"mv" command wrapper to change file name using "sed".

name_sedder.sh

#!/bin/bash
#$Id: name_sedder.sh,v 1.1 2012-10-13 09:13:03+09 shirai Exp $

before="$1"
after="$2"
old_name=$3

main(){
  check_args $@
	new_name="`echo $old_name | sed "s/$before/$after/g" `"
	mv -vi $old_name $new_name
}

check_args(){
if [[ "$before" == "" || "$after" == "" || ! -e $old_name ]];then
	echo " PLEASE INPUT TWO WORDS AND FILE NAME" >&2
	echo "Usage: $0 present_name new_name file_name" >&2
	exit 1
fi
}

main $@