1 files changed, 13 insertions, 0 deletions
diff --git a/src/runtime/export_darwin_test.go b/src/runtime/export_darwin_test.go
new file mode 100644
index 0000000..e9b6eb3
--- /dev/null
+++ b/src/runtime/export_darwin_test.go
@@ -0,0 +1,13 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+func Fcntl(fd, cmd, arg uintptr) (uintptr, uintptr) {
+	r := fcntl(int32(fd), int32(cmd), int32(arg))
+	if r < 0 {
+		return ^uintptr(0), uintptr(-r)
+	}
+	return uintptr(r), 0
+}