unpack makes it fairly clear that the code is dealing with octet (byte) oriented data without need for any further context. substr implies string handling with the possibility for utf/other encoding confusion. It's not that substr is flat out wrong in the context, just that it doesn't send as clear a message as unpack or the use of \C in a regex.

True laziness is hard work

In reply to Re^4: Pattern match not working sometimes by GrandFather
in thread Pattern match not working sometimes by dantheman1210

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