#!/bin/bash

# Author:    Francis David Donato Pereira (knancys)
#      e-mail des-fdavid@netsite.com.br
#      InstantMessagers   ICQ # 174253802   / MSN knancys@hotmail.com / YAHOO fdavid_knancys

# Usage:    checkURL.sh <URL>
# Version:    1.1

# Change log
# 2005 Aug 16 -   Published first version
# 2005 Aug 25 - (bug) Don't update the file source to compare, after the first comparison

# Temporary files
export file_source=/tmp/source.checkURL
export file_target=/tmp/target.checkURL

rm $file_target -f
rm $file_source -f

# Variables
export msg="Update URL's file"
export inter=60

# Save URL Source in file to compare
wget -q $1 -O $file_source


while true; do
  # Save URL Target in file to compare
  wget -q $1 -O $file_target
  
  # Test and if to find returns 1 in case that I oppose to return 0
  export result_test=$((diff $file_source $file_target -qa) | grep differ -c)
  
  # Print date
  if test $result_test = 1; then
     echo $(date) $msg;
     wget -q $1 -O $file_source
  fi
  
  # Waiting n seconds
  sleep $inter
done;