--- a/src/dcwsocket.c.linux
+++ b/src/dcwsocket.c.linux
@@ -36,6 +36,9 @@
 #include <linux/filter.h>
 #include <arpa/inet.h>
 
+#ifndef SO_ATTACH_FILTER
+#define SO_ATTACH_FILTER  26
+#endif
 
 #define ETHER_HEADERSIZE  14
 #define CL3_HEADERSIZE    4
