code: func NewMuxer(t Type, w io.Writer) *Muxer {
  	max := MaxPackedSize64k
  	if t == Sideband {
  		max = MaxPackedSize
  	}
  
  	return &Muxer{
  		max: max - chLen,
  		e:   pktline.NewEncoder(w),
  	}
  }
docs: // NewMuxer returns a new Muxer for the given t that writes on w.
  //
  // If t is equal to `Sideband` the max pack size is set to MaxPackedSize, in any
  // other value is given, max pack is set to MaxPackedSize64k, that is the
  // maximum length of a line in pktline format.