Question

I know it’s been asked but what I’ve found has not worked out so far.
The closet I came is this : rename -n 'y[A-Z]/[a-z]/' *
which works for the current directory. I’m not too good at Linux terminal so what
should I add to this command to apply it to all of the files in all the sub-directories from which I am in, thanks!

Answer 1

Here’s one way using find and tr:

for i in $(find . -type f -name "*[A-Z]*"); do mv "$i" "$(echo $i | tr A-Z a-z)"; done

Edit; added: -name "*[A-Z]*"

This ensures that only files with capital letters are found. For example, if files with only lowercase letters are found and moved to the same file, mv will display the are the same file error.