How to generate a short eight character md5 signature in perl, similar to what is done by the OpenSSL utility "openssl -x509 -hash -noout < certfile" The shorter signature increases the odds of collisions, but takes up less space.
use Digest::MD5;

my $fh;

if (@ARGV) {
  my $file = shift;

  open $fh, $file or die "error: could not open $file: $!\n";
  binmode $fh;
} else {
  $fh = *STDIN;
}

printf "%08x\n", unpack "N", Digest::MD5->new->addfile($fh)->digest;

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In reply to md5 short hash by thrig

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