diff --git a/control-notify.c b/control-notify.c
index 90ee4ffa..42c1695b 100644
--- a/control-notify.c
+++ b/control-notify.c
@@ -46,8 +46,12 @@ control_notify_input(struct client *c, struct window_pane *wp,
 	if (winlink_find_by_window(&c->session->windows, wp->window) != NULL) {
 		message = evbuffer_new();
 		evbuffer_add_printf(message, "%%output %u ", wp->id);
-		for (i = 0; i < len; i++)
-			evbuffer_add_printf(message, "%02hhx", buf[i]);
+		for (i = 0; i < len; i++) {
+			if (buf[i] < ' ' || buf[i] == '\\')
+			    evbuffer_add_printf(message, "\\%03o", buf[i]);
+			else
+			    evbuffer_add_printf(message, "%c", buf[i]);
+		}
 		control_write_buffer(c, message);
 		evbuffer_free(message);
 	}
diff --git a/tmux.1 b/tmux.1
index 519bf6fa..a669fe9c 100644
--- a/tmux.1
+++ b/tmux.1
@@ -3672,7 +3672,7 @@ The new layout is
 .It Ic %output Ar pane-id Ar value
 A window pane produced output.
 .Ar value
-contains that output with each byte encoded as two hex digits.
+escapes non-printable characters and backslash as octal \\xxx.
 .It Ic %session-changed Ar session-id Ar name
 The client is now attached to the session with ID
 .Ar session-id ,