Public Overloads Sub Write( _
   ByVal buffer() As Byte, _
   ByVal offset As Integer, _
   ByVal length As Integer, _
   ByVal signal As EventWaitHandle _
) 

public void Write( 
   byte[] buffer,
   int offset,
   int length,
   EventWaitHandle signal
)

using (ManualResetEvent mre = new ManualResetEvent(false))
using (TestStream io = new TestStream())
using (BackgroundWriter wtr = new BackgroundWriter(io))
{
    wtr.Write(new byte[100], 0, 100, mre);
    Assert.IsTrue(mre.WaitOne(60000, false));
    Assert.AreEqual(100, io.Position);
    Assert.AreEqual(100, io.Length);
}

Using mre As New ManualResetEvent(False)
    Using io As New TestStream()
        Using wtr As New BackgroundWriter(io)
            wtr.Write(New Byte(100) {}, 0, 100, mre)
            Assert.IsTrue(mre.WaitOne(60000, False))
            Assert.AreEqual(100, io.Position)
            Assert.AreEqual(100, io.Length)
        End Using
    End Using
End Using