#define _GNU_SOURCE
#define _FILE_OFFSET_BITS 64

#include <fcntl.h>
#include <sys/types.h>
#include <unistd.h>

int main ()
{
    char ch;
    loff_t res;
    int fd;
    loff_t offset;
    int i;

    offset = (unsigned long)5735142 * 512;

    fd = open ("/dev/hdf8", O_RDONLY);

    res = lseek64 (fd, 0, SEEK_END);
    if (res < 0) {
        printf ("cannot lseek64 %m\n");
        return 1;
    } else {
        printf ("lseek64 SEEK_END to %Lu\n", res);
    }

    for (i = 0; i < 12; i++) {
        res = lseek64 (fd, offset, SEEK_SET);
        if (res < 0) {
            printf ("cannot lseek64 to %Lu", offset);
	    return 1;
        } else {
            printf ("lseek64 to %Lu\n", res);
        }

        if (read (fd, &ch, 1) < 0) {
            printf ("cannot read %m\n");
//            return 1;
        } else {
            printf ("read a byte\n");
        }

        offset -= 512;
    }

    return 0;
}