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Boost Thread 和 bind 的使用

CyberC++ — Mon, 07 May 2012 06:10:00 GMT

http://wenku.baidu.com/view/d18b5a0e7cd184254b353599.html?from=rec&pos=0&weight=471&lastweight=46&count=5

from Page 25

CyberC++ 2012-05-07 14:10 发表评论

多线程 Mutex 的运用

CyberC++ — Mon, 23 May 2011 04:46:00 GMT

    HANDLE m_hMutex;

    m_hMutex = CreateMutex(NULL, false, NULL );
    if (!m_hMutex)
    {
        char cBuffer[1024];
        sprintf_s(cBuffer, 1024, "  Unable to create a mutex. Error: %d", GetLastError());
        LOG(2, cBuffer);
    }

    if (m_hMutex)
    {
        CloseHandle(m_hMutex);
    }

    while ((r = WaitForSingleObject(m_hMutex, 5000)) != WAIT_OBJECT_0)
    {
        char cBuffer[1024];
        switch (r)
        {
        case WAIT_TIMEOUT:
            sprintf_s(cBuffer, 1024, "  Backup system account lock failed (timeout). Locked by %s (%d), request from %s (%d)",
                m_sLockFile.c_str(), m_unLockLine,
                sFile.c_str(), unLine);
            LOG(2, cBuffer);
            break;
        case WAIT_ABANDONED:
            sprintf_s(cBuffer, 1024, "  Backup system account lock failed (abandoned). Locked by %s (%d), request from %s (%d)",
                m_sLockFile.c_str(), m_unLockLine,
                sFile.c_str(), unLine);
            LOG(2, cBuffer);
            break;
        case WAIT_FAILED:
            sprintf_s(cBuffer, 1024, "  Backup system account lock failed (failed: %d). Locked by %s (%d), request from %s (%d)",
                GetLastError(),
                m_sLockFile.c_str(), m_unLockLine,
                sFile.c_str(), unLine);
            LOG(2, cBuffer);
            break;
        default:
            sprintf_s(cBuffer, 1024, "  Backup system account lock failed (unknown). Locked by %s (%d), request from %s (%d)",
                m_sLockFile.c_str(), m_unLockLine,
                sFile.c_str(), unLine);
            LOG(2, cBuffer);
            break;
        }
    }

    if (!ReleaseMutex(m_hMutex))
    {
        char cBuffer[1024];
        sprintf_s(cBuffer, 1024, "  Mutex release failed. Error: %d", GetLastError());
        LOG(2, cBuffer);
    }

CyberC++ 2011-05-23 12:46 发表评论

关于类的初始化顺序

CyberC++ — Sun, 17 Apr 2011 12:34:00 GMT

总结归纳一下类的初始化顺序，看下面这个例子

1class E : public A
2{
3
4public:
5    E() : b(1), c(2)
6    {
7        printf("E::E() \n");
8    };
9    ~E() {};
10
11private:
12    B b;
13    C c;
14    D d;
15};

类E的初始化顺序是：
A:A()
B::B(i)
C::C(i)
D::D()
E::E()

另外注意类成员变量的初始化顺序：

1class Test
2{
3public:
4    Test() :
5      i(j), j(3)
6    {
7        printf("i = %d, j = %d \n", i, j);
8
9    };
10    ~Test() {};
11private:
12    int j, i;
13};
14

其中 i 和 j 的值都是有意义的，因为初始化的顺序与定义时的顺序有关，与构造函数的顺序无关，所以 i 和 j 的值都是3.

CyberC++ 2011-04-17 20:34 发表评论