static void ffm_set_write_index(AVFormatContext *s, int64_t pos,
                                int64_t file_size)
{
    av_opt_set_int(s, "server_attached", 1, AV_OPT_SEARCH_CHILDREN);
    av_opt_set_int(s, "ffm_write_index", pos, AV_OPT_SEARCH_CHILDREN);
    av_opt_set_int(s, "ffm_file_size", file_size, AV_OPT_SEARCH_CHILDREN);
}
static void ffm_set_write_index(AVFormatContext *s, int64_t pos,
                                int64_t file_size)
{
    av_opt_set_int(s, "server_attached", 1, AV_OPT_SEARCH_CHILDREN);
    av_opt_set_int(s, "ffm_write_index", pos, AV_OPT_SEARCH_CHILDREN);
    av_opt_set_int(s, "ffm_file_size", file_size, AV_OPT_SEARCH_CHILDREN);
}