message: Future check in append mode
diff: @@ -296,6 +296,10 @@ void BP4Writer::InitBPBuffer()
  if (m_BP4Serializer.m_Aggregator.m_IsConsumer)
  {
  + if (m_FutureOpenFiles.valid())
  + {
  + m_FutureOpenFiles.get();
  + }
  m_BP4Serializer.m_PreDataFileLength =
  m_FileDataManager.GetFileSize(0);
  