diff --git a/ripd/rip_routemap.c b/ripd/rip_routemap.c
index 45a45f4..ffe1317 100644
--- a/ripd/rip_routemap.c
+++ b/ripd/rip_routemap.c
@@ -47,7 +47,7 @@
 /* Add rip route map rule. */
 int
 rip_route_match_add (struct vty *vty, struct route_map_index *index,
-		     char *command, char *arg)
+		     const char *command, char *arg)
 {
   int ret;
 
@@ -70,7 +70,7 @@
 /* Delete rip route map rule. */
 int
 rip_route_match_delete (struct vty *vty, struct route_map_index *index,
-			char *command, char *arg)
+			const char *command, char *arg)
 {
   int ret;
 
@@ -93,7 +93,7 @@
 /* Add rip route map rule. */
 int
 rip_route_set_add (struct vty *vty, struct route_map_index *index,
-		   char *command, char *arg)
+		   const char *command, char *arg)
 {
   int ret;
 
@@ -116,7 +116,7 @@
 /* Delete rip route map rule. */
 int
 rip_route_set_delete (struct vty *vty, struct route_map_index *index,
-		      char *command, char *arg)
+		      const char *command, char *arg)
 {
   int ret;