diff --git a/sys/include_list.h b/sys/include_list.h
new file mode 100644
index 0000000..ad86f24
--- /dev/null
+++ b/sys/include_list.h
@@ -0,0 +1,9 @@
+#ifndef LPC_INCLUDE_LIST_H
+#define LPC_INCLUDE_LIST_H
+
+/* Return value flag types for include_list() */
+
+#define INCLIST_FLAT         0x00
+#define INCLIST_TREE         0x01
+
+#endif /* LPC_INCLUDE_LIST_H */