code: func ChangeProp32(xu *xgbutil.XUtil, win xproto.Window, prop string, typ string,
  	data ...uint) error {
  
  	buf := make([]byte, len(data)*4)
  	for i, datum := range data {
  		xgb.Put32(buf[(i*4):], uint32(datum))
  	}
  
  	return ChangeProp(xu, win, 32, prop, typ, buf)
  }
docs: // ChangeProperty32 makes changing 32 bit formatted properties easier
  // by constructing the raw X data for you.