#!/bin/sh
#
# /usr/local/bin/myip
#
# This script displays the machine's current IP address
# as well as options to save it in a log file and show the
# last (old) IP log entry.

if=eth0		# interface to check (change this if it's wrong)

iplog=/var/log/myip.log

usage()
	{
	echo "$0:  print my IP address for a link"
	echo "USAGE: $0 [-p][-l]" >&2
	echo "where:	-p  show previous address" >&2
	echo "		-l  print IP address log" >&2
	echo "		-w  write the new IP address to the log" >&2
	}

case "$1" in
	-p)	tail -1 $iplog | awk '{print $NF}' ;;
	-l)	cat $iplog ;;
	-w)	echo `date` `$0` >>$iplog ;;
	-?|-h)	usage ;;
	*)	/sbin/ifconfig $if | awk '/inet addr:/ { ip=substr($2,6); print ip }' ;;
esac