in reply to Hex to Octet

perl -le '$_ = pop; s/\A..//; $_ = "0$_" if length() % 2; print join ".", reverse unpack("A2" x (length() / 2), $_);'

Put the hex value you want to convert as its single argument.

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I wanted to explore how Perl's closures can be manipulated, and ended up creating an object system by accident.
-- Schemer

Note: All code is untested, unless otherwise stated