#include <fcntl.h>
#include <memory.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <unistd.h> 

int main(int argc, char *argv[])
{
	int fd;
	off_t size;
	char *mapping;
	unsigned r;
	unsigned i;

	if (argc != 2) {
		printf("Usage: %s <file>\n", argv[0]); 
		return EXIT_FAILURE;
	}

	fd = open(argv[1], O_RDONLY, 0);
	size = lseek(fd, 0, SEEK_END); 

	mapping = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);

	/* access (read) the file a couple of times*/
	for (r = 0; r < 4; r++) {
		for (i = 0; i < size; i++) {
			char t = mapping[i];
		}
	}

	munmap(mapping, size);
	close(fd);

	return EXIT_SUCCESS;
}