vectors = g_newa (GOutputVector, n_vectors);
    map_infos = n_memories ? g_newa (GstMapInfo, n_memories) : NULL;

    for (i = 0, j = 0, k = 0, bytes_to_write = 0; i < n_messages; i++) {
      vectors[j].buffer = messages[i].data_is_data_header ?
          messages[i].data_header : messages[i].data;
      vectors[j].size = messages[i].data_size;
      bytes_to_write += vectors[j].size;
      j++;

      if (messages[i].body_data) {
        vectors[j].buffer = messages[i].body_data;
        vectors[j].size = messages[i].body_data_size;
        bytes_to_write += vectors[j].size;
GST_ERROR ("body_data, preparing to write %d byes", messages[i].body_data_size);
gst_util_dump_mem (messages[i].body_data, messages[i].body_data_size);
        j++;
      } else if (messages[i].body_buffer) {
        gint l, n;

        n = gst_buffer_n_memory (messages[i].body_buffer);
        for (l = 0; l < n; l++) {
          GstMemory *mem = gst_buffer_peek_memory (messages[i].body_buffer, l);

          gst_memory_map (mem, &map_infos[k], GST_MAP_READ);
          vectors[j].buffer = map_infos[k].data;
          vectors[j].size = map_infos[k].size;
GST_ERROR ("body_buffer, preparing to write %d byes", map_infos[k].size);
gst_util_dump_mem (map_infos[k].data, map_infos[k].size);
          bytes_to_write += vectors[j].size;

          k++;
          j++;
        }
      }
    }

GST_ERROR ("writng %d byes", bytes_to_write);
    res =
        writev_bytes (watch->conn->output_stream, vectors, n_vectors,
        &bytes_written, FALSE, watch->conn->cancellable);
    g_assert (bytes_written == bytes_to_write || res != GST_RTSP_OK);