Question: what is the difference between int and int32_t?
Answer: Plain int is quite a bit different from the others. Where int8_t and int32_t each have a specified size, int can be any size >= 16 bits. ... On the other hand, int is guaranteed to be present in every implementation of C, where int8_t and int32_t are not. It's probably open to question whether this matters to you though.