use strict ;
  use warnings ;

  use Encode qw(_utf8_on) ;

  for my $r ("\xC2\xAB \x61\x68\x61 \xC2\xBB", "\xC2\x7E \x61\x68\x61 \x80\xC0") {
    for my $utf (0..1) {
      _utf8_on($r) if $utf ;
      printf "'%s', %d/%d %s\n", raw(unpack('a*', $r)) ;
    } ;
  } ;

  sub raw {
    my ($s) = @_ ;

    my ($b, $q) ;
    { use bytes ;
      $b = length($s) ;
      $q = join '', map { ($_ >= 0x20) && ($_ <= 0x7E) ? chr($_) : sprintf('\\x%02X', $_)
                        } unpack('C*', $s) ;
    } ;

    return ($q, length($s), $b, utf8::is_utf8($s) ? 'utf8' : 'not utf8') ;
  } ;