Re: Using opdesc ... getting CEE0502

[Rory Hewitt <rory.hewitt@xxxxxxxxx>]

Mark,

It's the difference between simply recompiling a source member and adding
code to each one to calculate the length and then recompiling it.

Depending on the procedures and change management system David uses (I
suspect I know which one!), there may be less testing required if all that's
changed is the OPDESC keyword on the prototype.

Rory

On Wed, Mar 24, 2010 at 10:32 AM, Mark S. Waterbury <
mark.s.waterbury@xxxxxxx> wrote:

> Hi, David:
>
> So, you had to change the prototype for your "procname" procedure to
> include "opdesc", yes?  Therefore, you would have to (at a minimum)
> recompile every other program that includes this prototype, because the
> compiler has to _generate extra code_ to pass those operational
> descriptors in the first place... otherwise, there is nothing there for
> CEEDOD to retrieve. .. and, hence, your original error CEE0502 ... and
> so indeed, there IS NO operational descriptor being passed... :-o
>
> So, since you will have to recompile all of the callers anyway, and this
> is all part of a product for which you have control over the source
> code, then why not just make the changes I suggested in the first place?
> ;-)
>
> Mark
>
>  > David Gibbs wrote:
> > Mark S. Waterbury wrote:
> >
> > > Why not just pass one more parameter to your "procname" procedure, with
> > > the size of that other parameter (in this case, a data structure)?
> >
> > That requires that I change the caller ... which I would like to avoid.
> >
> > Using opdesc should let me determine the length of the variable being
> passed in.
> > > There is some "overhead" when using operational descriptors ...
> >
> > There's overhead in everything ... IMO the flexibility of opdesc
> outweighs the performance hit.
> > > I can understand using CEEDOD with some APIs or "exit points" of some
> > > other vendor product, over which you have no control, and when the
> > > source code might not even be provided or available.  But, to use it
> > > within your own code, or as a part of product(s) you are supporting and
> > > maintaining or enhancing,  I am not sure this is really such a "good
> > > idea"...  _unless_ you are creating "APIs" that your customers will be
> > > calling?
> >
> > My routine is called from a number of locations in my code ... not all of
> which I am currently modifying.  It's much easier to change the internals of
> a routine than the prototype.
> > david
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