diff --git a/include/rt_names.h b/include/rt_names.h
index 37adbd3..56b649a 100644
--- a/include/rt_names.h
+++ b/include/rt_names.h
@@ -8,6 +8,7 @@
 const char *rtnl_rttable_n2a(__u32 id, char *buf, int len);
 const char *rtnl_rtrealm_n2a(int id, char *buf, int len);
 const char *rtnl_dsfield_n2a(int id, char *buf, int len);
+const char *rtnl_group_n2a(int id, char *buf, int len);
 
 int rtnl_rtprot_a2n(__u32 *id, const char *arg);
 int rtnl_rtscope_a2n(__u32 *id, const char *arg);