Question

I have a task that requires me to delete all folders in a directory that aren’t symlinked, keeping only the symlinked folders and the symlinks.

If I have for instance 3 resources: link, linked_folder and unlinked folder. link and linked_folder will be kept.

Currently I have managed to get this code, which works for the file naming structure we have, but I’d like to know if there is a cleaner solution?

protected_folders=`ls -l | awk '/^l/ {printf $10}' | tr '/' '|'`;
symlinks=`ls -l | awk '/^l/ {print $8}' | tr "\n" "|"`;
protected_resources=$protected_folders$symlinks;
protected_resources=${protected_resources:0:${#protected_resources}-1};
folders_to_delete=`ls | grep -v -E "$protected_resources"`; 
echo $folders_to_delete | tr '\n' ' ' | tr ' ' '\000' | xargs -0 rm -rf

I know the above command can be done on one line, but I’ve separated it as I’ve been requested to have it more “readable”.

Any help would be appreciated.

Answer 1

It might be easier to move the symlinks and their targets to a new directory, then replace the old directory with the new.

WARNING: this is just a rough sketch, to give you the idea. [UPDATE: clean up and make it less like pseudo-code]

# Make an empty directory to hold the symlinks and targets
# that you want to keep
DIR_TO_CLEAN=/the/directory/to/clean/up
TMP_DIR=$(mktemp -d)

for x in $DIR_TO_CLEAN/*; do
    # Move each symlink and its target to the new directory
    [[ -h $x ]] && mv $x $(readlink -f $x) $TMP_DIR
done

# FIRST!!!, confirm that $TMP_DIR has everything you want to keep,
# and $DIR_TO_CLEAN has nothing you want to keep
rm -rf $DIR_TO_CLEAN
mv $TMP_DIR $DIR_TO_CLEAN