Reset copyright year of each source file in Git

reset-copyright-year.sh

#!/bin/bash

dir=$1
old=$2

files=$(ack -l "Copyright $old")

for f in $files; do
	year=$(git log --follow -M -C --format=%ad --date=format:%Y $f | tail -1)
	echo "$year : $f"
	rpl -q "Copyright $old" "Copyright $year" $f
done

rpl does not add any trailing newline, but is an extra command to install. Alternatively use perl -i -pe "s#${2}#${3}#g"