func readShortUtf8(rd *bufio.Reader) ([]byte, int) {
	size := rd.ReadB()
	b := rd.ReadCesu8(int(size))
	return b, int(size)
}
func readShortUtf8(rd *bufio.Reader) ([]byte, int) {
	size := rd.ReadB()
	b := rd.ReadCesu8(int(size))
	return b, int(size)
}
// strings with one byte length