static int flac_write_trailer(struct AVFormatContext *s) { ByteIOContext *pb = s->pb; uint8_t *streaminfo = s->streams[0]->codec->extradata; int len = s->streams[0]->codec->extradata_size; int64_t file_size; if (streaminfo && len > 0 && !url_is_streamed(s->pb)) { file_size = url_ftell(pb); url_fseek(pb, 8, SEEK_SET); put_buffer(pb, streaminfo, len); url_fseek(pb, file_size, SEEK_SET); put_flush_packet(pb); } return 0; }