diff --git a/lib/if.h b/lib/if.h
index 9ffe74c..c6469ea 100644
--- a/lib/if.h
+++ b/lib/if.h
@@ -181,7 +181,7 @@
 
 /* Prototypes. */
 struct interface *if_new (void);
-struct interface *if_create (void);
+struct interface *if_create (char *name, int namelen);
 struct interface *if_lookup_by_index (unsigned int);
 struct interface *if_lookup_by_name (char *);
 struct interface *if_lookup_exact_address (struct in_addr);