How to get the value of individual bytes of a variable?

Question

I know that to get the number of bytes used by a variable type, you use sizeof(int) for instance. How do you get the value of the individual bytes used when you

Answer 1

You could make use of a union but keep in mind that the byte ordering is processor dependent and is called Endianness http://en.wikipedia.org/wiki/Endianness

#include 
#include 

union my_int {
   int val;
   uint8_t bytes[sizeof(int)];
};

int main(int argc, char** argv) {
   union my_int mi;
   int idx;

   mi.val = 128;

   for (idx = 0; idx < sizeof(int); idx++)
        printf("byte %d = %hhu\n", idx, mi.bytes[idx]);

   return 0;
}