Global Common Update Retardation 1

[coldneut]

After several days of complete frustration over why my code
wasn't working I finally realized the problem.

I am using some global common variables to exchange data among
different classes. When I enter a new class module (such as a
dialog) I pick up the global variable current values OK. I make a
change to them, then look at them and they are indeed changed
locally. However they are not changed in other class modules
until I exit the dialog. When I re-enter the dialog, I get the
latest global values which are the response to my original intent.
One target of my global variables is a classless thread which
should be in memory executing at all times.

Does anyone out there know a "work around" so global variables
are changed for all modules when changed locally?

 

[Cagliostro]

Can you give a short sample? As far as I understand you have problems with thread's syncronisation. I think you need there critical sections. They are designed just for syncronisations of threads. John Fill

ivfmd@mail.md

 

[coldneut]

John:

Thanks for your response. What I am doing is creating a thread with a subroutine
at the top of a program so as not to be a part of a class. I am using
AfxBeginThread(comCode, (LPVOID) ThreadIdx).

The thread (comcode) works something like this:

int A, B;

UINT comCode(LPVOID ThreadIdx) {

A = 0; B = 0;

while(true) {
if(A == 1) B++;
}

In a piece of dialog code I have as an event handler:

extern int A, B;
MyDilog::test {
char s[20];
A = 1;
sprintf(s,"A = %d, B = %d",A,B);
AfxMessageBox(s);
}

No matter how mant times I press the button to bring up
this event, I see A =1, B=0;

If I exit the whole dialog, and then bring it back up again, lo and
behold A=1 and B has incremented.

I hope this helps. I'm perplexed.

Joe

 

[Cagliostro]

If A is 1 B starts to increment. You will not be able to predict there the value of B, because you are not able to predict how much time A will be 1. John Fill

ivfmd@mail.md

 

[coldneut]

John:

The problem is that B remains 0 while A is 1 as I go in and
out of the event that sets A to 1. B only changes if I completely
exit the dialog and then come back in.

Joe

 

[Cagliostro]

If you open dialog from the thread, this thread stops while dialog is active. It means, runnging of thread switch into dialog's WndProc. John Fill

ivfmd@mail.md

 

[coldneut]

The dialog is not opened from the thread. The thread is run outside
of any class so as not to be hampered by anything else.

 

[Cagliostro]

OnWichMessage() do you set A to 1? John Fill

ivfmd@mail.md

 

[coldneut]

I don't understand your question. I am settind A=1 in one
of the dialog's event handlers. Afterward I view the result
using AfxMessageBox.

 

[Cagliostro]

Try like following. Maybe it'll help.
extern int A, B;
MyDilog::test {
char s[20];
::A = 1;
John Fill

ivfmd@mail.md

 

[coldneut]

I tried the ::A=1 and there was no difference.

I am thinking along the lines of the thread being suspended
while the dialog is executing. I tried to add
SetThreadExecutionState(ES_SYSTEM_REQUIRED | ES_CONTINUOUS)
to the thread and got an error starting program:
"linked to missing export KERNEL32.DLL:SetThreadExecutionState"
(I am using Windows 95) . It scares me to death to think of replacing the
KERNEL32.DLL if I can find a more recent one.

Do you think this is worth pursuing?

 

[Cagliostro]

Maybe, but I don't believe that. John Fill

ivfmd@mail.md

 

[Cagliostro]

By the way, how many processors do you have on your computer and what kind of processors? John Fill

ivfmd@mail.md

 

[coldneut]

John:

My computer has one Pentium II. The problem seems to
have corrected itself. I've changed so many things that I
am at a loss as to what fixed it. I think I will let well
enough alone and hope it doesn't reappear. Thanks for
all your help.