This one requires some analysis!  Cool!

ACL's turns out to be the best answer.  getacl/setacl for AIX, and
getfacl/setfacl for Solaris.

George


James Durham wrote:
> 
> What about this. You create a directory with the permissions. This was only
> the 5 Users can enter the directory.
> 
> drwxr-x---   2 mainact    5users        4096 Mar 22 23:28 Directory/
> 
> The the file will have the permissions.
> 
> -rwxrwxr--   1 mainact    4users       39025 May 26 11:44 Special_file.txt
> 
> This way the people in group 5users and enter the directory and use the
> "OTHER" permissions to read the file. The four that need write can also be
> entered into group 4users which have the group permissions to write.
> 
> Now the "OTHER" permission on the file may be deciving, but no prying eyes
> will be able to read it without being able to execute the directory. The only
> people who can execute the directory is the 5users.
> 
> On Tuesday 23 July 2002 05:41 am, 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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