code: func readBlockAt(reader io.ReadSeeker, offset int64) (fileBlock, error) {
  	var block fileBlock
  	_, err := reader.Seek(offset, os.SEEK_SET)
  	if err != nil {
  		return block, err
  	}
  	return block, binary.Read(reader, binary.LittleEndian, &block)
  }
docs: // Read meta-info at specified place