diff --git a/tests/maxlen.bash b/tests/maxlen.bash
new file mode 100755
index 0000000..f009df2
--- /dev/null
+++ b/tests/maxlen.bash
@@ -0,0 +1,18 @@
+#!/bin/bash -eu
+#
+# Find out the maximum supported filename length and print it.
+#
+# Part of the gocryptfs test suite
+# https://nuetzlich.net/gocryptfs/
+
+NAME="maxlen."
+LEN=7
+
+while [ $LEN -le 10000 ]; do
+	touch $NAME 2> /dev/null || break
+	rm $NAME
+	NAME="${NAME}x"
+	let LEN=LEN+1
+done
+
+echo $LEN