#include<sys/stat.h>
#include<fcntl.h>
#include<inttypes.h>
#include<stdio.h>

#include<unistd.h>


struct Item
{
    int value;
    uint32_t next_pointer;
};


int
main(int argc, char *argv[])
{
    int exit_code = 0;
    int in_file = open(argv[1], O_RDONLY);
    if (-1 == in_file) {
        exit_code = 1;
        goto finally;
    }

    struct Item cur_item;
    int in_read;

    while ((in_read = read(in_file, &cur_item, sizeof(struct Item))) > 0) {
        printf("%d\n", cur_item.value);
        uint32_t cur_next_pointer = cur_item.next_pointer;
        if (cur_next_pointer == 0) {
            break;
        }
        else {
            int lseek_result = lseek(in_file, cur_next_pointer, SEEK_SET);
            if (lseek_result == -1) {
                exit_code = 3;
                goto finally;
            }
        }
    }

    if (-1 == in_read) {
        exit_code = 2;
        goto finally;
    }


finally:
    close(in_file);
    return exit_code;
}