diff --git a/ftok_test.go b/ftok_test.go
new file mode 100644
index 0000000..d9fae1a
--- /dev/null
+++ b/ftok_test.go
@@ -0,0 +1,29 @@
+// Copyright (c) 2020 Meng Huang (mhboy@outlook.com)
+// This package is licensed under a MIT license that can be found in the LICENSE file.
+
+package ftok
+
+import (
+	"testing"
+)
+
+func TestFtok(t *testing.T) {
+	key, err := Ftok("/tmp", 0x22)
+	if err != nil {
+		t.Error(err)
+	}
+	key1, err := Ftok("/tmp", 0x22)
+	if err != nil {
+		t.Error(err)
+	}
+	if key != key1 && key <= 0 {
+		t.Error(key, key1)
+	}
+}
+
+func TestStat(t *testing.T) {
+	_, err := Ftok("/tmp/hslam", 0x22)
+	if err == nil {
+		t.Error()
+	}
+}