Worker thread calling a global function?

MFC / VC60 / Win9x,Win2k, WinXP

I use AfxBeginThread ( (AFX_THREADPROC) ::MyWorkerThread, this ); to call a worker thread global function UINT MyWorkerThread(LPVOID pParam).  Inside my global function MyWorkerThread() if I call other global functions, say MyFunctionCalledFromInsideMyThread(), do I have to worry about another thread calling this function at the sametime?  Or is the fuction data dublicated for each time MyFunctionCalledFromInsideMyThread() is called inside a different MyTWorkerThread()?
SurferAsked:
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jkrConnect With a Mentor Commented:
>>if I call other global functions, say MyFunctionCalledFromInsideMyThread(), do I have to worry about another
>>thread calling this function at the sametime?

Only if any function you call from within the thread uses global variables. If not, there is nothing to worry about, since each thread has its own stack to store non-global data.

However, if you *have* global variables, it'd be best to not access them directly, but via accessor/manipulator functions that can ensure synchronization, e.g.

int GetGlobalInt () {

    EnterCriticalSection ( &g_csLock);

    int n = g_nGlobalInt;

    LeaveCriticalSection ( &g_csLock);

    return n;
}

void SetGlobalInt ( int n) {

    EnterCriticalSection ( &g_csLock);

    g_nGlobalInt = n;

    LeaveCriticalSection ( &g_csLock);
}
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chensuConnect With a Mentor Commented:
You need synchronization for global and static data but not data on the stack.
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SurferAuthor Commented:
chensu good job on the correct answer but jkr answer really made me understand the concept.  Thanks guys!!



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