A little something slightly outside my bash scripting skills; I want to make a script which deletes everything in one path not present in another path. It must be fully recursive, so it applies to all files / folders / subfolders inside the two paths. For example, if I have:

/foo1/bar1.txt
/foo2/bar1.txt
/foo2/bar2.txt

The command would delete /foo2/bar2.txt because the file isn't also present in /foo1, but keep /foo2/bar1.txt because it is. Does anyone know of a shell script that takes both base folders as arguments and does this?

Is the data in /foo2/ a copy of the date in /foo1/? If so, you can use rsync with the "delete from target" option. This will sync /foo1 content over to /foo2 and remove any content that is not found in /foo2/ that exists in /foo1.

If the data in the two directories is different, you can write a script to run a find command on /foo2/ and check if the the file or directory exists in /foo1, if not, you can delete it from /foo2.