code:

#!/sbin/sh
# 
# /system/addon.d/91-cm.sh
# During a CM10 upgrade, this script backs up /system/etc/hosts,
# /system is formatted and reinstalled, then the file is restored.
#

. /tmp/backuptool.functions

list_files() {
cat <<EOF
app/com.nolanlawson.logcat.apk
lib/libplus_jni_v8.so
lib/librs.antblur_constant.so
lib/librs.antblur_drama.so
lib/librs.antblur.so
lib/librs.drama.so
lib/librs.film_base.so
lib/fixedframe.so
lib/grey.so
lib/image_wrapper.so
lib/retrolux.so
lib/librsjni.so
lib/libRSSupport.so
lib/libwebp_android.so
app/com.google.android.apps.plus.apk
EOF
}

case "$1" in
  backup)
    list_files | while read FILE DUMMY; do
      backup_file $S/"$FILE"
    done
  ;;
  restore)
    list_files | while read FILE REPLACEMENT; do
      R=""
      [ -n "$REPLACEMENT" ] && R="$S/$REPLACEMENT"
      [ -f "$C/$S/$FILE" ] && restore_file $S/"$FILE" "$R"
    done
	rm /system/app/Calendar.apk
	rm /system/app/CMFileManager.apk
	rm /system/app/CMFileManagerThemes.apk
	rm /system/app/CMWallpapers.apk
	rm /system/app/Email2.apk
	rm /system/app/Exchange2.apk
	rm /system/app/Galaxy4.apk
	rm /system/app/HoloSpiralWallpaper.apk
	rm /system/app/LiveWallpapers.apk
	rm /system/app/MagicSmokeWallpapers.apk
	rm /system/app/NoiseField.apk
	rm /system/app/PhaseBeam.apk
	rm /system/app/QuickSearchBox.apk
	rm /system/app/Trebuchet.apk
	rm /system/app/VideoEditor.apk
	rm /system/app/VisualizationWallpapers.apk
  ;;
  pre-backup)
    # Stub
  ;;
  post-backup)
    # Stub
  ;;
  pre-restore)
    # Stub
  ;;
  post-restore)
    # Stub
  ;;
esac