in reply to String to UTF-8

Because at least one of your character codes is 255 or higher, your string will internally be encoded in UTF-8. However, Perl's pure string manipulation routines work transparently, whether a string is in UTF-8 or in a single byte encoding, such as split, chr, ord, length. So you can achive what you want by using rather classic code — meaning it doesn't look like anything special: 
   for my $i (0 .. length($str)-1) {
       print " " if $i;
       print ord substr $str, $i, 1;
   }
   print "\n";

[download]
or, like Juerd mentioned: 
   print join " ", map ord, split //, $str;
   print "\n";

[download]

n.b. For some mysterious reason, the latter code works as it should in perl 5.8.4, but fails in 5.6.1. It smells like a Unicode related perl bug. 

Malformed UTF-8 character (unexpected non-continuation byte 0x00 after
+ start byte 0xc9) in ord at test.pl line 6.
Malformed UTF-8 character (unexpected continuation byte 0xbc) in ord a
+t test.pl line 6.
Malformed UTF-8 character (unexpected non-continuation byte 0x00 after
+ start byte 0xc5) in ord at test.pl line 6.
Malformed UTF-8 character (unexpected continuation byte 0xbf) in ord a
+t test.pl line 6.
66 0 0 105 0 0

[download]

If, OTOH, you choose to use pack/unpack, it'll work on the raw bytes, so it will make a difference whether the string is in single-bye encoding (each character is a byte), or in UTF-8. 

   print join " ", unpack "C*", $str;
   print "\n";

[download]

In Section Seekers of Perl Wisdom