how to define a pointer to function that returns a pointer to function

Question

How to define a pointer to function that returns a pointer to function?

typedef int(*a)(int,int);
a (*b)(int,int);

Why this can work,but the following can't work?

(int(*a)(int,int) ) (*b)(int,int);

or

int(*)(int,int) (*b)(int,int);

or

( int(*)(int,int) ) (*b)(int,int);

If you can, just stick with the typedef. Without it the syntax is wildly confusing - so much so that I don't want to attempt an answer from my phone at the risk of messing it up. — Chris Lutz
– Chris Lutz, Commented Feb 25, 2012 at 5:06

Justin Peel · Accepted Answer · 2012-02-25 05:36:45Z

4

Here is the correct way to do it:

int (*(*b)(int,int))(int,int);

You can compile the following code that demonstrates using both of the methods. I would personally use the typedef method for clarity.

#include <stdio.h>

int addition(int x,int y)
{
    return x + y;
}

int (*test(int x, int y))(int,int)
{
    return &addition;
}

typedef int (*a)(int, int);

int main()
{
    a (*b)(int,int);
    int (*(*c)(int,int))(int,int);
    b = &test;
    c = &test;
    printf(b == c ? "They are equal!\n" : "They are not equal :(\n");
}

edited Feb 25, 2012 at 5:36

answered Feb 25, 2012 at 5:13

Justin Peel

47.1k6 gold badges62 silver badges81 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

how to define a pointer to function that returns a pointer to function

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related