A couple of points here...  First, 0 is obviously wrong for
3221225472 & 1073741824
But I don't know how you got 2147483648 either.
I get 1073741824 as 
3221225472 = 11000000000000000000000000000000
1073741824 = 01000000000000000000000000000000

11000000000000000000000000000000 & 
01000000000000000000000000000000 =
01000000000000000000000000000000

right?

Anyways, to your question  =P

First, if you check here: 
http://www.php.net/manual/en/language.types.integer.php

you will see that int's in PHP are always signed and that if
they exceed the max size for an int they are converted to a 
float.

Try running this on your server

<?php
$x = 3221225472;
$y = 1073741824;
echo "x = ";
var_dump($x);
echo "<BR>";
echo "y = ";
var_dump($y);
?>

I would be willing to bet that $x is a float and $y is an int, so
the bitwise operator can't compare them.  The only 
workaround I can offer you is this

<?php
$x = 3221225472;
$y = 1073741824;
$x = decbin($x);
$y = decbin($y);
$bitand = bindec($x & $y);
echo "Bitwise and gives $bitand";
?>

It's a bit kludgy but it forces both $x and $y to be compared
as binary numbers, which is what you want  =)

Sheridan Saint-Michel
Website Administrator
FoxJet, an ITW Company
www.foxjet.com


----- Original Message ----- 
From: "Alexey Prohorenko" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Tuesday, August 28, 2001 1:47 PM
Subject: [PHP] LONGINT... ? to be or not to be?...


> Hello,
> 
> I have one question. How can PHP work with longint (in C we call
> them "unsigned long") variables?
> F.e., I want to do next thing:
> 
> 65536 & 4096 = 0 (this is right)
> 65536 & 65536 = 65536 (again, everything is okay)
> 196608 & 65536 = 65536 (perfect, it works great)
> 
> but,
> 
> 3221225472 & 1073741824 = 0 (this is wrong, right answer isn't 0
>      but 2147483648)
> 
> So, can anybody help me with this? Any suggestions? 
> 
> Thanks, anyway. Looking forward your answers.
> Will check my mailbox every 5 minutes. :-)
> 
> -- 
> green
> [http://www.extrasy.net] 
> [http://www.unix-how-to.net]
> 
> -- 
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