情况是这样的:fd_set创建并初始化:fd_setreadset;//fd_setnamedreadsetFD_ZERO(&readset);//clearingfd_setFD_SET(listen_socket,&readset);//addingalisteningsockettoreadset/*usefortimeout*/timevalblocktime;blocktime.tv_sec=0;blocktime.tv_usec=0;现在，当前值显示listen_socket已添加到readset:readset.fd_count=1readset.fd_array[0]=