#!/bin/ksh
# Written By	: Kynan Dent
# Written On	: 20/04/2004
# Function		: Look through files in /etc for anything containing $1 and 
#               replace it with $2.  Note that there is massive scope to screw
#               up with this script - there is little data validation and I 
#               suspect that spaces in the hostname will probably break it.

if [ $# -ne 2 ];then
	echo "Usage: <old name> <new name>"
else
	typeset -lL1 ANSWER
	read ANSWER?"Are you sure you want to do this (y/n)? "
	if [ "$ANSWER" = "y" ];then
		LEN=$((`echo $1 | wc -c`-1))
		if [ $LEN -lt 1 ] ;then
			echo "Invalid hostname."
		else
			TIMESTAMP=`date +%y%m%d-%H%M`
			find /etc -type f -exec /usr/xpg4/bin/grep -q csg905 {} \; -print | grep -v mnttab > filelist.$$
			# make a backup
			echo "Changing hostname from\n$1\nto\n$2" > README
			echo README >> filelist.$$
			tar -cf ./namechange.$TIMESTAMP.backup.tar -I filelist.$$
			rm README
			# go
			cat filelist.$$ | while read afile
			do
				echo "Updating $afile"
				cp $afile $afile.$TIMESTAMP.hostname-change
				sed "s/$1/$2/g" $afile.$TIMESTAMP.hostname-change > $afile
			done
			rm filelist.$$
		fi
	else
		echo "$0 did NOT run at user request."
	fi
fi