Printf long long int in C with GCC?

Question

How do I printf long long int and also unsigned long long int in C99 using GCC?

I have searched the other posts which suggest to use

Answer 1

For portable code, the macros in inttypes.h may be used. They expand to the correct ones for the platform.

E.g. for 64 bit integer, the macro PRId64 can be used.

int64_t n = 7;
printf("n is %" PRId64 "\n", n);