The .NET Framework 4.8 Stream.CopyToAsync() method has a default buffer size of 81,920. I think that buffer size is fine but I also want to pass a cancellation token. To pass a token I also have to provide a buffer size.

stream.CopyToAsync(fs, 81920, token);

Is the default buffer size defined as a constant that I can use or do I have to create my own constant?