So far we hard coded /dev/ttyUSB0 - which is a good starting point in
Linux but not so useful on Windows or MacOS. This was now moved into one
of our OS helper functions with (somewhat) reasonable defaults.
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
This adds tested code for Linux and Mac OS, implementing the api that
Linus suggested.
The Windows code was moved into its own file, but hasn't even been compile
tested, yet.
In order to have just one interface to set or get a preference value we
encode TRUE as (void *) 1 and FALSE as NULL. This works consistently on
all platforms and regardless of whether we have 32 or 64 bit.
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>