How do I return multiple values from a function in C?

Question

If I have a function that produces a result int and a result string, how do I return them both from a function?

As far as I can tell I can

Answer 1

Since one of your result types is a string (and you're using C, not C++), I recommend passing pointers as output parameters. Use:

void foo(int *a, char *s, int size);

and call it like this:

int a;
char *s = (char *)malloc(100); /* I never know how much to allocate :) */
foo(&a, s, 100);

In general, prefer to do the allocation in the calling function, not inside the function itself, so that you can be as open as possible for different allocation strategies.