The example above (which I copied and ran) is not reading or writing to a file except STDOUT. Can binmode effect STDIN/STDOUT/STDERR?

The scalar assignments exhibit this behavior (assignments mind you) as shown (asked) in the original question above. Can anyone tell me why this is?

My code example above was given as a way to store \x0a\x0d for use by the reader program since flipping it any other way with double quote interpolation (without PACK) elludes me. Is there another way to store hex 0a0d without using pack?