$setbits = unpack "%32b*", $selectmask;
should be:
$setbits = unpack "%32b*", $packedmask;
so:
$setbits = unpack('%32b*', pack('N', $selectmask));
does the trick
print(unpack("%32b*", pack('N', 0x00500011)), $/);  # 4

In reply to Re^3: how to pack bits, flags and masks by ikegami
in thread how to pack bits, flags and masks by anadem

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