in reply to Confession of a Perl Hacker

The Cookbook uses the following example (listed on page 4)
# get a 5-byte string, skip 3, grab 2 8-byte strings, then the rest ($leading, $s1, $s2, $trailing) = unpack("A5 x3 A8 A8 A*",$data);
x3 meaning to "ignore" 3 bytes (jump forwards), while Xm means to jump m bytes back.
A5 meaning to "get" 5 Ascii (space padded) bytes.
Another example would be to pack/unpack to/from binary or hexadecimal.

$string = "My uncle John is Jamaica"; $binary=unpack("B*",$string);


Similar for Hexadecimal...
$string = "My uncle John is Jamaica"; $hexadecimal=unpack("H*",$string); $string=pack("H*",$hexadecimal);
Anyway, those were just the simple examples =)

... Quidquid perl dictum sit, altum viditur.