禁止重复运行

HANDLE hMutex;  //全局

hMutex = CreateMutex(NULL,FALSE,_T("ArwenApp"));

 if(GetLastError() == ERROR_ALREADY_EXISTS){ //如果已经存在同名的Mutex会得到这个错误
     CloseHandle(hMutex);
	MessageBox(NULL, TEXT("禁止重复运行"), TEXT("警告:"), MB_ICONWARNING);
     return FALSE;
  }
   CloseHandle(hMutex);// 退出时候关闭句柄