[fpc-pascal] Sending break on (Windows) serial comms

[Marco van de Voort]

In our previous episode, Mark Morgan Lloyd said:
> Marco, I see you had a StackOverflow question on this a year or so ago. 
> Did you ever get anywhere with it in practice?

It was an idea to lower the overhead and improve the reliability of our
serial protocol. (because of the out of band information is guaranteed
unique and can't happen in the datastream)

But if you can't insert the break cleanly into the character stream, it is
useless for protocol purposes I guess. And it was not worth centering the
rest of the application around it.

I did't have any confidence in the solutions presented (just reset the
connection and pauze) because both the pauze is not reliable in length on
preemptive systems like Windows, and the damage to the FIFOs is a problem,
since that would negate the size advantages.

I never pursued it further.