RE: passing parameters longer than expected

Charles, that is helpful, thanks.

-----Original Message-----
From: rpg400-l-bounces@xxxxxxxxxxxx [mailto:rpg400-l-bounces@xxxxxxxxxxxx] On Behalf Of Charles Wilt
Sent: Wednesday, March 28, 2012 8:01 AM
To: RPG programming on the IBM i / System i
Subject: Re: passing parameters longer than expected

Nope, when CONST is used, the parameter is indeed passed by reference (ie. the 16 byte address of the variable is passed).

The key is to understand that when CONST is specified, if needed the compiler creates a temporary variable, 40a in this case and passes the address of that temporary variable.

It is usually sufficient to simply imagine CONST always creates such a temporary variable. As in the case of Joe's example.

However, as Barbara mentions, in the case of your variable being longer than the parm, the compiler doesn't actually need to create a temporary variable so the address passed is that of your original variable.

HTH,
Charles

On Wed, Mar 28, 2012 at 9:33 AM, Gary Thompson <gthompson@xxxxxxxxxxx> wrote:

Dave, and Barbara, I thought I was following this thread, but now I am
confused and have a question:

Earlier, Joe stated:
       "By specifying CONST you specifically told the compiler to
ignore any
       data past the 40A; in effect, you asked it to do a MOVEL (or
EVAL) of
       your 100A into a temporary 40A field and call with it."

I >think< that means the parameter passed would be more like "by value"
       because the called program has no >reference< to the 40A memory.

If "by constant reference", works as described above, why is the word
       >reference< used ?

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