code: func (s *Scanner) SeekObjectHeader(offset int64) (*ObjectHeader, error) {
  	// if seeking we assume that you are not interested in the header
  	if s.version == 0 {
  		s.version = VersionSupported
  	}
  
  	if _, err := s.r.Seek(offset, io.SeekStart); err != nil {
  		return nil, err
  	}
  
  	h, err := s.nextObjectHeader()
  	if err != nil {
  		return nil, err
  	}
  
  	h.Offset = offset
  	return h, nil
  }
docs: // SeekObjectHeader seeks to specified offset and returns the ObjectHeader
  // for the next object in the reader