Re: Service Programs 101 -- RPG400-L

Hi Rob,

You could combine HSPEC1 and HSPEC2 as follows

H Datfmt(*USA)
H Copyright('(C) Copyright Group Dekko Services, LLC')
H ExprOpts(*RESDECPOS)
H* EXTBININT will change (B)inary to (I)nteger.
H EXTBININT(*YES)

   /If Defined *CRTBNDRPG
   /DEFINE HSpec
H Bnddir('ROUTINES/SRVPGM':'QC2LE')
H ActGrp(*CALLER)
H DftActGrp(*NO)
 /UNDEFINE HSpec
 /EndIf

Paul Tuohy



----- Original Message -----
From: <rob@xxxxxxxxx>
To: "RPG programming on the AS400 / iSeries" <rpg400-l@xxxxxxxxxxxx>
Sent: Thursday, July 22, 2004 10:35 PM
Subject: Re: Service Programs 101


>
>
> Dave,
>
> You want to look at an intense binding directory?
> WRKBNDDIRE BNDDIR(QC2LE)
> This is the key to numerous cool functions like system(), etc. And some
> ones I don't often see in RPG like arctangent. I did some brief scanning
> for the documentation on QC2LE but can't really find it. If you want you
> can do the following for every service program in the binding directory:
> DSPSRVPGM SRVPGM(...) DETAIL(*PROCEXP *DTAEXP)
>
>
> You can do the following to specify multiple binding directories:
> H Bnddir('ROUTINES/SRVPGM':'QC2LE')
>
> In fact my typical H spec in my programs has the following:
> /DEFINE HSpec
> /INCLUDE ROUTINES/QRPGLESRC,HSPEC
> /UNDEFINE HSpec
>
> and ROUTINES/QRPGLESRC,HSPEC has
> /DEFINE HSpec
> /COPY ROUTINES/QRPGLESRC,HSPEC2
> /COPY ROUTINES/QRPGLESRC,HSPEC1
> /UNDEFINE HSpec
>
> and ROUTINES/QRPGLESRC,HSPEC1 has
> /DEFINE HSpec
> H Bnddir('ROUTINES/SRVPGM':'QC2LE')
> H ActGrp(*CALLER)
> H DftActGrp(*NO)
> /UNDEFINE HSpec
>
> and ROUTINES/QRPGLESRC,HSPEC2 has
> H Datfmt(*USA)
> H Copyright('(C) Copyright Group Dekko Services, LLC')
> H ExprOpts(*RESDECPOS)
> H* EXTBININT will change (B)inary to (I)nteger.
> H EXTBININT(*YES)
>
> Why did I break apart HSPEC1 and HSPEC2? Because in my service programs I
> do not use HSPEC. I only use HSPEC2.
>
> Hey, who was it that asked about the eval statement crashing about the
> variable size recently? Would ExprOpts(*RESDECPOS) have been applicable to
> them?
>
> Rob Berendt
> --
> Group Dekko Services, LLC
> Dept 01.073
> PO Box 2000
> Dock 108
> 6928N 400E
> Kendallville, IN 46755
> http://www.dekko.com
>
>
>
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> |   daparnin@xxxxxxxxxxxxxxxxx|
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> |   rpg400-l-bounces@midrange.| rpg400-l@xxxxxxxxxxxx
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> |   com                       |
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> |   07/22/2004 04:00 PM       |
Subject|
> |                             | Re: Service Programs 101
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> |         Please respond to   |
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> |      RPG programming on the |
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> |          AS400 / iSeries    |
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> |      <rpg400-l@xxxxxxxxxxxx>|
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> |                             |
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> |                             |
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>
>
>
>
>
>
>
>
>
>
> Rob, Buck, Joel, & Scott,
>
> Wow. Thanks for the education and encouragement. The good news is that I
> created a binding directory, did a ADDBNDDIRE to it for the service
> program, added an BNDDIR ('BNDNISCO') H-spec to my RPG, and it compiled!!!
> I'm almost afraid to say that it made sense. This might be a low-wattage
> lightbulb moment. Right now I'm at only about 15 watts but I'll try to get
> to 60. I agree that this would be a good topic for a FAQ (and I did look
> for an explanation in the FAQ's before I posted).
>
> Buck suggested creating a single binding directory for all of the
> developers here to use (that would be me). Since the system allows you to
> create multiple binding directories will it cause problems to have more
> than one or is it that there's no real need to have more than one? It
> looks to me like it's an index that tells where to find service programs.
> If that's the case then it wouldn't hurt to have multiple binding
> directories that could possibly have the same service program listed in
> them, it would just be confusing and you might have to search a bit to
find
> the correct one. (And trust me--I have enough confusion in my life
> already.)
>
> I started to look at your tutorials Joel. It looks like there's good stuff
> there. I will definitely read them as you suggested. I've been reading
> Scott's IFS and Sockets tutorials and have learned a lot with them. In the
> past year I've made the jump to RPG IV, and /Free, so I might as well keep
> on going with modules and service programs. I'm learning the stuff now
> partially because I'm working on projects that involve sockets and the IFS
> although those could have been accomplished without service programs. I've
> learned RPG IV, /Free, and now service programs because they have been
used
