code: File getSyncLogTemporaryFile(long segmentTxId, long endTxId, long stamp) {
      String name = NNStorage.getFinalizedEditsFileName(segmentTxId, endTxId) +
          ".tmp=" + stamp; 
      return new File(sd.getCurrentDir(), name);
    }
docs: Get name for temporary file used for log syncing, after a journal node
  crashed.