RNF7701 - Data structure not allowed

Hi all,

I'm getting a compile error on what looks like OK code to me.  I've
stripped the program down as small as possible to demonstrate the error,
which happens to occur on a V5R2 machine.

What I want to do is load the WMERLG record format fields, then, locate
the highest EID in the file, add one to it, and attempt to use it for
the new record key.  I don't want the 'next_eid' routine to clobber the
E* fields, hence the need for reading into a data structure.

Here is the file, WMERLGP:
     A                                      UNIQUE
     A          R WMERLG
     A            EID           11P 0
     A            EACCT#        11P 0
     A            EAPLNM        20A  
     A            EAPFNM        12A  
     A            EAPITL         1A  
     A            EVISDT          Z  
     A            EREVDT          Z  
     A            EUSRID        10A  
     A            ERSTS          1A  
     A          K EID

And the code:
     H dftactgrp(*no) actgrp(*caller)
     H OPTION(*SRCSTMT:*NODEBUGIO)

     FWMERLGP   if a e           k disk

     d Q             e DS
EXTNAME(WMERLGP:WMERLG:*INPUT)
     d                                     QUALIFIED

     d next_eid        pr            11s 0
     d $err            s               n

      /free
         $err = '0';
         dow $err = '0';
             EID = next_eid();
             write(e) WMERLG;
             $err = %error;
         enddo;
         *inlr = '1';
      /end-free

     p next_eid        b
     d next_eid        pi            11s 0

     d result          s             11s 0

      /free
         setgt *hival wmerlgp;
         // read into a ds so as not to disturb the
         // global file fields
         readp wmerlg Q;
     // RNF7701 here!
         if %eof(wmerlgp);
             result = 1;
         else;
             result = q.eid + 1;
         endif;
         return result;
      /end-free
     p                 e


The error is RNF7701, 'Data structure is not allowed for the operation',
and lists the line of code that does 'readp wmerlg Q'.

I've tried EXTNAME(WMERLGP), EXTNAME(WMERLGP:*INPUT),
EXTNAME(WMERLGP:*OUTPUT) and also with and without the 'QUALIFIED',
still get the error.

PS - I tried to put the code on the code.midrange.com app
(http://code.midrange.com), but I receive the following error, 'Access
denied for user 'nopaste'@'localhost' (using password: YES)'

If you have any ideas, let me know, please.

Thanks.

Regards,
Rich