Permissions advice needed.

Brett Davidson brett at
Mon Jan 8 19:55:12 UTC 2007

I have a curious problem.

I need an executable file to be owned by a user's uid and gid so they
can run it.
HOWEVER, I don't want them to be able to modify or delete the file
and/or it's permissions. Another program will do that.

This, under standard Unix permissions, is a tad difficult. :-)

ACL's don't help here as the owner of a file has the ability to change

I could set the immutable bit (Linux term for the schg flag) but the
modifying program does not recognise this flag and will thus fail to
modify the file.
(I have no control over the modifying program).

Any ideas?

I don't want to go down the line of using BSD MAC but I'm starting to
think I may have too just to be able to prevent the user from modifying
ONE file! (I'm not even sure I could implement this using MAC anyway).


More information about the freebsd-questions mailing list