Recursively rename files (change extension) in Linux

I have started to put together a tool to provide a simplified interface to common actions.

You can recursively rename files with glob pattern matching and regex matching like this:

$ npm install @mountbuild/mouse -g
$ mouse rename file -p "tmp/**/*.jpg" -i ".jpg" -o ".png"

If nothing else check out the source and see how to write your own script to do this in JavaScript.

If you have zsh shell, this is satisfaction:

rename -n -e 'EXPRESSION_HERE' **/*

Remove -n to work.

find -execdir rename

https://superuser.com/a/213146/128124 works directly only for suffixes, but this will work for arbitrary regex replacements on basenames:

PATH=/usr/bin find . -depth -execdir rename 's/_dbg.txt$/_.txt' '{}' ;

or to affect files only:

PATH=/usr/bin find . -type f -execdir rename 's/_dbg.txt$/_.txt' '{}' ;

-execdir first cds into the directory before executing only on the basename.

Tested on Ubuntu 20.04, find 4.7.0, rename 1.10.

Convenient and safer helper for it

find-rename-regex() (
  set -eu
  find_and_replace="$1"
  PATH="$(echo "$PATH" | sed -E 's/(^|:)[^/][^:]*//g')" 
    find . -depth -execdir rename "${2:--n}" "s/${find_and_replace}" '{}' ;
)

GitHub upstream.

Sample usage to replace spaces ' ' with hyphens '-'.

Dry run that shows what would be renamed to what without actually doing it:

find-rename-regex ' /-/g'

Do the replace:

find-rename-regex ' /-/g' -v

Command explanation

The awesome -execdir option does a cd into the directory before executing the rename command, unlike -exec.

-depth ensure that the renaming happens first on children, and then on parents, to prevent potential problems with missing parent directories.

-execdir is required because rename does not play well with non-basename input paths, e.g. the following fails:

rename 's/findme/replaceme/g' acc/acc

The PATH hacking is required because -execdir has one very annoying drawback: find is extremely opinionated and refuses to do anything with -execdir if you have any relative paths in your PATH environment variable, e.g. ./node_modules/.bin, failing with:

find: The relative path ‘./node_modules/.bin’ is included in the PATH environment variable, which is insecure in combination with the -execdir action of find. Please remove that entry from $PATH

See also: https://askubuntu.com/questions/621132/why-using-the-execdir-action-is-insecure-for-directory-which-is-in-the-path/1109378#1109378

-execdir is a GNU find extension to POSIX. rename is Perl based and comes from the rename package.

Rename lookahead workaround

If your input paths don't come from find, or if you've had enough of the relative path annoyance, we can use some Perl lookahead to safely rename directories as in:

git ls-files | sort -r | xargs rename 's/findme(?!.*/)/?$/replaceme/g' '{}'

I haven't found a convenient analogue for -execdir with xargs: Xargs: change working directory to file path before executing?

The sort -r is required to ensure that files come after their respective directories, since longer paths come after shorter ones with the same prefix.

Tested in Ubuntu 18.10.

I found this method is easier and easier to read:

find . -name "*.andnav" | rename "s/.andnav$/.tile/"

At least on Ubuntu derivations rename takes a list of files from STDIN if none are on the command line. And this can be tested easily with:

find . -name "*.andnav" | rename -vn "s/.andnav$/.tile/"

until you get it right.

With zsh:

autoload zmv
zmv -n '(**/)(*).andnav' '$1$2.tile'

Remove the -n to actually perform the renaming.

Figured it out

find . -name "*.andnav" -exec rename -v 's/.andnav$/.tile/i' {} ;
./0/0.png.andnav renamed as ./0/0.png.tile
./0/1.png.andnav renamed as ./0/1.png.tile
./1/0.png.andnav renamed as ./1/0.png.tile
./1/1.png.andnav renamed as ./1/1.png.tile

of course remove the -v when actually doing it, or it will waste time displaying all the files

Something like:

find . -name '*.andnav' -exec sh -c 'mv "$0" "${0%.andnav}.tile"' {} ;

Explanation

The above starts walking the directory tree starting at the current working directory (.). Every time a file name matches the pattern *.andnav (e.g., foo.andnav) the following command is executed:

sh -c 'mv "$0" "${0%.andnav}.tile"' foo.andnav

Where $0 is foo.andnav and ${0%.andnav}.tile replaces the .andnav suffix with .tile so basically:

mv foo.andnav foo.tile