Re: Parameter passing CL to RPGLE

[Peter Dow <petercdow@xxxxxxxxx>]

Interesting that the compiler doesn't complain about the unqualified 
name.  If the pointer were set to some valid data but not the *ENTRY 
parameter, which field would the compiler use when the field reference 
is unqualifed?


On 10/7/2016 1:01 PM, CRPence wrote:
> You can effect nearly identical to what TEMPLATE provides, using 
> BASED, as shown here.  Note that the QUALIFIED keyword is *not* 
> required to be specified; although unqualified references will be 
> problematic if the basing pointer is not set correctly; oddly, I do 
> not get a MCH3601 on v6r1 [but I do on v5r3, and msg CPF8E17 when EVAL 
> @MODE] when the basing pointer is initialized to *NULL as shown, and 
> instead get INCORROUT UNPRED (UR) results -- but the code shown here 
> sets the pointer to the address of the by-reference-pointer 
> *immediately* upon entry:
>
>     d  ptrToData      s               *   inz(*NULL)
>     d  @PARMS       e DS                  extname(OB0050PR)
>     d                                     based(ptrToData)
>
>     d  OB0050AN       pi
>     d  @RETURNCODE                   2A
>     d  @CALLER                      10A
>     d  PARMS                              likeds(@PARMS)
>     d  c111           s            111A
>
>      /free
>          ptrToData = %addr(PARMS) ;
>
>        // The following, if un-commented, are function equivalents:
>        //  if parms.@mode = 'B' ;
>        //  if @MODE = 'B' ;
>
>   Thus, for the same reason those two predicates are the /same/, the 
> SQL can be written as shown here, thus avoiding a qualified name that 
> would prevent the pre-compiler from functioning as desired:
>
>      UPDATE myTable SET myColumn = :@MODE WHERE ...