Re: Changing a service program

Hi, Vern,

When "P" gets activated into any AG in your job, at that time, it 'resolves' to the address of "S" and also resolves pointers to any procedures (entry points) in that *SRVPGM.  Those pointers are now loaded in the "working storage" of "P" ... in its AG.

Hence, when you recompile "S"  if "P" is already activated, those copies still have pointers to the old "S" (now in QRPLOBJ).

You can sign-off and sign-on or issue RRTJOB to "clean up" all AGs and reset the job to the way it was when you first signed on.

Hope that helps,

Mark S. Waterbury

On Sunday, November 17, 2019, 9:18:02 AM EST, Vernon Hamberg <vhamberg@xxxxxxxxxxxxxxx> wrote:

Hi Joep

I think the same thing is done with P as with S - IF it is in use when
it is recreated. That's been my understanding, that objects can be
recreated without interrupting work - but the work will use the object
before it was changed.

So the job using program P would still not see the new S, since it is
still using the old P.

Now someone who knows better than I can straighten me out, please!!

Regards
Vern

On 11/17/2019 7:44 AM, Joep Beckeringh via MIDRANGE-L wrote:

When I think I understand something about RPG and Barbara claims she
doesn't, it is time to start worrying :-)

This is how I understand it:
- When program P, which uses service program S, is activated, S is
located and P receives pointers to the procedures it uses;
- When service program S is recreated, the old version is moved to
QRPLOBJ; P keeps the pointers to the old version in QRPLOBJ; thus it
doesn't "see" the new version;
- When program P is recreated and activated, S is located and so the
new P receives pointers to the new S; and thus it "sees" the new version.

Am I wrong in my understanding?

Joep Beckeringh


Op 16-11-2019 om 14:17 schreef Barbara Morris:

On 2019-11-15 10:01 p.m., smith5646midrange@xxxxxxxxx wrote:

...
What I still don't understand is that I didn't add or remove any
procedures.  I only modified the code within an existing one but the
changes won't execute until I recompile the program.  I thought the
idea of a service program is that you could make changes (if you
found a bug for example) and not have to recompile everything that
used it because it would automatically pick up the new version.  Is
there a restriction that if you change an existing function that you
have to recompile all of the calling programs?

I also thought the service program was not bound into the program
(like a module would be) but when I deleted the service program, the
program still ran.
...

When a service program has been used in an activation group, the
activation group "remembers" the service program. If you change the
service program, the change won't be noticed by anything in the
activation group. (It might be "anything already in the activation
group, which would explain why recompiling the program made it see
the new version of the srvpgm, but I don't really understand how that
aspect of activation groups works.)

When you change a service program, you _could_ (but shouldn't)
reclaim the activation group. I say "shouldn't" because reclaiming
activation groups can sometimes cause strange problems if other
activation groups have hooks into the reclaimed one.

So I find it's safer, and easier in the long run, to just sign off
and sign back on again.