Add timestamp to the begining of dmesg output

watch-dmesg.bash

#!/bin/bash
#
# watch-dmesg.bash
#
# Add timestamp to the begining of dmesg output
# This is only usefull when dmesg does not support "-T" parameter
#
# Crontab Entry
# * * * * * /bin/bash /home/centos/bin/watch-dmesg.bash

BASE_NAME=watch-dmesg

cd /home/centos/bin

dmesg > $BASE_NAME.prev

if [ ! -f $BASE_NAME.prev ]; then
	touch $BASE_NAME.prev
fi

if [ ! -f $BASE_NAME.text ]; then
	touch $BASE_NAME.text
fi

LINE_END_COUNT=$( wc -l $BASE_NAME.prev | awk '{print $1}' )
LINE_BEGIN_COUNT=$( wc -l $BASE_NAME.text | awk '{print $1}' )

tail -n $(( $LINE_END_COUNT - $LINE_BEGIN_COUNT )) $BASE_NAME.prev | \
	 awk '{ print strftime(), $0; fflush() }' \
	 >> $BASE_NAME.text