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4. Function Pointers and Callbacks

Passing executable code references dynamically.

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Function pointers store the entry address of executable functions, powering polymorphism, virtual method tables (vtables), and asynchronous event dispatchers.

c
typedef int (*Comparator)(const void *, const void *);

void sort(void *base, size_t n, size_t size, Comparator cmp);

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Check your understanding

1. What is the primary use of function pointers in C systems programming?
Implementing dynamic dispatch, vtables, and custom callback routinesSpeeding up arithmeticAllocating memoryPreventing buffer overflows
2. How is a pointer to a function returning void and taking an int declared?
void (*fp)(int)void *fp(int)void (fp*)(int)*void fp(int)

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