$packed = join "", map { chr() } (0x01..0x20);
$plen = length( $packed );
$tmpl = "a" . $plen;

print "unpacking $plen bytes using (a): ";
$unpacked = unpack( $tmpl, $packed );
$result = ( $packed eq $unpacked ) ? "same" : "different";
print "$result\n";'