Is Powerpoint still a single instance app?

"Mike M." wrote in message
...
My app has been doing what Steve suggests for almost 4 years without any
reports of problems. There is one and only one instance of Powerpoint
(powerpnt.exe) running regardless of how many programs have a reference
count to it or if a user opened the GUI for Powerpoint. I check to make
sure that presentations count = 0 then I call the Powerpoint quit method.
If a user has started the GUI and closed the pres1 (or whatever) default
presentation Powerpoint creates then indeed when you quit PowerPoint it
closes the GUI. If other programs have connected to that instance of
Powerpoint then they would get an exception when they referenced that
object. But that is why there is a big disclaimer on the MS web site that
tells us not to use Powerpoint in an automated fashion. We are pretty
much
out there on our own. I had originally hoped they would expose the
reference count through a method or property but I didn't see it.

It seems that the problem can be solved by enumerating processes.

----------------------------
I was using the wrong terminology.

PowerPoint is a Multi-use, single Instance app.

I guess I'm not grasping the meaning of Multi-use in this context.

see kb article 288902

--
http://www.standards.com/; See Howard Kaikow's web site.
"Steve Rindsberg" wrote in message
...

----------------------------
I was using the wrong terminology.

PowerPoint is a Multi-use, single Instance app.

I guess I'm not grasping the meaning of Multi-use in this context.

In article , Howard Kaikow wrote:
288902


Thanks, Howard. That still leaves me puzzled, though.

It refers to "Instancing" as having one of two values, Single- or MultiUse. It
doesn't refer to Instancing as a property distinct from those two.

And either I'm missing the kick in the head that triggers the AHA or the
article is wrong. It says:

"Depending on whether the server is designed as SingleUse or MultiUse, another
server process may or may not be launched." It doesn't say which is which, but
it seems reasonable to assume that "MultiUse" = "another server may be
launched".

It then goes on to say that Excel and Word are SingleUse, which doesn't seem
right to me. Rather, it seems to have reversed the values.

It does raise an interesting point that reinforces your thoughts, though:
we've been talking about user- and your_code-initiated instances of PPT, but
there might also be an instance initiated by the user or code activating a PPT
object (slide or presentation) from within another app.

The fun never ends. ;-)

If it's possible to identify and stop individual processes independent of the
application instance itself, it sounds as though you're onto a possible
solution to the problem.

-----------------------------------------
Steve Rindsberg, PPT MVP
PPT FAQ: www.pptfaq.com
PPTools: www.pptools.com
================================================

Steve, I think this terminology goes against the grain. Sort of like
Unicast and Multicast in streaming video. MultiUse means that multiple
users attach to the single instance server. SingleUse means each user gets
their own instance of the server. AHA?



"Steve Rindsberg" wrote in message
...
In article , Howard Kaikow wrote:
288902


Thanks, Howard. That still leaves me puzzled, though.

It refers to "Instancing" as having one of two values, Single- or
MultiUse. It
doesn't refer to Instancing as a property distinct from those two.

And either I'm missing the kick in the head that triggers the AHA or the
article is wrong. It says:

"Depending on whether the server is designed as SingleUse or MultiUse,
another
server process may or may not be launched." It doesn't say which is
which, but
it seems reasonable to assume that "MultiUse" = "another server may be
launched".

It then goes on to say that Excel and Word are SingleUse, which doesn't
seem
right to me. Rather, it seems to have reversed the values.

It does raise an interesting point that reinforces your thoughts, though:
we've been talking about user- and your_code-initiated instances of PPT,
but
there might also be an instance initiated by the user or code activating a
PPT
object (slide or presentation) from within another app.

The fun never ends. ;-)

If it's possible to identify and stop individual processes independent of
the
application instance itself, it sounds as though you're onto a possible
solution to the problem.

-----------------------------------------
Steve Rindsberg, PPT MVP
PPT FAQ: www.pptfaq.com
PPTools: www.pptools.com
================================================

"Steve Rindsberg" wrote in message
...
In article , Howard Kaikow wrote:
288902


Thanks, Howard. That still leaves me puzzled, though.

It refers to "Instancing" as having one of two values, Single- or
MultiUse. It
doesn't refer to Instancing as a property distinct from those two.

And either I'm missing the kick in the head that triggers the AHA or the
article is wrong. It says:

"Depending on whether the server is designed as SingleUse or MultiUse,
another
server process may or may not be launched." It doesn't say which is
which, but
it seems reasonable to assume that "MultiUse" = "another server may be
launched".

It then goes on to say that Excel and Word are SingleUse, which doesn't
seem
right to me. Rather, it seems to have reversed the values.

It does raise an interesting point that reinforces your thoughts, though:
we've been talking about user- and your_code-initiated instances of PPT,
but
there might also be an instance initiated by the user or code activating a
PPT
object (slide or presentation) from within another app.

The fun never ends. ;-)

If it's possible to identify and stop individual processes independent of
the
application instance itself, it sounds as though you're onto a possible
solution to the problem.

Yes, MSFT's terminology can be confusing.
I added to the confusion by initially using the wrong terminology.
MSFT appears to use that terminology consistently in various KB articles.

In effect, it means that for PowerPoint, there is a single instance of the
program running, as you can see if you look at the Task Manager, but there
may be multiple uses of that instance.

For, say Word, you can have multiple instances of Word running, which you
can see in the Task Manager.

