rv = spec->GetPersistentDescriptorString(string);
rv = spec->GetNativePath(string);
nsresult GetStringFromSpec(nsFileSpec inSpec, char **string){	nsresult rv;	nsCOMPtr<nsIFileSpec> spec;	rv = NS_NewFileSpecWithSpec(inSpec, getter_AddRefs(spec));	if (NS_SUCCEEDED(rv)) {        	rv = spec->GetPersistentDescriptorString(string);		if (NS_SUCCEEDED(rv)) {			return NS_OK;                }		else {			PR_FREEIF(*string);			return rv;		}        } 	else {		*string = nsnull;		return rv;	}}