HowTo: Use Win32 critical-section calls?

I'm having problems getting the Win32 CriticalSection calls to work. In the following code, the call to EnterCriticalSection seems to be ignored, and each call to SearchFunc gets the value 'z', rather than the first getting 'A', the second getting 'a', and the third getting 'z'.

Am I doing something wrong, or leaving something out?

I was expecting that the matched pairs of EnterCriticalSection and LeaveCriticalSection would prevent the main thread from running past the _beginthreadex calls until each thread had a chance to get started. The threads should run for 5 seconds, with interspersed A's and a's and z's. Instead, all three threads seem to be created as if called with 'z'. Also, I'm not certain that three threads are created.

// EeTestMultiThread.cpp
#include "stdafx.h"
#include <process.h>

CRITICAL_SECTION gCriticalSection;
volatile DWORD   gTickCountStop;
#define  PROXY_LIMIT  50000000

UINT __stdcall SearchFunc(void* pArguments)
{
  UINT* pArgs = (UINT*)pArguments;
  UINT  curTransIndex = *pArgs;
  UINT  proxyFoundCount = 0;
  ::printf("Reached SearchFunc: %d\n", curTransIndex);
  ::LeaveCriticalSection(&gCriticalSection);
 
  while (TRUE) {
    UINT  curTickCount = ::GetTickCount();
    if (curTickCount > gTickCountStop) {
      break;
    }
    proxyFoundCount += curTransIndex;
    if (proxyFoundCount > PROXY_LIMIT) {
      printf("%c", curTransIndex);
      proxyFoundCount = 0;
    }
  }
  printf("Search: %d\n", proxyFoundCount);
  ::_endthreadex(0);
  return 0;
}

int main(void)
{
  ::InitializeCriticalSection(&gCriticalSection);
  gTickCountStop = (::GetTickCount() + 5000); // Run for 5 seconds
  UINT   threadID;
  HANDLE hThread[3];
  UINT   transIndex = 'A';
  ::EnterCriticalSection(&gCriticalSection);
  hThread[0] = (HANDLE)::_beginthreadex(NULL, 0, &SearchFunc,
                                        &transIndex, 0, &threadID);

  transIndex = 'a';
  ::EnterCriticalSection(&gCriticalSection);
  hThread[1] = (HANDLE)::_beginthreadex(NULL, 0, &SearchFunc,
                                        &transIndex, 0, &threadID);

  transIndex = 'z';
  ::EnterCriticalSection(&gCriticalSection);
  hThread[2] = (HANDLE)::_beginthreadex(NULL, 0, &SearchFunc,
                                        &transIndex, 0, &threadID);

  ::WaitForMultipleObjects(3, hThread, TRUE, INFINITE);
  ::DeleteCriticalSection(&gCriticalSection);
  return 0;
}


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