Unix Permissions

Total of 9 users: 5 read only, 4 read/write.

George



Jay wrote:
>
> Hmmm...this is a good one. Not 100% sure (I don't have time right now to
> test all the possibilities), but how about:
>
> * The file in question is called "file" and it is located in "directory"
>
> * There are users 1, 2, 3, 4, and 5.
>
> * Users 1-4 are in the "read" and "write" groups and user 5 is only in the
> "read" group
>
> With the above scenario, this might work:
>
> chown root:write /directory/
> chown root:read /directory/file
> chmod 0750 /directory/file
> chmod 2751 /directory/
>
> The SGID bit on /directory/ should allow users in the "write" group to
> override it's unwritable permissions. I think... :)
>
> ???
>
> ~Jay
>
> On Tue, 23 Jul 2002, George Toft wrote:
>
> > I was given this puzzle, and told it cannot be solved using Unix:
> >
> > You have a file that needs protected from prying eyes. You must allow
> > only 5 people read access, and 4 people read/write access. The rest of
> > the world cannot be allowed to view it. What set of Unix permissions
> > and ownership can support this?
> >
> > George
> > ________________________________________________
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> >
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>
> --
> ~Jay
>
> ________________________________________________
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>
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