通用套接字选项

高性能服务器涉及到的套接字选项：

http://www.cppblog.com/killsound/archive/2009/01/16/72138.html

http://blog.youkuaiyun.com/fullsail/article/details/4424324

http://www.blogjava.net/killme2008/archive/2008/06/23/209961.html

环境：windows

网络模式: iocp

套接字选项: SO_SNDBUF, 关闭发送缓冲区,避免一次内存拷贝
        nZero = 0;
        nRet = setsockopt(m_sdListen, SOL_SOCKET, SO_SNDBUF, (char *)&nZero, sizeof(nZero));
        if( nRet == SOCKET_ERROR )
       

套接字选项: so_SO_SNDBUF

        //关闭连接的时候，发送缓冲区和接受缓冲区中的所有数据都丢弃，但是会有tim_wait错误
        LINGER lingerStruct;
        lingerStruct.l_onoff = 1;
        lingerStruct.l_linger = 0;

        nRet = setsockopt(m_sdListen, SOL_SOCKET, SO_LINGER,
        (char *)&lingerStruct, sizeof(lingerStruct) );
        if( nRet == SOCKET_ERROR )