Re: Another SetTimer question

From:
"Scott McPhillips [MVP]" <org-dot-mvps-at-scottmcp>
Newsgroups:
microsoft.public.vc.mfc
Date:
Sun, 29 Jul 2007 11:35:48 -0400
Message-ID:
<0bOdnR2m5apFLjHbnZ2dnUVZ_o6knZ2d@comcast.com>
learnyourabc wrote:

I use the WaitForSingleObject(eventobj,timedelay) for the time delay
to replace the sleep function. There will be a event object that will
be signalled if the user exits the program.Is this right? see below.

HANDLE ExitEventObj;

UINT WorkerThreadProc( LPVOID Param )
{
//wait for 10 secs unless user press exit button then return and
proceed immediately
     if (WaitForSingleObject(ghGlobalWriteEvent, 10000) !=
WAIT_OBJECT_0)
    {
        printf("delay for 10 secs - WaitForSingleObject failed (%d)
\n", GetLastError());
    }
    else
    {
        printf("Timer was signaled or exit button is pressed.\n");
    }

//do some stuff

   return TRUE;
}
void CTestDoc::OnTestStartwaittimer()
{

ExitEventObj = CreateEvent(
        NULL, // default security attributes
        TRUE, // manual-reset event
        TRUE, // initial state is signaled
        TEXT("ExitEvent") // object name
        );

    if (ExitEventObj == NULL)
    {
        printf("CreateEvent failed (%d)\n", GetLastError());
        return;
    }

if (! ResetEvent(ExitEventObj) )
    {
        printf("ResetEvent failed (%d)\n", GetLastError());
        return;
    }

    m_WinThread =
AfxBeginThread(WorkerThreadProc,this,THREAD_PRIORITY_NORMAL,0,0,NULL);

    MessageBox(NULL,"Thread Started",NULL,MB_OK);

}

void CTestDoc::OnTestStopwaittimer()
{
//signal the event object
if (! SetEvent(ghGlobalWriteEvent) )
    {
        printf("SetEvent failed (%d)\n", GetLastError());
    }
}


This approach will do what you want: suspend the thread until timeout OR
the event is set. You have some details wrong: ghGlobalWriteEvent
should be the same variable as ExitEventObj. The TEXT parameter in
CreateEvent is not needed (you can pass NULL).

--
Scott McPhillips [MVP VC++]

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