I'm far from an expert on pack/unpack myself. In fact, I saw your post as a chance to learn a little myself! I think perhaps you should make the 'C' an 'I' in your templates, and then specify the hex data as 16 bits in length. The following worked for me...at least I got all 8 bytes of the hex back. 

$record[0] = pack ("A2IA7", "RT", 7, "testing");
$record[1] = pack ("A2IH16", "CD", 16, "01020304FFDDEC19");

# Prints ASCII fields fine, truncates hex
for (my $i=0; $i<2; $i++) {
  my ($kw) = unpack("A2", $record[$i]);
  my ($rdata) = unpack("x2I/$kwfmt{$kw}", $record[$i]);
  print "$kw $rdata\n";
}

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In reply to Re: Length of unpacked string for "hex" data by wedgef5
in thread Length of unpacked string for "hex" data by SirBones

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