It doesn't make much sense to me either. I can suggest a workaround, however, and leave the technical explanation to someone who understands it better than I do.

Instead of
sprintf "%1x", $var;
use
sprintf "%2x", $var;

This will give two nybbles (a full byte) so pack and unpack give the expected answer.

Update: Changed bytes to nybbles - Doh!

Update 2: ++ greenFox for pointing out the why.

In reply to Re: Pack/unpack irregularity by jsprat
in thread Pack/unpack irregularity by thor

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