FILE=/tmp/replace-`date +%s` OLD_STRING=/usr/old-files/bin NEW_STRING=/usr/bin if [ $# -ne 1 ]; then echo neo exit 1 fi if [ `grep "$OLD_STRING" "$1"` ]; then echo "$1" cat "$1" | sed "s,$OLD_STRING,$NEW_STRING,g" > "$FILE" mv "$FILE" "$1" fi