code: public static void formatFileHeader(String fileName, Transaction tx) {
  		tx.concurrencyMgr().modifyFile(fileName);
  		// header should be the first block of the given file
  		if (VanillaDb.fileMgr().size(fileName) == 0) {
  			FileHeaderFormatter fhf = new FileHeaderFormatter();
  			Buffer buff = tx.bufferMgr().pinNew(fileName, fhf);
  			tx.bufferMgr().unpin(buff);
  		}
  	}
docs: Format the header of specified file.
  
  @param fileName
  the file name
  @param tx
  the transaction