Re: Ending a program from within a procedure -- RPG400-L

I have a situation where I Monitor for an error.  When the error occurs,
I want to send a message and then terminate the program.
But... how do I terminate the program from within a sub-procedure?

You can't end a program (normally) from a subprocedure. You can end itabnormally by issuing an escape message when an error occurs, though.

Personally, I've found that it's better not to try to end the program froma subprocedure. A subprocedure should have one job -- it should do onething, and return the results to the caller. If it ends the program, thenit's doing two things, both it's original purpose, AND controlling theflow of the program.

I've found that it works better when the main procedure's only job is tocontrol the flow of the program, and the subprocedure's jobs are tocarry out steps that the program takes, and then return the results to themain procedure.

*InLR = *On;
Return;
from the main procedure.  But doing that in a subprocedure simply
returns control to the caller.

You think this is futile from the perspective of a subprocedure? Try itin a separate module or service program. In that case, you won't even seton *INLR, since there's a separate one in each module.

Instead, your subprocedure should return an error saying it can't dowhatever it was intending to do. It should not be in charge of ending theprogram.

Do I need to code an exit path in?
ie.
procedureCall( parm );
If not *InLR;
 continue normal code.
EndIf;

Yes, but using a global variable (in this case, *INLR) to indicate thatthe program should end is just stupid. Return an error value of somesort. Either make the return value from procedureCall() indicate successor failure, or have a parameter that indicates it.

I like to use an indicator as a return value, and have constants thatindicate success or failure. For example:


     D SUCCESS         c                   '1'
     D FAIL            c                   '0'

     D procedureCall   PR             1N
     D    parm                       10A   const

      /free
              *inlr = *on;

              .
              .

              if ProcedureCall(parm) = FAIL;
                 return;
              endif;

              .
              .

              return;

      /end-free

Note that I also set on *INLR at the very start of my program. You aren'tusing the cycle, are you? If not, then why bother ever having *INLRturned off? By setting it on at the top of my calcs, I can end theprogram with one line of code -- just the RETURN statement.

I'd hate to have to do this after every procedure call that has a
Monitor in it.

It's really not that big of a deal... The routines are much more reusablewhen you let the caller decide the flow, rather than the subprocedure. Theextra line or two of code isn't a big deal.

But, like I said, if you're really want to end the program from asubprocedure, send an escape message -- or, since you're monitoring forone already, re-send that one.