Ubuntu – the command to remove all files but not directories

Try this command:

find . -empty -type d -delete

The find command is used to search for files/directories matching a particular search criteria from the specified path, in this case the current directory (hence the .).

The -empty option holds true for any file and directory that is empty.

The -type d option holds true for the file type specified; in this case d stands for the file type directory.

The -delete option is the action to perform, and holds true for all files found in the search.

First turn on recursive globbing

shopt -s globstar

Now we can look in all directories with **. To unset, you can use shopt -u globstar (it's off by default, so it will be off when you open a new shell).

In all of the below, remove echo after testing to actually create the directories.

If the end-of-tree directories are empty, you could test for emptiness and make the directory only if it is detected... something like

for d in **/; do [[ -z "$(ls -Aq "$d")" ]] && echo mkdir "$d"Texture; done

i.e. if the output of ls -A (hidden files except current and parent dir) -q (printing ? for non-printing characters) is empty, make a directory.

But since the directories contain files, we'd better test that there are no directories

for d in **/; do [[ -z "$(find "$d" -maxdepth 1 -mindepth 1 -type d)" ]] && echo mkdir "$d"Texture; done

mindepth -1 is to stop the current directory being found... find sees hidden files, so we know those are included. Since any character should pass the test (we only want to check the output is empty), this should be fairly safe...

A more concise way (sorry Greg) (but actually all these methods do something similarly iffy - we can just about get away with using filenames as text since we aren't actually trying to do anything with those files themselves here):

for d in **/; do (ls -Alq "$d" | grep -q '^d') || echo mkdir "$d"Textures; done

here we add the -l flag for long output, which prints every file in the form

drwxrwxr-x 5 zanna zanna 4096 Sep 27 22:00 Dir1

we then gulp pipe that stuff into grep to see if any of the lines starts with d (meaning there's a directory). We don't want grep to print any of that meaningless unreliable text, so we just check its exit status with -q to see if it found anything. If it didn't, we make a directory (using the || or operator, meaning, do the next command if the last one failed). This should work, actually, even if your filenames contain horrible characters such as newlines, since ls prints them as ? - every line should start with a letter indicating the file type, so, probably, no kittens will die.