Re: Passing By Reference

["JJW" <rpgilejjw@xxxxxxxxxxx>]

I've made the changes mentioned by Scott, Bob, Gary, Buck,
and others.

It is finally working!!!

When I run the procedure through the debugger I find that
the last value of the field passed to the procedure when
returned has a hex value contained in the last position of
the field.  The character looks like a little arrow
pointing down and to the left, I assume it's some hex
value.  Is this any reason for concern?

Thanks to everyone for all their time and effort!!!

John



On Mon, 25 Nov 2002 16:46:00 -0600 (CST)
 Scott Klement <klemscot@klements.com> wrote:
> This line is wrong:
>     F1 = %replace('':F1:%scan(C1:F1):1);
>
> It is setting all 32766 characters of F1.   This is a
> problem because F1
> may not be that long, and therefore, it will be
> overwriting memory that
> it should not be.
>
> Also, the RETURN statement:
>
>      Return F1;
>
> This is copying 32766 bytes from the start of F1 to make
> a return value.
> That's not good because you're reading from memory past
> the end of the F1
> parameter if it's not the full size.
>
> Not only that, but since F1 is passed by reference, it
> really doesn't
> make much sense to use it as a return value.   You've
> already got the
> result in the calling procedure... returning it makes
> another copy of
> it as well.   If you are assigning that return value back
> to the same
> variable, you'll cause some nasty problems.
>
> So, here's what I'd do:
>
>     1) Change the F1 = %replace() line to be
> %subst(F1:1:InLen) =
>                %replace(etc).
>     2) Remove the RETURN statement.
>     3) Remove the return value from your Prototype (PR)
> statement
>     4) Remove the return value from your Procedure
> Interface (PI)
>                statement
>
> See if that works...