1 files changed, 78 insertions, 0 deletions
diff --git a/src/runtime/fds_test.go b/src/runtime/fds_test.go
new file mode 100644
index 0000000000..8d349ec7eb
--- /dev/null
+++ b/src/runtime/fds_test.go
@@ -0,0 +1,78 @@
+// Copyright 2023 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.
+
+//go:build unix
+
+package runtime_test
+
+import (
+	"internal/testenv"
+	"os"
+	"strings"
+	"testing"
+)
+
+func TestCheckFDs(t *testing.T) {
+	if *flagQuick {
+		t.Skip("-quick")
+	}
+
+	testenv.MustHaveGoBuild(t)
+
+	fdsBin, err := buildTestProg(t, "testfds")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	i, err := os.CreateTemp(t.TempDir(), "fds-input")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err := i.Write([]byte("stdin")); err != nil {
+		t.Fatal(err)
+	}
+	if err := i.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	o, err := os.CreateTemp(t.TempDir(), "fds-output")
+	if err != nil {
+		t.Fatal(err)
+	}
+	outputPath := o.Name()
+	if err := o.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	env := []string{"TEST_OUTPUT=" + outputPath}
+	for _, e := range os.Environ() {
+		if strings.HasPrefix(e, "GODEBUG=") || strings.HasPrefix(e, "GOTRACEBACK=") {
+			continue
+		}
+		env = append(env, e)
+	}
+
+	proc, err := os.StartProcess(fdsBin, []string{fdsBin}, &os.ProcAttr{
+		Env:   env,
+		Files: []*os.File{},
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	ps, err := proc.Wait()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if ps.ExitCode() != 0 {
+		t.Fatalf("testfds failed: %d", ps.ExitCode())
+	}
+
+	fc, err := os.ReadFile(outputPath)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if string(fc) != "" {
+		t.Errorf("unexpected file content, got: %q", string(fc))
+	}
+}