Re: Killing thread from outside thread in MFC App

From:
"Tom Serface" <tom.nospam@camaswood.com>
Newsgroups:
microsoft.public.vc.mfc
Date:
Sat, 14 Apr 2007 07:21:22 -0700
Message-ID:
<FBB3270B-6D14-41FE-87B1-C9766F610A0A@microsoft.com>
Also, Rob, if you plan to set the value of running outside of the loop that
is checking it, assuming that's how you exit the thread loop, you may want
to make it a volatile variable to force the optimizer to check it each time.

Tom

"Rob" <millerman@ozemail.com.au> wrote in message
news:46205f13$0$13135$5a62ac22@per-qv1-newsreader-01.iinet.net.au...

Sorry, here's an extract of my code:

//Declaration:

static UINT MyThreadProc(LPVOID p);
void MyThreadProc();
volatile BOOL running;

// begin thread when user presses Go
void CSmartTimerDlg::OnGo()
{
   .
   .
   .
   running = TRUE;
   AfxBeginThread(MyThreadProc, this);
}

UINT CSmartTimerDlg::MyThreadProc(LPVOID p)
{
    CSmartTimerDlg * me = (CSmartTimerDlg *)p;
    me->MyThreadProc();
    return 0;
}

void CSmartTimerDlg::MyThreadProc()
{
    processing code here
}

//When user presses clear button to cancel on dialog box, end thread
void CSmartTimerDlg::OnClear()
{
    running = FALSE;
}

"Joseph M. Newcomer" <newcomer@flounder.com> wrote in message
news:t7j0231los01ru48681skt8bv4ockp12tt@4ax.com...

See below...
On Sat, 14 Apr 2007 10:43:30 +1000, "Rob" <millerman@ozemail.com.au>
wrote:

Hi,

Thanks to all those who offered advise on my last query. I successfully
used
the worker thread method to give control back to the dialog box whilst
background processing was being carried out.

The issue I have now is closing that thread externally. The method I've
used
to create the thread uses a volatile boolean variable. Whilever it is set
to
TRUE, the thread remains alive. However, when I set the variable to FALSE
from the calling process (user wants to end processing), it has no
effect.
The thread continues to run.

****
This is one of the most common paradigms for shutting down a thread. So
it should work;
show your code.
joe
****

I thought that declaring the variable as 'volatile' would allow for the
thread to be closed externally. What else do I need to do to?

Thanks,
Rob


Joseph M. Newcomer [MVP]
email: newcomer@flounder.com
Web: http://www.flounder.com
MVP Tips: http://www.flounder.com/mvp_tips.htm

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