give the position offset of the file in the packet

update seek regression test reference file accordingly
patch by Daniel Cardenas: Daniel Car cox net
original thread: [Ffmpeg-devel] [PATCH] Debug help for file position
date: 05/01/2007 02:42 AM

Originally committed as revision 8871 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/utils.c

@@ -729,6 +729,7 @@ static int av_read_frame_internal(AVFormatContext *s, AVPacket *pkt)
                 /* return packet if any */
                 if (pkt->size) {
                 got_packet:
+                    pkt->pos = s->cur_pkt.pos;              // Isn't quite accurate but close.
                     pkt->duration = 0;
                     pkt->stream_index = st->index;
                     pkt->pts = st->parser->pts;