# Works on unix.
# Works on Windows.
# Works on Mac.

{
   open(my $fh, '<', $input_file)
      or die "Couldn't open file $input_file: $!\n";
   binmode($fh);
   my $buf = '';
   while (read($fh, $buf, 1024, length($buf))) {
      if (/\x0D\x0A/) { die("DOS files not allowed\n"); }
      $buf = substr($buf, -1);
   }
}


{      
   open(my $fh, '<', $input_file)
      or die "Couldn't open file $input_file: $!\n";

   while (<$fh>) {
      $total_lines++;
   }
}