diff --git a/cmd.c b/cmd.c
index 8f69ed92..02d2ac41 100644
--- a/cmd.c
+++ b/cmd.c
@@ -636,7 +636,7 @@ cmd_list_free(struct cmd_list *cmdlist)
 
 /* Copy a command list, expanding %s in arguments. */
 struct cmd_list *
-cmd_list_copy(struct cmd_list *cmdlist, int argc, char **argv)
+cmd_list_copy(const struct cmd_list *cmdlist, int argc, char **argv)
 {
 	struct cmd	*cmd;
 	struct cmd_list	*new_cmdlist;
@@ -667,7 +667,7 @@ cmd_list_copy(struct cmd_list *cmdlist, int argc, char **argv)
 
 /* Get a command list as a string. */
 char *
-cmd_list_print(struct cmd_list *cmdlist, int escaped)
+cmd_list_print(const struct cmd_list *cmdlist, int escaped)
 {
 	struct cmd	*cmd, *next;
 	char		*buf, *this;
diff --git a/tmux.h b/tmux.h
index bde95365..996bbfbf 100644
--- a/tmux.h
+++ b/tmux.h
@@ -2680,12 +2680,12 @@ struct cmd	*cmd_copy(struct cmd *, int, char **);
 void		 cmd_free(struct cmd *);
 char		*cmd_print(struct cmd *);
 struct cmd_list	*cmd_list_new(void);
-struct cmd_list	*cmd_list_copy(struct cmd_list *, int, char **);
+struct cmd_list	*cmd_list_copy(const struct cmd_list *, int, char **);
 void		 cmd_list_append(struct cmd_list *, struct cmd *);
 void		 cmd_list_append_all(struct cmd_list *, struct cmd_list *);
 void		 cmd_list_move(struct cmd_list *, struct cmd_list *);
 void		 cmd_list_free(struct cmd_list *);
-char		*cmd_list_print(struct cmd_list *, int);
+char		*cmd_list_print(const struct cmd_list *, int);
 struct cmd	*cmd_list_first(struct cmd_list *);
 struct cmd	*cmd_list_next(struct cmd *);
 int		 cmd_list_all_have(struct cmd_list *, int);