Pack and unpack 64 bit integer
<p>I have the following code:</p>

<pre><code>$packed = pack('i',PHP_INT_MAX);
echo unpack('i', $packed)[1];
</code></pre>

<p>As result I get <code>-1</code></p>

<p>I'm using <code>PHP 5.4.6-1ubuntu1.1 (cli) (built: Nov 15 2012 01:18:34)</code>
and my <code>PHP_INT_MAx</code> is equal to <code>9223372036854775807</code></p>

<p>Is there any way to work with <code>pack</code> function and 64 bit integers?</p>
