}
			nr++
		}
		if nr == maxConsecutiveEmptyReads {
			return n, io.ErrNoProgress
		}
		b.n += m
		n += int64(m)
		if err != nil {
			break
		}
	}
	if err == io.EOF {
		// If we filled the buffer exactly, flush preemptively.
		if b.Available() == 0 {
			err = b.Flush()
		} else {
			err = nil
		}
	}
	return n, err
}

// buffered input and output