version number and reverified data recording rate

cpp/data_recorder.cpp

@@ -185,6 +185,7 @@ void DataRecorder::write_data() {
 
         // A chunk is ready write it out
         int cnt = write(out_fd, &(data_buffer[buffer_ind]), WRITE_CHUNK_SIZE);
+        total_bytes += cnt;
         if (cnt < 0)
         {
             printf("File write error!\n");