This question it's a little complicated to make. It's more a curiosity than a technical situation. First I will try to put the situation. Let's say I'm the root of a system, and one of my users (user foo) have his home dir with rwx privileges ( /home/foo/ have permissions 700 ) and I wan't to create a "black box" dir inside it's home, so I cd to /home/foo and do:
# mkdir blackdir # chmod 000 blackdir At this point (as I know) the foo user isn't able to see the content of blackdir, but if the dir is empty he can delete it (rm -df blackdir) cause he have rwx on /home/foo. Someway, user foo can have information about the contents of blackdir: if it's empty he can 'rm -d' it, so he will know if the dir had or not any file. In my way of think, thats "information" about the dir. What is the design cause of this behaviour? I mean, It wouldn't be more logical the fact that if a dir have 000 permissions, the foo user shouldn't be able to get any kind of information about the dir? even something so trivial as if the dir was empty or not. I would like to understand this abstraction point of view of this issue from developers and long-time unix users as you. Thanks for reading. -Jesus
