Using mmap read only

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
 
#define FILEPATH "/tmp/mmapped.bin"
#define NUMINTS  (1000)
#define FILESIZE (NUMINTS * sizeof(int))
 
int main(int argc, char *argv[])
{
    int i;
    int fd;
    int *map;  /* mmapped array of int's */
 
    fd = open(FILEPATH, O_RDONLY);
    if (fd == -1) {
    perror("Error opening file for reading");
    exit(EXIT_FAILURE);
    }
 
    map = mmap(0, FILESIZE, PROT_READ, MAP_SHARED, fd, 0);
    if (map == MAP_FAILED) {
    close(fd);
    perror("Error mmapping the file");
    exit(EXIT_FAILURE);
    }
    //map[7] = 876;
    /* Read the file int-by-int from the mmap
     */
    for (i = 1; i <=NUMINTS; ++i) {
    printf("%d: %d\n", i, map[i]);
    }
 
    if (munmap(map, FILESIZE) == -1) {
    perror("Error un-mmapping the file");
    }
    close(fd);
    return 0;
}