More problems w/passing data structures as parameters

Hi,
      I appreciate all the help I have gotten from the list so far, but I
have another problem.  I am passing a data structure as a parameter to a
procedure, and when I execute a shell program to test it, I get the message
'Pointer not set for location referenced' & 'Pointer or Parameter error
(CGDF). I am trying to follow an example I found in the Club Tech
Newsletter, and I can't see where I went wrong. All the modules and the
shell compiled OK, and the CRTPGM was OK.  Any and all advice is greatly
appreciated.

This is the /copy I am using (PROINV)

   // ---------------------------------------------Prototype: DescClass
 D DescClass       PR              N
 D  ItemInfoDS                         LikeDS(ItemInfo)
 D ItemInfo        DS                  Based(ItemInfoPtr)
 D  ItemIn                       15
 D  DscOut                       30
 D  ClsOut                        2

This is the inventory procedure (DESCCLASS)

H  NOMAIN
 *  External procedure for DESCCLASS

 /COPY QPROSRC,PROINV

  ////////////////////////////////////////////////////////////////////
  //  Procedure to return the description & item class for an item.

PDescClass        B                   EXPORT
D DescClass       PI              N
D  ItemInfoDS                         LikeDS(ItemInfo)
D*
D IDESC           S             30    INZ(*blanks)
D ICLAS           S              2    INZ(*blanks)
C*
C/EXEC SQL
C+ SELECT idesc, iclas INTO :idesc, :iclas FROM iim WHERE iprod =
C+ :ItemIn
C/END-EXEC
C*
C                   Eval      DscOut = IDESC
C                   Eval      ClsOut = ICLAS
C                   Return    *off
C*
PDescClass        E

And this is the shell program I am executing

 /If Defined(*CRTBNDRPG)
H DftActGrp(*NO) ActGrp(*Caller)
 /EndIf

F*   Shell program to test inventory procedures.
D*
D Main            PR                  EXTPGM('SHELLINV')
D                                2
D                               15
D*
D Main            PI
D  ParmItm                      15

 /COPY QPROSRC,PROINV

D ReturnMPG       S              5
D ReturnDS        S             47
D ReturnInd       S               N
D ItemInfoDS      S                   Like(ItemInfo)

 /FREE

  Eval ItemIn = ParmItm;
  Eval DscOut = *blanks;
  Eval ClsOut = *blanks;
  ReturnInd = DescClass( ItemInfoDS );
  Dsply ItemIn;
  Dsply DscOut;
  Dsply ClsOut;

  *INLR = *ON;
  Return;

 /END-FREE

<===================================================>

Terri Harteau
Felker Brothers Corp.
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"There's no point in being grown up if you can't be childish sometimes."
- Dr. Who
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