Inheritance example using C

Animal.c

#include <stdio.h>
#include <string.h>
#include "Animal.h"

void Animal_Ctor(Animal* pa)
{
	pa->pfspeak=Animal_Speaking;
}

void Animal_Speaking(Animal* pa)
{
	puts("Animal Speaking..");
}

void Dog_Ctor(Dog* pd,const char* n)
{
	Animal_Ctor((Animal*)pd);
	((Animal*)pd)->pfspeak=Dog_Speaking;
	strcpy(pd->name,n);
}

void Dog_Speaking(Dog* pd)
{
	printf("%s says Woof Wood\n",pd->name);
}

void Cat_Ctor(Cat* pc,const char* n)
{
	Animal_Ctor((Animal*)pc);
	((Animal*)pc)->pfspeak=Cat_Speaking;
	strcpy(pc->name,n);
}

void Cat_Speaking(Cat* pc)
{
	printf("%s says Meow Meow\n",pc->name);
}

Animal.h

#ifndef ANIMAL_H
#define ANIMAL_H

typedef struct Animal
{
	void (*pfspeak)();
}Animal;

void Animal_Ctor(Animal* pa);
void Animal_Speaking(Animal* pa);


typedef struct Dog
{
	Animal a;
	char name[255];
}Dog;

void Dog_Ctor(Dog* pd,const char* n);
void Dog_Speaking(Dog* pa);


typedef struct Cat
{
	Animal a;
	char name[255];
}Cat;

void Cat_Ctor(Cat* pc,const char* n);
void Cat_Speaking(Cat* pc);


#endif

main.c

#include <stdio.h>
#include "Animal.h"

void MakeAnimalSpeak(Animal* pa)
{
	pa->pfspeak(pa);
}

int main()
{
	Animal a;
	Dog d;
	Cat c;

	Animal_Ctor(&a);
	Dog_Ctor(&d,"Milo");
	Cat_Ctor(&c,"Kitty");

	MakeAnimalSpeak(&a);
	MakeAnimalSpeak((Animal*)&d);
	MakeAnimalSpeak((Animal*)&c);

	return 0;
}