Haven’t needed to mess with iCacls in the past. Needed to use it today though but the command line help doesn’t quite explain everything.. In particular I didn’t know what (OI) (CI) and (IO) meant.
Answer:
On a different note, I can’t believe I didn’t know it was possible to query the registry from the command line! Head to your nearest Windows command line and run Reg.exe query /? for more information (or just reg.exe /? for adding/removing/etc).