clean add_preamble_license

		if (grep -q "Copyright (C)" $f); then

			echo "License-preamble is already present in $f"

			echo "No license-preamble is added."

			cat $f > $f.oldlic

			awk '/^\/\*/{c++} c!=1; /^ \*\//{c++}' "$f" > $f

			echo "Done!"

			echo "Mo license-preamble is added."

		else

			echo "Adding license-preamble to $f ..."

			cat $LICENSE_PREAMBLE $f > $f.new

			cat $f > $f.nolic

			cat $LICENSE_PREAMBLE "$f" > "$f.new"

			mv $f.new $f

			rm $f.new

			echo "Done!"

		fi

		echo " "