errrm, why not just `func Copy(dst Writer, src Reader) (written int64, err error)` ? avoid having to select/poll and just let the io.Reader and io.Writer inter

errrm, why not just `func Copy(dst Writer, src Reader) (written int64, err error)` ? avoid having to select/poll and just let the io.Reader and io.Writer interfaces do the work for you... and if they implemenet WriteTo, all the better.