Compare nsISupprts

jml <[email protected]> Wed, 08 Jan 2003 17:37:48 +0800
Newsgroups gmane.comp.mozilla.devel.xpcom
Organization Another Netscape Collabra Server User
Message-ID <[email protected]>
Hi,
How can I tell whether two xpcom pointer are of same object?

I know that in MS COM one can queryInterface the two pointer to 
IUnknown, then compare the two IUnknow. Is it same is xpcom, that first 
queryInterface to nsISupports then compare the two nsISupports?

Thanks.

jml