Hex is a representation of a number. In order to do math, one must first convert it to something the computer considers a number. «hex» can do that.

You want to do 8 bit arithmetic while ignoring overflows. No problem, just filter out all but the lower 8-bits using «&».

You will need to convert the result back to hex. «sprintf "%02x"» will do that.

In reply to Re: Perl hex substraction by ikegami
in thread Perl hex substraction by inkubus

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