#define _GNU_SOURCE

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <dlfcn.h>

static void *load_sym(const char *name)
{
	void *addr;
	const char *msg;

	(void) dlerror();
	addr = dlsym(RTLD_NEXT, name);
	if ((msg = dlerror()))
	{
		fprintf(stderr, "dlsym(%s): %s\n", name, msg);
		abort();
	}
	fprintf(stderr, "dlsym(%s) = %p\n", name, addr);
	return addr;
}

int (*next)(const char *pathname, int flags, mode_t mode) = NULL;

int
main(int ac, const char **av)
{
	int     fd;

	if (ac != 2)
		return 1;

	next = load_sym(av[1]);
	fd = next("/etc/inittab", O_RDONLY, 0);
	close(fd);

	return 0;
}