This is a basic template for an Open Access handler program. I developed it after I had written a number of other examples which is why you will find some of the techniques used slightly different and, hopefully, easier to follow.

	

     H DftActGrp(*No) Option(*SrcStmt)

       // User Data - normally in a copy source - modify as required
     D userData_T      ds
     D   userParm                    10a

        // Standard IBM supplied Open Access definitions
      /Copy QRNOPENACC

        // Copy constants for all RPG status codes - write your own or use mine
        //   email me at Contact at Partner400 dot com if you would like a copy
      /Copy MonStatCds

       // Protos for program and local procedures - not needed v7+
     D OpenFile        Pr

     D CloseFile       Pr

                                        // Change to ExtProc etc. if required
     D HandlerName     Pr                  ExtPgm('HANDLERNM')
     D   info                              likeds(QrnOpenAccess_T)


     d userData        ds                  Based(info.userArea)
       // Add fields as required - normally this is in a /Copy

       // Remove input and output buffer definitions if not needed
     d inputBuffer     s          64512a   Based(info.inputBuffer)
     d outputBuffer    s          64512a   Based(info.outputBuffer)

      // Field Names/Values structures if required
     D nvInput         ds                  likeds(QrnNamesValues_T)
     D                                     based(info.NamesValues)

       // State info
     d stateInfo       DS                  Based(info.stateInfo) Qualified
       // Add the data defintions for whatever fields you need preserve for a specific file

     D RcvDQHand1      PI
     D   info                              likeds(QrnOpenAccess_T)

      /Free

       Select;

         // Add When clauses here for all required operations
         //   READ, CHAIN, SETLL, etc. - Whatever you need

         When (info.rpgOperation = QrnOperation_OPEN);
           OpenFile();

         When (info.rpgOperation = QrnOperation_CLOSE);
           CloseFile();

         Other; // We don't know how to do this operation
           Dsply ('Unsupported function ' + %Char(info.rpgOperation)
                 + ' on queue ' + info.externalFile.name );
           info.rpgStatus = errIO;

         EndSl;

       Return;
      /End-Free

       // Basic outline logic for Open function
     P OpenFile        B
     D                 PI

      /Free
       // If no state info area yet allocate now and initialize
       If info.stateInfo = *null;
         info.stateInfo = %Alloc( %Size(stateInfo));
         Clear stateInfo;
       EndIf;

       // Check if user parm was supplied and any set defaults if needed
       //   Store the values in the state info area oitherwise if values change
       //   in the user parm it migth really mess us up
       If info.userArea = *Null;
         // Set any default values required by handler
       Else;
         // Copy user supplied data into state info area to preserve
       EndIf;

       Return;

      /End-Free

     P OpenFile        E


     P CloseFile       B
     D                 PI

      /Free

       // Release storage holding state information and set pointer to null.
       //   That way we can't ever reference it by mistake.
       Dealloc info.stateInfo;
       info.stateInfo = *null;
       info.rpgStatus = stsOK;

       Return;

      /End-Free

     P CloseFile       E

 

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