}

func TestCmpReaders(t *testing.T) {
	{
		r1 := bytes.NewReader([]byte("abc"))
		r2 := bytes.NewReader([]byte("abc"))
		ok, msg := cmpReaders(r1, r2)
		if !(ok && msg == "") {
			t.Fatalf("unexpected")
		}
	}

	{
		r1 := bytes.NewReader([]byte("abc"))
		r2 := bytes.NewReader([]byte("abcd"))
		ok, _ := cmpReaders(r1, r2)
		if ok {
			t.Fatalf("unexpected")
		}
	}

}

func lockFileEx(h syscall.Handle, flags, locklow, lockhigh uint32, ol *syscall.Overlapped) (err error) {
	reserved := uint32(0)
	r1, _, e1 := syscall.Syscall6(procLockFileEx.Addr(), 6, uintptr(h), uintptr(flags),
		uintptr(reserved), uintptr(locklow), uintptr(lockhigh), uintptr(unsafe.Pointer(ol)))
	if r1 == 0 {
		if e1 != 0 {
			err = error(e1)
		} else {
			err = syscall.EINVAL
		}
	}
	return