johngg@shiraz:~/perl > perl -Mstrict -Mwarnings -E '
my $str = q{abc  };
my $pck = pack q{Z*}, $str;
say sprintf q{%02x}, ord for split m{}, $pck;
say q{-} x 5;
say sprintf q{%02x}, ord for split m{}, unpack q{Z*}, $pck;'
61
62
63
20
20
00
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61
62
63
20
20