How to copy a multi occurrence DS to another DS RPG

Question

I am trying to copy a DS to another DS.

D  MYRESULTS      DS                  OCCURS(2000)
 D                                     QUALIFIED
 D  PAOPIID                      20A
 D  POPITPE                      10A
 D  POPISTPE                     10A
 D  POPIKNID                     20A
 D  PINSTAT                      10A
 D  PLEAFIND                      1A
 D  CLOPIID                      20A
 D  COPITPE                      10A
 D  COPISTPE                     10A
 D  COPIKNID                     20A
 D  CINSTAT                      10A
 D  CLEAFIND                      1A
 D  INSTAT                       10A

 D  MYRESULTS2     DS                  OCCURS(2000)
 D                                     QUALIFIED
 D  PAOPIID                      20A
 D  POPITPE                      10A
 D  POPISTPE                     10A
 D  POPIKNID                     20A
 D  PINSTAT                      10A
 D  PLEAFIND                      1A
 D  CLOPIID                      20A
 D  COPITPE                      10A
 D  COPISTPE                     10A
 D  COPIKNID                     20A
 D  CINSTAT                      10A
 D  CLEAFIND                      1A
 D  INSTAT                       10A 

So I want to copy MYRESULTS into MYRESULTS2 without looping MYRESULTS and processing each element to copy it to MYRESULTS2 .

I did try just assigning it.

 MYRESULTS2 = MYRESULTS;
       %OCCUR(MYRESULTS2) =  3 ;
        opsitem =  %TRIM(MYRESULTS2.PAOPIID);
       PrintLine =opsitem ;
       Except;

The first occurrence works... but it does not copy the rest ie. occurrence 3.

I did get it working by looping MYRESULTS and for each occurrence copied it to MYRESULTS2 .

Is there a faster way to assign all the occurences from MYRESULTS to MYRESULTS2

V6.1 - IBM

Answer 1

I would firstly suggest that you start using dim instead of occur for arrays. Because then it would be a simple one line eval statement.

Anyways you could use the C++ function MEMCPY for the fastest result (assuming that both data structures are exactly the same format and dimensions):

 hdftactgrp(*no) actgrp(*new)

 dMEMCPY           pr                  extproc('memcpy')
 d TargetPointer                   *   value
 d SourcePointer                   *   value
 d CopyLength                    10u 0 value

 dSample1          ds                  qualified occurs(10)
 dNumber                          3p 0
 dValue                          10a
 dSample2          ds                  qualified occurs(10)
 dNumber                          3p 0
 dValue                          10a

 dresult           s              1a
  /free
   %occur(Sample1) = 1;
   Sample1.Number = 1;
   Sample1.Value = 'One';
   %occur(Sample1) = 10;
   Sample1.Number = 10;
   Sample1.Value = 'Ten';

   %occur(Sample1) = 1;
   %occur(Sample2) = 1;
   MEMCPY(%addr(Sample2): %addr(Sample1): %size(Sample1) * %elem(Sample1));

   %occur(Sample2) = 10;

   dsply Sample2.Value '*EXT' result;

   *inlr = *on;

  /end-free 

Answer 2

I got it working using a pointer to the DS.

 D Mypointer       s               *

 D  MYRESULTS2     DS                  OCCURS(2000) based(Mypointer)
 D                                     QUALIFIED
 D  PAOPIID                      20A
 D  POPITPE                      10A
 D  POPISTPE                     10A     

And then when you want to assign it.

 Mypointer = %ADDR(MYRESULTS);

After this you are able to use all the occurrences in the DS