How to portably convert a string into an uncommon integer type?

Question

Some background: If I wanted to use for, for instance, scanf() to convert a string into a standard integer type, like uint16_t, I’d use SCNu1

Answer 1

If you are really concerned you can _assert(sizeof(pid_t) <= long) or whatever type you choose for your '%' stuff.

As explained in this answer, the spec says signed int. If 'int' changes, your '%u' by definition changes with it.