#!/bin/sh
# Copyright (c) 2006 Mihail Fedorov, http://mihailfedorov.ru
# $ ./whois.sh domain.tld whois.server.tld [email protected]

# change this
WORKDIR="/home/kolo/whoistory"
# thanks

NEWFILE="$WORKDIR/$1.$2"
OLDFILE="$WORKDIR/$1.$2.old"

mv $NEWFILE $OLDFILE 2> /dev/null
whois -h $2 $1 > $NEWFILE 2> /dev/null

oldsize=$(ls -l "$OLDFILE" 2> /dev/null | awk '{print $5}')
newsize=$(ls -l "$NEWFILE" | awk '{print $5}')

if [ "$oldsize" != "$newsize" ]; then
	cat $NEWFILE | mail -s "[Whoistory] $1 updated!" $3
fi

Simple whois monitor for running via crontab and monitoring changes of single (per cron task) domain changes. Compare sizes to exclude unimportant updates

Whois monitor (single domain)

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