av_opt_child_class_next  211 fftools/cmdutils.c     while (child = av_opt_child_class_next(class, child))
av_opt_child_class_next 1683 libavutil/opt.c             while (child = av_opt_child_class_next(c, child))
av_opt_child_class_next  655 libavutil/opt.h const AVClass *av_opt_child_class_next(const AVClass *parent, const AVClass *prev);