diff --git a/distrib/sets/lists/tests/mi b/distrib/sets/lists/tests/mi
index 78b4f2ac3ba9..23d74c090111 100644
--- a/distrib/sets/lists/tests/mi
+++ b/distrib/sets/lists/tests/mi
@@ -1,4 +1,4 @@
-# $NetBSD: mi,v 1.1016 2021/02/07 01:53:54 rillig Exp $
+# $NetBSD: mi,v 1.1017 2021/02/13 06:29:45 rillig Exp $
 #
 # Note: don't delete entries from here - mark them as "obsolete" instead.
 #
@@ -3523,6 +3523,7 @@
 ./usr/tests/lib/libcurses/terminfo.db			tests-obsolete		obsolete
 ./usr/tests/lib/libcurses/tests				tests-lib-tests		compattestfile,atf
 ./usr/tests/lib/libcurses/tests/add_wch			tests-lib-tests		compattestfile,atf
+./usr/tests/lib/libcurses/tests/addbytes		tests-lib-tests		compattestfile,atf
 ./usr/tests/lib/libcurses/tests/addch			tests-lib-tests		compattestfile,atf
 ./usr/tests/lib/libcurses/tests/addchnstr		tests-lib-tests		compattestfile,atf
 ./usr/tests/lib/libcurses/tests/addchstr		tests-lib-tests		compattestfile,atf
diff --git a/tests/lib/libcurses/t_curses.sh b/tests/lib/libcurses/t_curses.sh
index 91dc0e69f6de..8b6ead66e22d 100644
--- a/tests/lib/libcurses/t_curses.sh
+++ b/tests/lib/libcurses/t_curses.sh
@@ -98,6 +98,16 @@ varcheck_body()
 # curses add characters to window routines
 ##########################################
 
+atf_test_case addbytes
+addbytes_head()
+{
+	atf_set "descr" "Tests adding bytes to stdscr"
+}
+addbytes_body()
+{
+	h_run addbytes
+}
+
 atf_test_case addch
 addch_head()
 {
@@ -2172,6 +2182,7 @@ atf_init_test_cases()
 	atf_add_test_case varcheck
 
 	# curses add characters to window routines
+	atf_add_test_case addbytes
 	atf_add_test_case addch
 	atf_add_test_case waddch
 	atf_add_test_case mvaddch
@@ -2416,4 +2427,3 @@ atf_init_test_cases()
 	atf_add_test_case underscore
 	atf_add_test_case wunderscore
 }
-
diff --git a/tests/lib/libcurses/tests/Makefile b/tests/lib/libcurses/tests/Makefile
index 5e923d4c4bce..b3c0cbf0f36c 100644
--- a/tests/lib/libcurses/tests/Makefile
+++ b/tests/lib/libcurses/tests/Makefile
@@ -1,4 +1,4 @@
-# $NetBSD: Makefile,v 1.4 2020/10/24 14:21:26 martin Exp $
+# $NetBSD: Makefile,v 1.5 2021/02/13 06:29:45 rillig Exp $
 
 NOMAN=		# defined
 
@@ -11,6 +11,7 @@ TESTSDIR=	${TESTSBASE}/lib/libcurses
 FILESDIR=	${TESTSDIR}/tests
 FILES=		start
 FILES+=		add_wch
+FILES+=		addbytes
 FILES+=		addch
 FILES+=		addchnstr
 FILES+=		addchstr
diff --git a/tests/lib/libcurses/tests/addbytes b/tests/lib/libcurses/tests/addbytes
new file mode 100644
index 000000000000..a1626f542772
--- /dev/null
+++ b/tests/lib/libcurses/tests/addbytes
@@ -0,0 +1,17 @@
+# $NetBSD: addbytes,v 1.1 2021/02/13 06:29:45 rillig Exp $
+#
+# Tests adding bytes to stdscr.
+
+include start
+
+call OK addbytes "\t" 1
+call2 0 8 getyx STDSCR
+
+call OK addbytes "123456" 6
+call2 0 14 getyx STDSCR
+
+call OK addbytes "\t" 1
+call2 0 16 getyx STDSCR
+
+call OK addbytes "\n" 1
+call2 1 0 getyx STDSCR