public void ChangeLengthFails()
        {
            SparseMemoryStream memStream = new SparseMemoryStream();

            memStream.SetLength(2);

            ThreadSafeStream tss = new ThreadSafeStream(memStream);

            Assert.Equal(2, tss.Length);

            try
            {
                tss.SetLength(10);
                Assert.True(false, "SetLength should fail");
            }
            catch (NotSupportedException)
            {
            }
        }