code: private void writeIndex(int entryAddress,
                            byte []entryBuffer, int offset, int length)
    {
      long address = _segment.getAddress() + entryAddress;
  
      if (_segment.length() < entryAddress + length) {
        throw new IllegalStateException(L.l("offset=0x{0} length={1}", entryAddress, length));
      }
      //try (StoreWrite os = _readWrite.openWrite(address, BLOCK_SIZE)) {
      _sOut.write(address, entryBuffer, offset, length);
      
      _isDirty = true;
      // }
    }
docs: Write the current header to the output.