Beefy Boxes and Bandwidth Generously Provided by pair Networks
go ahead... be a heretic
 
PerlMonks  

Re: pack and unpack trouble

by ikegami (Patriarch)
on Dec 22, 2011 at 16:28 UTC ( [id://944808]=note: print w/replies, xml ) Need Help??


in reply to pack and unpack trouble

$mCrc = $mPolyTable[ ( $mCrc ^ $iByteArray[$x] ) & 0xFF ];

[download]

The closest pack equivalent to a (byte)val would be 

unpack('C', substr(pack('J', $val), 0, 1))

[download]

or 

unpack('C', substr(pack('J', $val), -1, 1))

[download]

depending on your machine. That could be made portable as 

unpack('C', substr(pack('J<', $val), 0, 1))

[download]

which simplifies to 

unpack('C', pack('J<', $val))

[download]

But what a waste.

Update: Added the content underneath the bar.

Replies are listed 'Best First'.
Re^2: pack and unpack trouble
by scoobyrico (Beadle) on Dec 22, 2011 at 18:30 UTC
    Excellent! as a follow up, if I want to take 1365238130 to 515FE172? Upate: I would have thought it was hex(1365238130) but that gets me 83301204272. So clearly I am doing something wrong.
    In C# 
    uint temp = 1365238130;
System.Console.WriteLine(temp.ToString("X"));

    [download]
[reply]
[d/l]
      Adapted from perlfaq4: How do I convert between numeric representations/bases/radixes? 
      my $hex_string = sprintf '%X', 1365238130;

      [download]
[reply]
[d/l]

      hex converts *from* hex to a number.

      sprintf '%X', $n will represent a number using hex.

[reply]
        Thanks so much! I had totally forgotten about sprintf
[reply]

In Section Seekers of Perl Wisdom

Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?

www.com | www.net | www.org
Node Status?
node history
Node Type: note [id://944808]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? • Last hour • Other CB clients
Other Users?
Others browsing the Monastery: (7)
As of 2024-04-16 07:49 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found