-#define _PW_KEYBYNAME '1'
-#define _PW_KEYBYNUM '2'
-#define _PW_KEYBYUID '3'
+#define _PW_KEYBYNAME '1' /* stored by name */
+#define _PW_KEYBYNUM '2' /* stored by entry in the "file" */
+#define _PW_KEYBYUID '3' /* stored by uid */
+
+#define _PASSWORD_EFMT1 '_' /* extended encryption format */