线程同步:一:相互排斥同步  1.原子訪问是windows仅仅有的线程同步       InterlockedExchange   改变值       InterlockedIncrement  ++       InterlockedDecrement  --       InterlockedExchangeAdd    +=       实现旋转锁:锁一段代码       void CThreadOurDlg::OnBnClickedButton1()       {        AfxBeginThread(&CThreadOurDlg::ThreadA,this);        AfxBeginThread(&CThreadOurDlg::ThreadB,this);       }       long int g_x=0;       BOOL flag=FALSE;       long int a=100;       long int b=200;       UINT _cdecl CThreadOurDlg::ThreadA(LPVOID lpvoid)       {        while(InterlockedExchange((LONG*)&flag,TRUE)==TRUE)         Sleep(0);        a=a+b;        TRACE("--------------------------------\n");        TRACE("%d\n",a);        TRACE("--------------------------------\n");        InterlockedExchange((LONG*)&flag,FALSE);        return 0;       }        UINT _cdecl CThreadOurDlg::ThreadB(LPVOID lpvoid)        {        while(InterlockedExchange((LONG*)&flag,TRUE)==TRUE)         Sleep(0);        a=a+b;        TRACE("++++++++++++++++++++++++++++++++\n");        TRACE("%d\n",a);        TRACE("++++++++++++++++++++++++++++++++\n");        InterlockedExchange((LONG*)&flag,FALSE);         return 0;        }        旋转锁实现卖票:        long nTicket = 1000;        BOOL nFlag=FALSE;        UINT _cdecl CThreadOurDlg::ThreadFun(LPVOID lpvoid)        {         int i=(int)lpvoid;         while(1)         {          if(nTicket<=0)          {           break;          }          if(nTicket>0)          {           //------------------------------------------------------------枷锁----------------------------------------           while(InterlockedExchange((LONG*)&nFlag,TRUE)==TRUE)              Sleep(0);           CString str;           str.Format(_T("第%d窗体卖出第%d张票"),i,nTicket);           TRACE("第%d窗体卖出第%d张票\n",i,nTicket);           InterlockedDecrement(&nTicket);           //---------------------------------------------------------解锁----------------------------------------------           InterlockedExchange((LONG*)&nFlag,FALSE);          }          Sleep(20);         }         TRACE("第%d窗体没有票了\n",i);         return 0;        }        void CThreadOurDlg::OnBnClickedButton2()        {         //创建10个工作者线程         for(int i=0;i<10;i++)         {          AfxBeginThread(&CThreadOurDlg::ThreadFun,(LPVOID)i);         }        }  2.临界区       2.1 Windows的函数       CRITICAL_SECTION cs;       ::InitializeCriticalSection(&cs);初始化临界区       ::InitializeCriticalSectionAndSpinCount(&cs,4000);包括旋转锁       ::DeleteCriticalSection(&cs);销毁       ::TryEnterCriticalSection尝试进入临界区       ::EnterCriticalSection(&((CThreadOurDlg*)AfxGetApp()->m_pMainWnd)->cs);进入       ::LeaveCriticalSection(&((CThreadOurDlg*)AfxGetApp()->m_pMainWnd)->cs);退出       2.2 MFC的函数       CCriticalSection o_cs;       o_cs.Lock();       o_cs.Unlock();  3.相互排斥量  内核模式  有系统管理      3.1 MFC的类      void CThreadOurDlg::OnBnClickedButton2()       {        //创建10个工作者线程        for(int i=0;i<10;i++)        {         AfxBeginThread(&CThreadOurDlg::ThreadFun,(LPVOID)i);        }        //释放相互排斥量        ::ReleaseMutex(mx.m_hObject);       }       UINT _cdecl CThreadOurDlg::ThreadFun(LPVOID lpvoid)       {        int i=(int)lpvoid;        while(1)        {         if(nTicket<=0)         {          break;         }         //----------------------------------等待相互排斥量信号------------------------------------         ::WaitForSingleObject(((CThreadOurDlg*)AfxGetApp()->m_pMainWnd)->mx.m_hObject,INFINITE);         if(nTicket>0)         {          CString str;          str.Format(_T("第%d窗体卖出第%d张票"),i,nTicket);          TRACE("第%d窗体卖出第%d张票\n",i,nTicket);          ((CThreadOurDlg*)AfxGetApp()->m_pMainWnd)->m_listBox.AddString(str);          InterlockedDecrement(&nTicket);         }         //释放相互排斥量         ::ReleaseMutex(((CThreadOurDlg*)AfxGetApp()->m_pMainWnd)->mx.m_hObject);         Sleep(20);        }        TRACE("第%d窗体没有票了\n",i);        return 0;       }       3.2 HANDLE m_hMutex ;       //创建一个相互排斥量       m_hMutex=CreateMutex(NULL,FALSE,NULL);       CloseHandle(m_hMutex);       m_hMutex=NULL;  4.事件      三个进度条一起跑      4.1MFC类   CEvent cc(FALSE,TRUE);人工      4.2Windows   HANDLE m_hEvent;      ::WaitForSingleObject(m_hEvent,INFINITE);  5.信号量    5.1Windows    HANDLE m_hSingle;             m_hSingle = ::CreateSemaphore(NULL,0/*初始值有几个信号*/,3/*最多能释放几个信号*/,NULL);          ::RealeaseSemaphore(m_hSingle,3/*一次释放多少个*/,NULL/*上一次释放多少个*/);    5.2MFC CSemaphore