After my code works with Powerpoint, if the code has created a NEW instance
of PowerPoint, i.e,, no other PPT had been running, then the code has to
determine whether it is safe to Quit PPT. I only do this, because in the
code of interest, I have no need to leave any Presentation active. For the
latterm the issue is not relevant, I'd just let PPT live!

At some point, I need to examine the running processes to determine whether
anybody else started using PPT AFTER I created the NEW instance.

The logic of the solution is straight-forward.
The only issue is how to do it.

I found a number of examples in the MSFT KB, one at ALLAPI, and one in Steve
Roman's API book that demonstrate how to use EnumProcesses, so I think I
can do this.

One disappointment is that PSAPI.DLL is supported only on NT/2000/XP.
Other mechanisms are available for Win 95/Win 98/Win Me.

Unfortunately, I no longer have a Win 98 system and my ancient Win 95 system
does not have the resources to run a VBA version of PPT. So, I will include
code to detect the OS and prevent the PPT stuff from runniing on other OS,
or warn the user that they cannot run code that starts PPT until AFTER my
PPT code has completed, unless PPT was already running.

I'll be disabling keyboard and mouse input during the interval my code needs
to decide whether to Quit PPT, so the user will not be able to start PPT
from the desktop during the very short interval my code is deciding whether
to Quit PPT.

Yes, I am a masochist!

"Mike M." wrote in message
...
Steve, I think this terminology goes against the grain. Sort of like
Unicast and Multicast in streaming video. MultiUse means that multiple
users attach to the single instance server. SingleUse means each user
gets
their own instance of the server. AHA?

Terminology is in the eye of the beholder, heck, I still think that "PC"
means "plug compatible", not "imPersonal Computer".

In article , Mike M. wrote:
Steve, I think this terminology goes against the grain. Sort of like
Unicast and Multicast in streaming video. MultiUse means that multiple
users attach to the single instance server. SingleUse means each user gets
their own instance of the server. AHA?

AHA!

Only Microsoft ... shakes head ....

Your passion is the software that inspires use to make it imparsible.

After my code works with Powerpoint, if the code has created a NEW instance
of PowerPoint, i.e,, no other PPT had been running, then the code has to
determine whether it is safe to Quit PPT. I only do this, because in the
code of interest, I have no need to leave any Presentation active. For the
latterm the issue is not relevant, I'd just let PPT live!

I'm caught up on that end of things. It was the confusion over multi/single
that set me back a notch or two. g

One other possibility (another KB article says this won't work with PPT97, not
sure of later versions, and that might be a deal-breaker for you, but ...)

If you use CreateObject("PowerPoint.Application") it launches PPT if PPT isn't
already running, gives you a ref to the running copy otherwise.

And if you set the ref to nothing, PowerPoint goes away IF your code launched
it. If it was alive first, it seems to stay alive after. If you invoke PPT
then somebody else does, then you quit, it still stays alive. I've poked at it
a bit this evening and it seems to work. How widely/reliably I can't promise.

The bug on PPT 97 is referenced in one of the links from that same 288902
article.

If that works, it could save lots of APIdiving.

Unfortunately, I no longer have a Win 98 system and my ancient Win 95 system
does not have the resources to run a VBA version of PPT.

If you run into this problem often, a copy of Virtual PC or VMWare is a
wonderful investment. One PC, multiple operating systems.

Yes, I am a masochist!

You've fallen in among people who write code to automate PPT. You fit right
in.

-----------------------------------------
Steve Rindsberg, PPT MVP
PPT FAQ: www.pptfaq.com
PPTools: www.pptools.com
================================================

I also use C++ to automate PowerPoint and initially I was having a problem
with getting PowerPoint to go away after I closed my reference to it. That
was using PPT 2000. I didn't have any trouble (well, that specific trouble)
once I started using PPT 2002. I vaguely remember thinking there was a
problem with the reference counting in that version of PPT but it might just
be a bad sector in my memory or bad programming. I am becoming more
susceptible to both.

"Steve Rindsberg" wrote in message
...
After my code works with Powerpoint, if the code has created a NEW
instance
of PowerPoint, i.e,, no other PPT had been running, then the code has to
determine whether it is safe to Quit PPT. I only do this, because in the
code of interest, I have no need to leave any Presentation active. For
the
latterm the issue is not relevant, I'd just let PPT live!

I'm caught up on that end of things. It was the confusion over
multi/single
that set me back a notch or two. g

One other possibility (another KB article says this won't work with PPT97,
not
sure of later versions, and that might be a deal-breaker for you, but ...)

If you use CreateObject("PowerPoint.Application") it launches PPT if PPT
isn't
already running, gives you a ref to the running copy otherwise.

And if you set the ref to nothing, PowerPoint goes away IF your code
launched
it. If it was alive first, it seems to stay alive after. If you invoke
PPT
then somebody else does, then you quit, it still stays alive. I've poked
at it
a bit this evening and it seems to work. How widely/reliably I can't
promise.

The bug on PPT 97 is referenced in one of the links from that same 288902
article.

If that works, it could save lots of APIdiving.

Unfortunately, I no longer have a Win 98 system and my ancient Win 95
system
does not have the resources to run a VBA version of PPT.

If you run into this problem often, a copy of Virtual PC or VMWare is a
wonderful investment. One PC, multiple operating systems.

Yes, I am a masochist!

You've fallen in among people who write code to automate PPT. You fit
right
in.

-----------------------------------------
Steve Rindsberg, PPT MVP
PPT FAQ: www.pptfaq.com
PPTools: www.pptools.com
================================================