克服让人纠结的CLOSE_WAIT就靠它了

linger m_sLinger;
m_sLinger.l_onoff=1;// (在closesocket()调用,但是还有数据没发送完毕的时候容许逗留)
m_sLinger.l_linger = 0; // (容许逗留的时间为0秒)
setsockopt(cmdsocket,SOL_SOCKET,SO_LINGER,(const char*)&m_sLinger,sizeof(linger));
closesocket(cmdsocket);