diff -wpruN --no-dereference '--exclude=*.orig' a~/fad-getad.c a/fad-getad.c
--- a~/fad-getad.c	1970-01-01 00:00:00
+++ a/fad-getad.c	1970-01-01 00:00:00
@@ -67,7 +67,7 @@
 # ifdef __Lynx__
 /* LynxOS */
 #  include <netpacket/if_packet.h>
-# else /* __Lynx__ */
+# elif defined(linux)
 /* Linux */
 #  include <linux/types.h>
 #  include <linux/if_packet.h>