docs: public void updateEntry(final Entry entry, String fsid) throws Exception {
          synchronized (FileStore.getFileStore()) {
  
              final Feed f = getFeedDocument();
  
              if (fsid.endsWith(".media-link")) {
                  fsid = fsid.substring(0, fsid.length() - ".media-link".length());
              }
  
              updateTimestamps(entry);
  
              updateEntryAppLinks(entry, fsid, false);
              updateFeedDocumentWithExistingEntry(f, entry);
  
              final String entryPath = getEntryPath(fsid);
              final OutputStream os = FileStore.getFileStore().getFileOutputStream(entryPath);
              updateEntryAppLinks(entry, fsid, true);
              Atom10Generator.serializeEntry(entry, new OutputStreamWriter(os, "UTF-8"));
              os.flush();
              os.close();
          }
      }