//println!(" mode 2 pkt {}/{} tail {}/{} seq {}", packet_num, num_pkts, tail_size, frame_size, seq_no);
self.slice_buf.resize(tail_size as usize, 0);
self.src.read_buf(self.slice_buf.as_mut_slice())?;
//println!(" mode 2 pkt {}/{} tail {}/{} seq {}", packet_num, num_pkts, tail_size, frame_size, seq_no);
self.slice_buf.resize(tail_size as usize, 0);
self.src.read_buf(self.slice_buf.as_mut_slice())?;