code: func (b *ByteBuf) ReadInt() (int, error) {
  	if b.Readable() < 4 {
  		return 0, io.ErrShortBuffer
  	}
  
  	b.readerIndex += 4
  	return Byte2Int(b.buf[b.readerIndex-4 : b.readerIndex]), nil
  }
docs: // ReadInt get int value from buf