my $s = '0x010203';;

## Skip over the '0x' and extract the next 4 bytes
## then pack those 4 hex characters to binary
my $bin = pack 'H*', unpack 'xxA4', $s;;

## unpack the binary back to hex to check it worked.
print unpack 'H*', $bin;;
0102

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: converting ASCII hex into binary by BrowserUk
in thread converting ASCII hex into binary by gri6507

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