uhd

    //setup defaults for unspecified values

    args.otw_format = args.otw_format.empty()? "sc16" : args.otw_format;

    args.channels = args.channels.empty()? std::vector<size_t>(1, 0) : args.channels;

    //calculate packet size

    static const size_t hdr_size = 0

            if (chan < num_chan_so_far){

                const size_t dsp = num_chan_so_far - chan - 1;

                _mbc[mb].rx_dsps[dsp]->set_nsamps_per_packet(spp); //seems to be a good place to set this

                my_streamer->set_xport_chan_get_buff(chan_i, boost::bind(

                    &zero_copy_if::get_recv_buff, _mbc[mb].rx_dsp_xports[dsp], _1

                ));