[racket] Keyboard polling and user packages

If you haven't already, you can try the following to disable any port 
buffering within Racket, but that doesn't help you if the OS (Windows 
and Posix-ish console stuff it's doing from the console window) isn't 
giving Racket raw, unbuffered access to keyboard input through stdin:

     (file-stream-buffer-mode my-port 'none)

If you were using almost anything other than Windows, you could just use 
"http://www.neilvandyke.org/racket-charterm/".

Other than that, you or someone could make a portable Racket 
text-terminal package that does stuff like uses the console API on 
Windows and tty on almost everything else.

BTW, you mention getting random bytes with variations on "read-bytes".  
That simply shouldn't happen with "read-bytes", but, when using 
variations on "read-bytes-avail!", only the first N count bytes it says 
it read will be valid in the bytestring.

Neil V.