RE: passing pointers

[Joel Fritz <JFritz@xxxxxxxxxxxxxxxx>]

Ok, I get that.  My question is what "really" happens when you pass a
pointer by _reference_, as in a dynamic call, and base a field in the
receiving program on that pointer?  What actually happens is that the field
in the calling program that is tied to pointer can be updated when the
called program changes the value in its based field.  Seems like the
dereferencing and indirection are out of sync.  See my response to John Carr
which I posted just before this, but which may come in after this for a more
detailed and confusing exposition.         

> -----Original Message-----
> From: Jon.Paris@hal.it [mailto:Jon.Paris@hal.it]
> Sent: Tuesday, November 28, 2000 6:49 PM
> To: RPG400-L@midrange.com
> Subject: Re: passing pointers
> 
> 
> 
>  >> I guess the real question is, how are pointers passed as 
> parameters?
> 
> Passing a pointer to a field by value is the same as passing the field
> itself by reference.
> 
> So the following two calls are equivalent:
> 
> 
>      D MyField         S             20a
> 
>      D ByValue         Pr
>      D  ValParm                        *   Value
> 
>      D ByReference     Pr
>      D  RefParm                            Like(MyField)
> 
>      C                   CallP     ByValue(%Addr(MyField))
>      C
> 
>      C                   CallP     ByReference(MyField)
> 
> 
> In both cases a pointer is received by the called procedure.
> 
> 
> 
> 
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