int main(int argc, char *argv[])
{
	register_callback(my_callback, "hello world");
	register_callback_pre(my_callback_pre, "hello world");
	register_callback_post(my_callback_post, "hello world");
	return 0;
}
int main(int argc, char *argv[])
{
	char p[] = "hello world";
	register_callback(my_callback, p);
	register_callback_pre(my_callback_pre, p);
	register_callback_post(my_callback_post, p);
	return 0;
}
int main(int argc, char *argv[])
{
	struct undefined *handle = NULL;

	register_callback(my_callback, handle);
	register_callback_pre(my_callback_pre, handle);
	register_callback_post(my_callback_post, handle);
	return 0;
}
int main(void)
{
	struct undefined *handle = NULL;

	register_callback(my_callback, handle);
	register_callback_pre(my_callback_pre, handle);
	register_callback_post(my_callback_post, handle);
	return 0;
}