#!/bin/csh# Script: renames a file -- C/TC shellsif ( $#argv < 2 ) then        # Argument checking	echo "Usage: $0 file1 file2 " 	exit 1endifif ( -e $1 ) then             # Check for file existence	mv $1 $2                  # Rename file1	echo $1 has been renamed to $2else	echo "$1 doesn't exist"	exit 2endif