printf the last Byte of a hex value in C

Question

I have a simple question. The code is really short so I just post it here

#include 
int main(int argc, const char * argv[])
{

    long int p;

           


        

Answer 1

First convert to unsigned:

unsigned char q = *(unsigned char *)(p);
printf("%02X", q);

(Otherwise, if your char is signed, the variadic default promotion converts the value to int, and the result may be negative.)