> in IBM manuals, posted examples, and tutorials. If they hadn't been there
> where I could start examining them I probably wouldn't have bothered. But
> that's a topic outside of this list...
>
> Thanks!
>
> Dave Parnin
> Nishikawa Standard Company
> Topeka, IN 46571
> daparnin@xxxxxxxxxxxxxxxxxx
>
>
>
>
>
> Buck Calabro
> <buck.calabro@comm To: rpg400-l@xxxxxxxxxxxx@SMTP@CTB
> soft.net> cc: (bcc: David A Parnin/Topeka/NISCO/SPCO)
> Sent by: Subject: Re: Service Programs 101
> rpg400-l-bounces@m
> idrange.com
>
>
> 07/22/2004 02:35
> PM
> Please respond to
> RPG programming on
> the AS400 /
> iSeries
> <rpg400-l@midrange
> .com>
>
>
>
>
>
> Dave wrote:
>
> > This should be a quick one for most of you.
>
> On the contrary. Often, the easiest questions to ask are the hardest
> to answer.
>
> > What exactly is a service program,
>
> A service program is a collection of procedures intended to be used by
> (mainline) programs.
>
> > I am familiar with creating RPG modules
> > and then binding them into a executable program.
>
> That may be the same thing depending on how you then call the code in
> the bound modules. If you use eval [as in eval
> myResult=someFunction(aParameter)] or callp [as in callp
> someFunction(aParameter: aNotherParameter)], then changing the bound
> module to a service program is a pretty easy step to take.
>
> > The service program was successfully created in QGPL.
> > I'm using a /COPY member of Scott's to define the procedure.
> > I get the following error when I try to do a CRTBNDRPG
> > on my program. Do I need to create my program as a module
> > and then bind it to the service program?
> >
> > MY ERROR MESSAGE:
> > Message . . . . : Definition not found for symbol 'READLINE'.
>
> You're close... Let me start at the error and work backwards.
> "Definition not found' means that the binder (the BND part of
> crtBNDrpg) cannot find any PI reference in your (single) module. The
> compiler part (CRTbndRPG) didn't have a problem because the /COPY
> defined what the prototype looks like. The reference to READLINE in
> the mainline was understood by the compiler because it had seen a
> prototype for READLINE.
>
> Why did the binder not find the PI? Because no where on CRTBNDRPG is
> there a way to specify the location of the PI - the actual procedure
> definition. That's in the service program. You should double check
> that by doing a DSPSRVPGM and making sure the READLINE procedure is
> exported. You can tell the binder how to find the service program
> (and therefore the PI) in several ways.
>
> One way is to do a two-step compile & bind, similar to what you do
> when you bind two modules together. CRTRPGMOD on your mainline, and
> then CRTPGM and instead of specifying the service program in the
> MODULE parameter, you specify it in the BNDSRVPGM parameter. This
> will work for the moment, but I think that many people find it
> inconvenient to do two steps to make a program.
>
> Another way is to use an object called a binding directory. If you go
> back and look at the CRTBNDRPG command, you'll see that there's a
> parameter called BNDDIR. You specify the name of the binding
> directory you're about to create on that parameter and you can compile
> in one step - the familiar PDM option 14.
>
> What's a binding directory? Oops... guess I should detour a moment to
> describe it. A binding directory is a search path for procedures.
> Like a library list or classpath or DOS PATH. When the binder can't
> find a PI (like READLINE) it looks at the first entry in the binding
> directory. Say the first entry is a service program: the binder looks
> at all the exports for that service program and sees if any are
> READLINE. If so, it binds to that service program and goes on to the
> next 'definition not found.'
>
> Create a binding directory - as a beginner, may I suggest that you
> create one single *BNDDIR for your whole company? Let's call it
> NISHIKAWA. Put it in a library where every developer can use it, say
> QGPL or QUSRSYS. All you need to do now is to add a binding directory
> entry, something like ADDBNDDIRE BNDDIR(NISHIKAWA) OBJ((SCOTTSRVPG
> *SRVPGM)) Your needs may differ, but you probably want the service
> program to be *LIBL and not qualified... Now you have a way for the
> binder to search for READLINE.
>
> So you can now compile with option 14 and BNDDIR(NISHIKAWA), but
> that's a pain, isn't it? You can make it even easier, because the
> compiler recognises the H specification keyword BNDDIR! So you can
> put H bnddir('NISHIKAWA') at the top of your program, compile with PDM
> 14 and never bother with prompting the command.
>
> Give it a whirl, see how it feels and let us know if any of this
> advice was worth reading. We can try to make a FAQ entry out of it to
> help others who are just starting out with this stuff. In this
> regard, your feedback is crucial, because you're just stepping on that
> first stair. Some of us are already standing on that stair and have
> forgotten what was so new and different about service programs.
> --buck
>
>
>
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