#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>

int
main(int argc, char **argv)
{
   int  fd, length;
   off_t FileLength, position;
   char buf[1024];

   if (argc != 4){
      printf("Usage:  fileseek  <file>  <seek_position>  <#bytes>\n");
      exit (-1);
   }
   if ((fd = open(argv[1], O_RDONLY)) < 0) {
        perror(argv[1]);
        exit(1);
   }
   position = atoi(argv[2]);
   length = atoi(argv[3]);

   FileLength = lseek(fd, 0, SEEK_END);
   printf("File Length %d\n", FileLength);
   if ((position+length) > FileLength){
     printf("exceeds file limit\n");
     exit(0);
   }

   lseek(fd, position, SEEK_SET);
   read (fd, buf, length);
   write (1, buf, length);


}