How to debug SQL UDF

After visiting the archives, the SQL reference manual, the IBM DB2 web site,
the AS/400 newsgroup and the April 2000 Midrange Computing article I am
still stuck trying to debug a UDF.  I can't get it to break when I put it in
debug mode, and a DUMP operation tells me that "Variable data is not
available in a secondary thread. "  I created my function with:

CREATE FUNCTION STRLEN (CHAR) 
RETURNS INTEGER               
RETURNS NULL ON NULL INPUT    
LANGUAGE RPGLE                
EXTERNAL NAME 'BUCK/SQLUDFLEN'
DETERMINISTIC                 
NO SQL                        
NO EXTERNAL ACTION            
PARAMETER STYLE SQL           
DISALLOW PARALLEL             

Isn't "disallow parallel" supposed to suppress multi-threaded operation?

d inpChar         s            256            
d outLen          s             10i 0         
d inpInd          s            256            
d outInd          s            256            
d outSQLState     s              5            
d inpFuncName     s            139    varying 
d inpSpecName     s            128    varying 
d outDiagTxt      s             70    varying 

c     *entry        plist                                
c                   parm                    inpChar      
c                   parm                    outLen       
c                   parm                    inpInd       
c                   parm                    outInd       
c                   parm                    outSQLState  
c                   parm                    inpFuncName  
c                   parm                    inpSpecName  
c                   parm                    outDiagTxt   
                                          
c                   eval      outLen = 55 
c                   dump                  
c                   eval      *inlr = *on 

I also tried setting my QAQQINI to PARALLEL_DEGREE *NONE to no avail.  In
debug I get the message "Breakpoint received in secondary thread."
For what it's worth, the return value shows as 55 on my interactive SQL:
select strlen(name) from master where name like 'B%' so I know the program
works.  I just want to see it in debug!

Buck Calabro
Aptis; Albany, NY
"Nothing is so firmly believed as
 that which we least know" -- Michel Montaigne
Visit the Midrange archives at http://www.midrange.com
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