This script will send an email when a file changes in the given path. Can’t remember where I picked this up from but it’s useful to have when you need to debug something that writes files.

#!/bin/sh
#
# Monitor file $1 for changes
# Send an alert emai to $2 if file $1 changes
# usage: file_change_mail_alert.sh /var/log/messages your.name@domain.com
#
if [ -z “$2” ]; then

echo "Usage: file_change_mail_alert.sh "

exit 1

fi
#if a inotifywait for this file is already running

if [ $(ps aux | grep inotifywait | grep -c “$1” ) -gt ‘0’ ]; then

echo “A process monitoring the file $1 is already running: $(ps aux | grep inotifywait | grep “$1” )”;

exit 1;

fi
#if inotifywait exists

type -P inotifywait &>/dev/null || { echo "Error: This script requires inotifywait(http://wiki.github.com/rvoicilas/inotify-tools/) … apt-get install inotify-tools … " >&2; exit 1; }
#if the file exists
if [ -f $1 ]; then
echo “Monitoring file $1 for changes - sending alerts to $2”
while inotifywait -e modify -e attrib -e move -e delete $1 -o /root/audit.log; do

sleep 1
# changes="$(tail -n5 $1)"

changes="$(cat /root/audit.log)"
	echo "The following change occurred in the file $1 : $changes" | mail -s "Change in $1" $2
	rm /root/audit.log
	touch /root/audit.log		
done

else

echo “Error: File $1 not found”

fi