code: func deserializeWriteRow(writeRow []byte) (uint32, uint32, error) {
  	// Ensure the checksum matches.  The checksum is at the end.
  	gotChecksum := crc32.Checksum(writeRow[:8], castagnoli)
  	wantChecksumBytes := writeRow[8:12]
  	wantChecksum := byteOrder.Uint32(wantChecksumBytes)
  	if gotChecksum != wantChecksum {
  		str := fmt.Sprintf("metadata for write cursor does not match "+
  			"the expected checksum - got %d, want %d", gotChecksum,
  			wantChecksum)
  		return 0, 0, makeDbErr(database.ErrCorruption, str, nil)
  	}
  
  	fileNum := byteOrder.Uint32(writeRow[0:4])
  	fileOffset := byteOrder.Uint32(writeRow[4:8])
  	return fileNum, fileOffset, nil
  }
docs: // deserializeWriteRow deserializes the write cursor location stored in the
  // metadata.  Returns ErrCorruption if the checksum of the entry doesn't match.