[mistrial9]

this is a pointer-based language so there are lots of ways to solve that, but you know that already.. this is a setup question.. of course its not useful to re-invent critical, secure functions over and over yet, what if I am not writing critical, secure functions anyway?

I would choose a key type that is natural to the environment and problem.. unsigned integers are useful. Which unsigned integer size? there are only a couple of practical answers to that.. unless there is some massive dataset, use a 32bit unsigned integer, like so much of the software does right now.