What does “typedef void (*Something)()” mean

Question

I am trying to understand what this means, the code I am looking at has

in .h

typedef void (*MCB)();
static MCB     m_process;

in .

Answer 1

It's a function pointer. You get a SEGMENTATION FAULT because you are trying to make a call to a function which address is invalid (NULL).

According to your specific sample, the function should return no value (void) and should receive no parameters ().

This should work:

void a()
{
    printf("Hello!");
}

int main(int arcg, char** argv)
{
    m_process = a;
    m_process(); /* indirect call to "a" function, */
    // Hello!
}

Function pointers are commonly used for some form of event handling in C. It's not its only use though...