code: func (s *blockStore) deleteFile(fileNum uint32) error {
  	filePath := blockFilePath(s.basePath, fileNum)
  	if err := os.Remove(filePath); err != nil {
  		return makeDbErr(database.ErrDriverSpecific, err.Error(), err)
  	}
  
  	return nil
  }
docs: // deleteFile removes the block file for the passed flat file number.  The file
  // must already be closed and it is the responsibility of the caller to do any
  // other state cleanup necessary.