fix problem for offline
fix problem for offline

caosiyang/tcpcopy,sshling/tcpcopy,daodaoliang/tcpcopy,ycaihua/tcpcopy,liviusATnetskope/second,left2right/tcpcopy,daodaoliang/tcpcopy,ycaihua/tcpcopy,eliteYang/tcpcopy,wfxiang08/tcpcopy,u20024804/tcpcopy,liviusATnetskope/second,horryq/tcpcopy,sshling/tcpcopy,left2right/tcpcopy,horryq/tcpcopy,eliteYang/tcpcopy,wfxiang08/tcpcopy,caosiyang/tcpcopy,u20024804/tcpcopy