func TestDup(t *testing.T) {
file, err := ioutil.TempFile("", "TestDup")
if err != nil {
t.Fatalf("Tempfile failed: %v", err)
}
defer os.Remove(file.Name())
defer file.Close()
f := int(file.Fd())
newFd, err := unix.Dup(f)
if err != nil {
t.Fatalf("Dup: %v", err)
}
err = unix.Dup2(newFd, newFd+1)
if err != nil {
t.Fatalf("Dup2: %v", err)
}
b1 := []byte("Test123")
b2 := make([]byte, 7)
_, err = unix.Write(newFd+1, b1)
if err != nil {
t.Fatalf("Write to dup2 fd failed: %v", err)
}
_, err = unix.Seek(f, 0, 0)
_, err = unix.Read(f, b2)
if err != nil {
t.Fatalf("Read back failed: %v", err)
}
if string(b1) != string(b2) {
t.Errorf("Dup: stdout write not in file, expected %v, got %v", string(b1), string(b2))
}
}
func TestSeekFailure(t *testing.T) {
_, err := unix.Seek(-1, 0, 0)
if err == nil {
t.Fatalf("Seek(-1, 0, 0) did not fail")
}
str := err.Error() // used to crash on Linux
t.Logf("Seek: %v", str)
if str == "" {
t.Fatalf("Seek(-1, 0, 0) return error with empty message")
}
}