macOS: remove all empty directories

For some odd reason my Calibre backup to cloud storage had a bunch of empty directories. I’ve been meaning to remove them, but it’s cumbersome to do so from the web client.

Instead, let’s do it from a local client.

Upon installing the cloud storage software, a local directory is exposed under /Users/$USER/Library/CloudStorage (macOS).

My first instinct is to use find(1):

$ find -empty -type d -delete

However that does not work on macOS:

find: illegal option -- e
usage: find [-H | -L | -P] [-EXdsx] [-f path] path ... [expression]
       find [-H | -L | -P] [-EXdsx] -f path [path ...] [expression]

My second go to choice is fd(1):

$ fd -t e -x rmdir

…this lists all empty directories and invokes rmdir on each of them.