From recent questions on Internet lists, and from one-on-one discussions with RPG programmers, it seems that many are confused about the usage and operation of a number of built-in functions (BIFs). In particular the BIFs %XLATE, %REPLACE, %SCAN, and %CHECK seem to cause a lot of confusion. In this tip, I focus on %CHECK and %SCAN. I’ll look at the other misunderstood pair, XLATE and REPLACE, in a future tip.

The %SCAN BIF has been with us since V3R7, when it was introduced along with %EDITC and %EDITW, to improve string handling. %CHECK, on the other hand, is a relative

A shop with which I’m acquainted had an undesirable experience recently. A program that, to my understanding, had been working properly, ended abnormally. The error could have easily been avoided, had the programmer followed one simple rule of thumb.

Take a look at the following program fragment.

D MyData          ds                 
D  OneField                      4a  
D  TwoField                      7p 0
D  RedField                      3s 0
D  BlueField                     5u 0
D                                    
D Number          s             15p 5
                                     
 /free                               
     Number = TwoField;              

If the calculation is the first executable statement in the program, what is the new value of Number? The answer is that Number never gets

Rather than cover one topic this week, let’s look at three issues that recently crept into my in-box. I’ll explain some additional work you may need to perform to keep Help/Systems’ Robot/SCHEDULE software running fat and happy during Daylight Saving Time changes; go over my updated list of i5/OS system monitoring tools; and expand on what type of post-upgrade backups you should perform after an i5/OS software upgrade.

Another Daylight Savings Problem To Worry About

United States Daylight Savings Time (DST) begins this year on March 8, 2009.

Believe it or not, it’s only been since i5/OS V5R3 that IBM