#! /usr/bin/perl

use autodie;

my $ZERO = "\0" x 2048;
for my $f (@ARGV) {
  open my $fh, "<", $f; binmode $fh;
  my $buf;
  my $i = 0;
  SECTOR: for (;;) {
    my $n = read $fh, $buf, 2048; last SECTOR if $n < 2048;
    my $head;
    if ($buf eq $ZERO) { $head = "---"; }
    else { $head = unpack "H*", substr $buf, 0, 16; }
    printf "%8d: %s\n", $i++, $head;
  }
}