Defining variables of fixed size in Nios Softaware

THere's multiple solutions to that:

a) define your own variable declarations, and use them in your code......could be a problem if you need to re-use existing code, but you can easily redefine it when you move your code to a different target.

b) some projects/Compilers/tools already bring predefined types like BYTE, WORD, DWORD...... this might or might not work when using your code to other tools/targets, but you be optimistic to have these types on a new target (if not, you can define them to your needs).

c) use alt_types.h, which defines alt_u8, alt_u16, alt_u32, alt_s8, alt_s16, alt_s32 and so on.....accounts for altera tools only, apart from that same as (b).