diff --git a/config.go b/config.go
index 8dfe0af..7260089 100644
--- a/config.go
+++ b/config.go
@@ -344,7 +344,7 @@ func (c *Config) OpenLevel(parent *Config, level ConfigLevel) (*Config, error) {
 }
 
 // OpenOndisk creates a new config instance containing a single on-disk file
-func OpenOndisk(parent *Config, path string) (*Config, error) {
+func OpenOndisk(path string) (*Config, error) {
 	cpath := C.CString(path)
 	defer C.free(unsafe.Pointer(cpath))
 
diff --git a/config_test.go b/config_test.go
index 196d4ad..398236e 100644
--- a/config_test.go
+++ b/config_test.go
@@ -13,7 +13,7 @@ func setupConfig() (*Config, error) {
 		err error
 	)
 
-	c, err = OpenOndisk(nil, tempConfig)
+	c, err = OpenOndisk(tempConfig)
 	if err != nil {
 		return nil, err
 	}