send email if new entry is made to kern.log

.sh

#!/bin/bash

# http://serverfault.com/questions/24428/monitoring-dmesg-output

MAILTO=root
LOG=/var/log/kern.log

OFFSET_FILE=$0.offset


if [ ! -f $OFFSET_FILE ]; then echo 0 > $OFFSET_FILE; fi
OFFSET=`cat $OFFSET_FILE`
FILESIZE=`cat $LOG|wc -c`

# Check if log has been rotated
if [ "$OFFSET" -gt "$FILESIZE" ]; then
  OFFSET=0
  echo 0 > $OFFSET_FILE
fi
if [ "$FILESIZE" -gt "$OFFSET" ]; then
  tail -c+$OFFSET $LOG|sed "s/^/  /"|mail $MAILTO -s "new kernel alerts"
  echo $FILESIZE > $OFFSET_FILE
fi