C++使用临界区来控制多线程访问同一个变量

#include

#include

using namespace std;

int index = 0;

// 临界区结构对象
CRITICAL_SECTION g_cs;

HANDLE hMutex = NULL;

void changeMe()
{
 cout << index++ << endl;
}

void changeMe2()
{
 cout << index++ << endl;
}
void changeMe3()
{
 cout << index++ << endl;
}

DWORD WINAPI th1(LPVOID lpParameter)
{
 while(1)
 {
  Sleep(1600); //sleep 1.6 s
  // 进入临界区
  EnterCriticalSection(&g_cs);

  // 等待互斥对象通知
  //WaitForSingleObject(hMutex, INFINITE);

  // 对共享资源进行写入操作
  //cout << "a" << index++ << endl;
  changeMe();
  changeMe2();
  changeMe3();

  // 释放互斥对象
  //ReleaseMutex(hMutex);

  // 离开临界区
  LeaveCriticalSection(&g_cs);  
 }
 return 0;
}

DWORD WINAPI th2(LPVOID lpParameter)
{
 while(1)
 {
  
  Sleep(2000); //sleep 2 s
  // 进入临界区
  EnterCriticalSection(&g_cs);

  // 等待互斥对象通知
  //WaitForSingleObject(hMutex, INFINITE);

  //cout << "b" << index++ << endl;
  changeMe();
  changeMe2();
  changeMe3();

  // 释放互斥对象
  //ReleaseMutex(hMutex);

  // 离开临界区
  LeaveCriticalSection(&g_cs); 
 }
 return 0;
}

int main(int argc, char* argv[])
{
 // 创建互斥对象
 //hMutex = CreateMutex(NULL, TRUE, NULL);
 // 初始化临界区
 InitializeCriticalSection(&g_cs);

 HANDLE hThread1;
 HANDLE hThread2;
 hThread1 = CreateThread(NULL, 0, th1,  NULL, 0, NULL);
 hThread2 = CreateThread(NULL, 0, th2,  NULL, 0, NULL);
 int k;
 cin >> k;
 printf("Hello World!\n");
 return 0;
}