$x = "\x2D\x05";
print unpack"n",$x;
[download]

#! perl -w

use strict;

my $string = uc " hack && pack || unpack";
#my $string = 'abcdefgh';
#my $string = uc 'abcdefgh';
#my $string = 'ABCD';

my @hex = unpack 'H*', $string;
print "H   @hex\n";

my @bytes = unpack 'C*', $string;
print "C   @bytes\n";

my @revbytes = reverse @bytes;
my $revbytes = pack 'C*', @revbytes;
print "C   $revbytes\n";


my @shorts = unpack 'S*', $string;
print "S   @shorts\n";

my @revshorts = reverse @shorts;
my $revshorts = pack 'S*', @revshorts;
print "S   $revshorts\n";


my @longs = unpack 'L*', $string;
print "L   @longs\n";

my @revlongs = reverse @longs;
my $revlongs = pack 'L*', @revlongs;
print "L   $revlongs\n";


my @bits = unpack 'B*', $string;
print "B   @bits\n";

my @revbits = reverse @bits;
my $revbits = pack 'B*', @revbits;
print "B   $revbits\n";

++$_ foreach @bytes;
my $bytes = pack 'C*', @bytes;
print "C   $bytes\n";

__END__

H   204841434b202626205041434b207c7c20554e5041434b
C   32 72 65 67 75 32 38 38 32 80 65 67 75 32 124 124 32 85 78 80 65 6
+7 75
C   KCAPNU || KCAP && KCAH 
S   18464 17217 8267 9766 20512 17217 8267 31868 21792 20558 17217
S   ACNP U||K AC P&&K AC H
L   1128351776 640032843 1128353824 2088509515 1347310880
L    UNPK || PACK && HAC
B   001000000100100001000001010000110100101100100000001001100010011000
+100000010100000100000101000011010010110010000001111100011111000010000
+0010101010100111001010000010000010100001101001011
B    HACK && PACK || UNPACK
C   !IBDL!''!QBDL!}}!VOQBDL
[download]

my $first = 0x2d;
my $second = 0x05;
my $string = sprintf("%02X%02X", hex($first), hex($second));
[download]

The basic idea is to sprintf() them, then concatenate the resultant strings.

I didn't explain this very clearly, sorry.

A set of 1, 2, 3 or 4 hex values are stored in one variable. If you printed the variable, you'd get whatever ASCII characters corresponded to the hex values. (There's probably a better way to explain this, but I don't really speak the language quite yet.)

Should I split() the variable, then sprintf, then concatenate?

Thanks once more...

---
donfreenut

Nah, use unpack at will.

You will have to pad them missing values:

$a = "\001"; #just another hex string
$a = ("\000" x (4-length($a))).$a; #Zero pad that string
print unpack 'L', $a; #Hey, that's one!
[download]

Jeroen
"We are not alone"(FZ)

print hex(c030), "\n";  # prints "49200"
[download]

Update: actually, on closer examination, you want to actually catenate 8-bit values into a big hex string. If this is the case, jeroenes has answered that above... I worked on a program awhile back in which I used something like:

$aschex.=uc(sprintf("%02x",ord($rawhex)));
[download]

--
Me spell chucker work grate. Need grandma chicken.