Some style nits.

format.c

@@ -2597,7 +2597,7 @@ format_cb_user(__unused struct format_tree *ft)
 
 	if ((pw = getpwuid(getuid())) != NULL)
 		return (xstrdup(pw->pw_name));
-	return NULL;
+	return (NULL);
 }
 
 /* Format table type. */

screen.c

@@ -661,9 +661,9 @@ screen_mode_to_string(int mode)
 	static char	tmp[1024];
 
 	if (mode == 0)
-		return "NONE";
+		return ("NONE");
 	if (mode == ALL_MODES)
-		return "ALL";
+		return ("ALL");
 
 	*tmp = '\0';
 	if (mode & MODE_CURSOR)

server-acl.c

@@ -42,8 +42,8 @@ static int
 server_acl_cmp(struct server_acl_user *user1, struct server_acl_user *user2)
 {
 	if (user1->uid < user2->uid)
-		return -1;
-	return user1->uid > user2->uid;
+		return (-1);
+	return (user1->uid > user2->uid);
 }
 
 RB_HEAD(server_acl_entries, server_acl_user) server_acl_entries;
@@ -66,7 +66,7 @@ server_acl_user_find(uid_t uid)
 {
 	struct server_acl_user	find = { .uid = uid };
 
-	return RB_FIND(server_acl_entries, &server_acl_entries, &find);
+	return (RB_FIND(server_acl_entries, &server_acl_entries, &find));
 }
 
 /* Display the tree. */

server-client.c

@@ -3158,7 +3158,7 @@ server_client_add_client_window(struct client *c, u_int id)
 		cw->window = id;
 		RB_INSERT(client_windows, &c->windows, cw);
 	}
-	return cw;
+	return (cw);
 }
 
 /* Get client active pane. */

tmux.c

@@ -325,7 +325,7 @@ find_home(void)
 const char *
 getversion(void)
 {
-	return TMUX_VERSION;
+	return (TMUX_VERSION);
 }
 
 int

window-buffer.c

@@ -308,7 +308,7 @@ window_buffer_get_key(void *modedata, void *itemdata, u_int line)
 	}
 	pb = paste_get_name(item->name);
 	if (pb == NULL)
-		return KEYC_NONE;
+		return (KEYC_NONE);
 
 	ft = format_create(NULL, NULL, FORMAT_NONE, 0);
 	format_defaults(ft, NULL, NULL, 0, NULL);
@@ -320,7 +320,7 @@ window_buffer_get_key(void *modedata, void *itemdata, u_int line)
 	key = key_string_lookup_string(expanded);
 	free(expanded);
 	format_free(ft);
-	return key;
+	return (key);
 }
 
 static struct screen *

window-client.c

@@ -281,7 +281,7 @@ window_client_get_key(void *modedata, void *itemdata, u_int line)
 	key = key_string_lookup_string(expanded);
 	free(expanded);
 	format_free(ft);
-	return key;
+	return (key);
 }
 
 static struct screen *

window-tree.c

@@ -895,7 +895,7 @@ window_tree_get_key(void *modedata, void *itemdata, u_int line)
 	key = key_string_lookup_string(expanded);
 	free(expanded);
 	format_free(ft);
-	return key;
+	return (key);
 }
 
 static struct screen *