If there are files or folders the current user should be denied access to, should their sizes be displayed when the user asks, for example with the
ls -l command on Linux or the places the Windows Explorer shell puts this information? Alternatively, should the OS show the size without the denied file(s)/folder(s)?
I can see the merits of both sides of this argument. In some cases, the user should be denied access to any information on these files & folders, and that includes their sizes. However, if a user, who is not an administrator at the moment but wants to see how much space is left to install programs etc. (more on Windows than Linux, as Linux has a better permissions system in my opinion), he/she may want to know this. Also, many times the OS denies access to "files that are important to the running of the computer and should never be touched even by super-ultra-mega-users", but if these files get too big, the user may wish to know. Usually there are tools to find this out, and I suppose there is always some way to find out/fix it, but there are always those edge cases.
I am looking at whether the parent/ancestor folder's true size should be shown, because I understand there are times where the denied files/folders shouldn't be shown at all, much less their sizes. I also acknowledge that there are different sizes the OS can show, such as "size on disk" or "apparent size", so you don't have to go into this.
So should the OS deny access to information about the sizes of these files? Should there be a special permission just for sizes of files, or is there already? How do OS's usually deal with this?