#!/bin/sh
set -e

#do the files exists?
if [ ! -f "$1.new" ]; then exit 0; fi

#do the original file exists?
if [ ! -f "$1" ]
then 
  mv $1.new $1
  exit 0
fi

#they do, compare them, but ignore the line with 
if diff -I "Last modified:.*" $1.new $1 > /dev/null
then #they are the same - choose the old one, but set actual timestamp
  rm -f $1.new
  touch $1
else #they differ
  mv -f $1.new $1
fi