gistfile1.c

/**
 *
 * main() -> func() -> hello()
 *
 */

#include <stdio.h>

void hello(int x)
{
    printf("What the F_CK:%d\n", x);
}

void func(int param, void (*func_ptr)(int))
{
    func_ptr(param);
}

int main()
{
    int param = 10;
    func(param, hello);
    return 0;
}