How to determine if a SID is group or user?

[Tim Potter]

Gerald Carter writes:

> > How would I figure out if a specific ACE entry pertains to 
> > a group or a user?
> > 
> > I can go in and look at the uid and/or gid with sid_to_uid 
> > or sid_to_gid (from the ace), but there must be some 
> > way to differentiate between the group and user ace's.
> 
> Samba uses the last bit as a flag.  Of course, this
> is entirely different from NT.  No idea how to do it 
> on Win32. See passdb/passdb.c:pdb_rid_is_user() for details.

I think the only way to do it in NT is to call the lookup sid
function and check the returned name type value.  This should say
whether the sid is a domain, domain group, domain alias or user
sid.


Tim.