Re: Using opdesc ... getting CEE0502

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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