diff --git a/includes/osdep.h b/includes/osdep.h
index 89a29d67..866e0f71 100644
--- a/includes/osdep.h
+++ b/includes/osdep.h
@@ -227,6 +227,10 @@
 # define BPF_FORMAT "/dev/bpf%d"
 #endif
 
+#if defined (F_SETFD) && !defined (HAVE_SETFD)
+# define HAVE_SETFD
+#endif
+
 #if defined (IFF_POINTOPOINT) && !defined (HAVE_IFF_POINTOPOINT)
 # define HAVE_IFF_POINTOPOINT
 #endif
@@ -279,4 +283,9 @@
 # define HAVE_AF_LINK
 #endif
 
+/* Linux needs to define SHUT_* in /usr/include/sys/socket.h someday... */
+#if !defined (SHUT_RD)
+# define SHUT_RD 0
+#endif
+
 #endif /* __ISC_DHCP_OSDEP_H__ */