since the largest result allowed is 30 positions, truncation can occur during the computation. The rather slow acceptance of freeform rpg since its inception has been intriguing to me. My first cgi program a simple cgi program for the rest of us with bob cozzi support provided by rpg xtools enjoy programming again. Nick litten dot com is a mixture of blog posts that can be sometimes serious, frequently playful and probably downright pointless all in the space of a day. Actually, i think the biggest problem with the eval statement is not the eval statement itself and its use of overflows, but the method the as 400 stores numbers. Handling null in rpg i am finding that i am encountering variables containing null more often as i interface data to the ibm i that originated from other software and databases. Understanding evalcorr and actually using it code400. Rpg programming on the ibm i as400 and iseries subject. Halfadjusting is done by adding 5 5 if the field is negative one position to the right of the last specified decimal position in the result field. The new packaging options make it easy for customers to install these programs at. The toolbox allows you to modernize your rpg programs, develop new applications faster. For that reason, a recent discussion on the rpgiv forum has been interesting.
We believe there is only two reasons why you may not want to code in the freeform style. That way, the character format appears just as it would have, had it been output using rpg iv output specification forms and an edit code or edit word. This tells the eval statement to show me the greqdata field in. Rpg debug display large field content nick litten is ibmi, as400. Converting numeric to character and character to numeric. Even though rpg programmers tend to be creatures of habit, ill bet you dollars to donuts they didnt even realize the for operation code was avaiable. There are a reduced number of eval dspf1 f1 statements and you can format data to your desired sizes etc just with the evalcorr statement alone. In rpg iv, ibm added two operation codes that would convert numeric values into character values and allow you to mask or edit the resulting values. Maybe you can explain something i have yet to figure out. Rpg is a highlevel programming language hll for business applications. The expression may yield any of the rpg data types. Almost all pc programming languages with the exception of clipper and dbase and a few others of those types store numbers in byte format. How to sort an array in descending in rpg answer surya siram while declaring the array in the rpgle program, use the key word descend and then use the bif sorta sort array to sort the array in descending order. There is a big difference between these operation codes.