Then, no, you are not using sprintf() correctly.
The way you have c defined, it is a pointer. What does it point to? Nothing. And, yet, you as sprintf() to write to the memory pointed to by c.
char c[4];
sprintf(c, "%d", red);
would work.
Then, no, you are not using sprintf() correctly.
The way you have c defined, it is a pointer. What does it point to? Nothing. And, yet, you as sprintf() to write to the memory pointed to by c.
char c[4];
sprintf(c, "%d", red);
would work.