#!/usr/bin/sh

for a in "$@"
do
  base="$(basename "$a")"
  dir="$(dirname "$a")"
  a="$dir/$base"
  b="$dir/$(echo "$base" | tr "[:upper:]" "[:lower:]")"
  if ! test "$a" = "$b"
  then
    echo "$a -> $b"
    mv "$a" "$b"
  fi
done