diff --git a/cmdline.sh b/cmdline.sh
index ba6eead2..96edec34 100755
--- a/cmdline.sh
+++ b/cmdline.sh
@@ -4,6 +4,9 @@
 # SPDX-License-Identifier: GPL-3.0-or-later
 # shellcheck enable=all
 
+printf '%s\n' "${0-}" || echo $?
+printf '%s\n' "${0-}" | grep -q -m 1 -- 'cmdline.sh$' || echo $?
+
 if test "${A5K_FUNCTIONS_INCLUDED:-false}" = 'false'; then
   main()
   {