use Encode;
...
$x = chr(65533);
$y = Encode::encode('utf-8', $x); # -> "\x{aa}\x{42}\x{fe}"

##</code><code>##

$y = Encode::decode('some encoding', $x);
binmode STDOUT, ":bytes"; print $x;
...

##</code><code>##

$y = Encode::encode('some encoding', $x);
$n = rindex($x, "\N{WHITE SMILEY FACE}"); # need: use charnames ':full';
...