You know, sometimes all you've got to do is ask.
As many of you know, I started using IBM's WDSc about a year ago. All the typical reasons were the cause of my delay: It was too fat, it was too slow, it was too difficult to install, I had written my own Windows-based RPG editor that worked better (okay, so that last point is bias).
One of the first things I did when I started using WDSc was ask the development team why it didn't do some of the basic editing functions that virtually any other contemporary editor does (including the one I wrote). They responded, "Nobody ever asked for that feature." You mean features like drag-and-drop editing and auto-correct weren't asked for yet? Yikes!
So it occurred to me that perhaps the old days of going to COMMON twice a year and submitting Resolutions (later renamed to "Requirements") were effectively over. Few, if any, end-user requirements were being implemented in IBM System i productions simply because end users were no longer submitting these requirements.
Jump ahead eight months. I get a prereview of the i5/OS 6.1 (aka "IBM i 6.1") operating system enhancements to CL (yes, CL not RPG IV). I read through the enhancements and said the usual things that veteran RPG programmers say about CL enhancements, "Wow, I wish we had this 20 years ago." But then I thought, why not see what they've done for commands. Yes, CL commands or user-written command definitions have had virtually no enhancements since they change the maximum number of entries from 50 to 300, long before PowerPC was a word. Sure, they added support for IFS paths/folder names, but no enhancements from which programmers would benefit.
After reviewing the CL enhancements, I called Greg Veal, author of "CL Programming for the IBM AS/400," who continues to be not only a great resource for System i development, but he stays in touch with IBM on the latest and greatest CL enhancements as well. I complained to Greg that I was disappointed that IBM had not yet implemented the ability to consolidate some of the compiler options for command definitions. It is a pain to remember to prompt the CMD compiler every time I create this or that CL command just to enter ALLOW(*IPGM *BPGM) and, more recently, ALLOW(*IPGM *BPGM *IMOD *BMOD). My request was to make the compiler figure it out and do it anyway.
Apparently, Greg shot my request off to IBM, who responded with a question or two, which I answered and sent back to them.
Today, as I started writing this article, I signed on to the newly installed Power system running i 6.1 and was about to write an example of how to pass a qualified file name using user-written CL command definitions to RPG IV. When I entered SEU (yes, it was SEU because I like the prompter better), I prompted the "CMD" command, which is the statement that allows you to enter a text description for the command. For example, the CPYF command would have "CMD PROMPT('Copy File')" specified as the CMD command statement. To my surprise, the command no longer had a single, lonely PROMPT parameter; it had many of the compiler parameters as its own parameters. This, like RPG IV's Header spec, allows you to embed compiler parameter right inside the source code. This is a huge benefit to the next person who needs to compile the source code.
Here's an example of the CMD command statement's prompt:
Command Definition (CMD)
Type choices, press Enter.
Label . . . . . . . . . . . . . > DSPFILE
Prompt text or message ID . . . PROMPT > 'Display Database File'
Message file for prompt text: PMTFILE __________
Message file . . . . . . . . . __________
Library . . . . . . . . . . *LIBL
Message text . . . . . . . . . *STATIC
Message file . . . . . . . . . . MSGF __________
Library . . . . . . . . . . . *LIBL
Text 'description' . . . . . . . TEXT ______________________________
___________________
Maximum positional parameters . MAXPOS __________
Where allowed to run . . . . . . ALLOW __________
+ for more values __________
Mode in which valid . . . . . . MODE __________
+ for more values __________
More...
Paging down to page 2, gives us the following:
Command Definition (CMD)
Type choices, press Enter.
Allow limited users . . . . . . ALWLMTUSR __________
Threadsafe . . . . . . . . . . . THDSAFE __________
Multithreaded job action . . . . MLTTHDACN __________
Validity checking program . . . VLDCKR __________
Library . . . . . . . . . . . *LIBL
Prompt override program . . . . PMTOVRPGM __________
Library . . . . . . . . . . . *LIBL
Help identifier . . . . . . . . HLPID __________
Help panel group . . . . . . . . HLPPNLGRP __________
Library . . . . . . . . . . . *LIBL
Help search index . . . . . . . HLPSCHIDX __________
Library . . . . . . . . . . . *LIBL
Current library . . . . . . . . CURLIB __________
Product library . . . . . . . . PRDLIB __________
Authority . . . . . . . . . . . AUT __________
The big one for me is the ALLOW parameter, which I use whenever I write a CL command that can only run inside a CL program. Others I use often are PRDLIB and MAXPOS. Occasionally, I'll use the MSGF parameter as well.
A big Thank You! goes out to IBM Rochester and Guy Vig for enhancing this subtle area of user-written command development. But it doesn't end here.
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After discovering the enhancement to the CMD statement, I recalled hearing that IBM was adding this capability to CL itself. So I went into SEU and did a F4 (prompt) on a blank line. Then I selected option 1 to display a list of command by command name. First I tried "CMD*", but only the "CMD" command was listed. Then I tried "DCL*" and got lucky; the DCLPRCOPT (Declare Processing Options) keyword is the CL version of embedded compiler parameter. The prompted DCLPRCOPT command looks like this:
Declare Processing Options (DCLPRCOPT)
Type choices, press Enter.
Label . . . . . . . . . . . . .
Subroutine stack depth . . . . . SUBRSTACK __________
Log commands . . . . . . . . . . LOG __________
Allow RTVCLSRC . . . . . . . . . ALWRTVSRC __________
Text 'description' . . . . . . . TEXT ______________________________
User profile . . . . . . . . . . USRPRF __________
Authority . . . . . . . . . . . AUT __________
Sort sequence . . . . . . . . . SRTSEQ __________
Library . . . . . . . . . . . *LIBL
Language ID . . . . . . . . . . LANGID __________
Storage model . . . . . . . . . STGMDL __________
Default activation group . . . . DFTACTGRP __________
Activation group . . . . . . . . ACTGRP __________
More...
F3=Exit F4=Prompt F5=Refresh F12=Cancel F13=How to use this display
F24=More keys
Declare Processing Options (DCLPRCOPT)
Type choices, press Enter.
Bind service program: BNDSRVPGM _
Service program . . . . . . . __________
Library . . . . . . . . . . *LIBL
Activation . . . . . . . . . . *IMMED
+ for more values _
Binding directory . . . . . . . BNDDIR __________
Library . . . . . . . . . . . *LIBL
+ for more values __________
*LIBL
Bottom
F3=Exit F4=Prompt F5=Refresh F12=Cancel F13=How to use this display
F24=More keys
IBM Rochester seems committed to enhancing the operating system's scripting language (i.e., CL) after decades of neglect. I'm still not convinced that this means a whole lot to me, but I do think that adding the compiler parameters is a huge help. The more we can do to get rid of those pesky notes about how to compile this or that program, the better and more practical things will be. So, Thank You IBM!
Bob Cozzi is the host of RPG World Live [4], a live, weekly two-hour show on System i developments. It is aired each Friday from 10:00 AM to Noon, Central time on ustream.tv and on RPGWorld.com. Bob also produces RPG World, the most popular RPG IV developer conference of the year.
Links:
[1] http://systeminetwork.com/author/bob-cozzi
[2] http://www.amazon.com/dp/1583041214?tag=rw0c-20&camp=14573&creative=327641&linkCode=as1&creativeASIN=1583041214&adid=0FDDKRAMASMW6SZB3462&
[3] http://www.amazon.com/dp/1583041214?tag=rw0c-20&camp=14573&creative=327641&linkCode=as1&creativeASIN=1583041214&adid=0FDDKRAMASMW6SZB3462&
[4] http://www.rpgworld.com