[FFmpeg-devel] Which library are compiled when using gcc -lavformat, in /usr/local/lib or /usr/lib/

[forumhelp forum]

Hello,

I'm using Ubuntu LTS 10.04

I hae installed ffmpeg through two different steps:
-using the apt-get install command (libavformat-dev libav-format-extra-52 ffmpeg libavcodec-dev libx264-dev ...)
-following a HOWTO tutorial to build ffmpeg with libx264
http://ubuntuforums.org/showthread.php?t=786095

so now I have the include folder (libavformat libavcodec ...) in two places
-/usr/include
-/usr/local/include
and libraries are in
-/usr/lib
-/usr/local/lib
I also installed gcc and g++ using apt-get install build-essential

I have written a program to parse media using the command to compile
gcc -Wall -g test_AV_Coder.c -o AV_coder -lavformat -lavcodec -lavutil -lbz2 -lm -lz -lfaac -lmp3lame -lx264 -lfaad -lpthread
But I don't know which libraries and header files are incuded?

I try to parse an mp3  file, and I have a segmentaion fault when I access:
AVFormatContext->streams[i]->codec
Anyone has an idea why is that happening?

also is there a way to have the most recent documentation offline, beside having (libav-doc)
because i don't have the following in my documentation in avcodec structure
AVCodecDefault* defaults

thanks in advance
Zouhair