char* 
ofl_structs_meter_stats_to_string(struct ofl_meter_stats* s){
    char *str;
    size_t str_size;
    FILE *stream = open_memstream(&str, &str_size);
    ofl_structs_meter_stats_print(stream, s);
    fclose(stream);
    return str;
}
static void
ofl_msg_print_stats_reply_meter(struct ofl_msg_multipart_reply_meter *msg, FILE *stream) {
    size_t i;

    fprintf(stream, ", stats=[");

    for (i=0; i<msg->stats_num; i++) {
        ofl_structs_meter_stats_print(stream, msg->stats[i]);
        if (i < msg->stats_num - 1) { fprintf(stream, ", "); };
    }

    fprintf(stream, "]");
}