I believe that a RIDs are just a subset of SIDs and so you can find them via: 

use Win32;
my( $domain, $sid, $type );
foreach my $id (  "Administrator", "Administrators",
        "Domain Admins"  ) {
    if(  ! Win32::LookupAccountName(
            "", $id, $domain, $sid, $type )  ) {
        warn "Can't lookup SID ($id): $^E\n";
    } else {
        print "$id is of type $type and belongs to $domain.\n";
    }
}
__END__
Administrator is of type 1 and belongs to MY-COMPUTER.
Administrators is of type 4 and belongs to BUILTIN.
Domain Admins is of type 2 and belongs to MYDOMAIN.

[download]

Update: Oh, you probably want a nice string version of the RID... I'll try to look up how to do that tomorrow unless someone beats me to it (please). (:

        - tye (but my friends call me "Tye")

In reply to (tye)Re: Acquiring NT Group RID's by tye
in thread Acquiring NT Group RID's by enoch

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