Question

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What is the point of function pointers?

I saw this code

 void (*foo)(int);

And I understood that is pointer to function.

Why should I point to another function what does it give me?

Answer 1

You can use it to store a handler function that can be changed according the program flow, like the comparison function supplied to qsort.

void (*my_handler)(int);

void set_handler(void(*fn)(int)) {
    my_handler = fn;
}

void do_stuff() {
    // ...
    my_handler(x); // using a custom handler
}

if (something) {
    set_handler(my_function_1);
}
else set_handler(my_function_2);    

do_stuff();