#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdint.h>
#include <syscall.h>
#include <unistd.h>
#include <sys/mman.h>
#include <stdio.h>
#include <error.h>
#include <stdlib.h>
#include <string.h>

#define NAME_FILE "/tmp/filefile1"
#define PATH_STR "/tmp/filefile2"

int main()
{
	int ret;
	int fd;
	char *name;
	ssize_t len;

	fd = open(NAME_FILE, O_RDWR | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR,
			0700);
	if (fd < 0) {
		perror("open1");
		abort();
	}
	len = write(fd, PATH_STR, strlen(PATH_STR) + 1);
	if (len < strlen(PATH_STR) + 1) {
		abort();
	}
	/* mmap the name file which will be used as input string for openat
	 * filename parameter, triggering a page fault because the pages of this
	 * mapping are not populated in the page cache.
	 */
	name = mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
	if (name == MAP_FAILED) {
		perror("mmap");
		abort();
	}
	openat(42, name, 0, 0);
}