[ls flag] schg [chflags flag] schg, schange, simmutable [Owner-settable] No [OS support] All [Semantics and rationale] File cannot be changed, renamed, moved, or removed [Attribute] 
System immutable
A r c h i v e d
O p a q u e
N o d u m p
S y s t e m a p p e n d - o n l y
S y s t e m i m m u t a b l e
U s e r a p p e n d - o n l y
U s e r i m m u t a b l e
H i d d e n