Diff between package etc contents and current etc contents

etc_deb_diff.sh

#!/bin/bash

# From this stackexchange question: http://unix.stackexchange.com/questions/72746

set -e

package=php5-fpm
mkdir $package
cd $package

# download the package
apt-get download $package

# deb package files are ar archives
ar vx $package*.deb
# containing some compressed tar archives
tar xzf data.tar.gz
# now you have the files

# you can get diffs for all of the files in etc if you would like
find etc -type f |
while read file ; do
    diff $file /$file
done