public void Read(byte[] pv, int cb, IntPtr pcbRead)
{
if (position < 0L || position > _Cache.Length)
{
Marshal.WriteIntPtr(pcbRead, new IntPtr(0));
}
else
{
lock (_Lock)
{
_Cache.Read(pv, (int)position, cb, pcbRead);
position += pcbRead.ToInt64();
}
}
}
