while(1) {
        ($rready,$wready) = IO::Select->select($sel, $sel, undef);
        foreach my $rsocket (@$rready) { 
            if($rsocket == $lsn) {
                new_socket($rsocket);
            }else{
                # whatever
            }
        }
        foreach my $wsocket (@$wready) { 
            gen_chars($wsocket);
        }
    }