intros.
unfold mkdir_oSC in |- *.
elim (fSSC (subjectSC s) u); elim (fsecmat (secmat s) (MyDir p)).
intros; unfold fOSC in |- *; apply AddEq.
intro; apply H.
rewrite H0; simpl in |- *; auto.
auto.
auto.
auto.
Qed.

Lemma EqfOSC3 :
forall (s : SFSstate) (o1 o2 : OBJECT),
o1 <> o2 -> fOSC (objectSC s) o2 = fOSC (unlink_oSC s o1) o2.