C Programming for Low Level Hardware

I think it depends, trivial min() and max() style functions are very common and considered acceptable, though I guess you could have been using inline for the last two decades...

The only time I got any serious usage out of preproc functions was writing a driver for an AT-command set cellular modem which involved writing a ton of repetitive code for each AT command.

I think I would prefer this sort of content in wrtten form though, cause I do it so seldom, I always need to look up syntactic specials like 'stringizing' where I even tend to forget the names of the concepts :)