Can I pass a reference to a variable into a function defined to take a normal variable?
<p>I need to use the PHP function <code>strtolower($str)</code> to put a large string in all-lower-case.  Since the string is large, I would have liked if it could be taken as a reference and operated on.  For example (though this doesn't work):</p>

<p>I wanted to do:</p>

<pre><code>$myLargeString = PopulateString();
strtolower(&amp;$myLargeString);
</code></pre>

<p>instead of:</p>

<pre><code>$myLargeString = PopulateString();
$myLargeString = strtolower($myLargeString);
</code></pre>

<p>is there any trick that would let me lower-case a string by reference to save some speed, or maybe another function I should be looking at?  I'm not particularly strong in PHP so I'm not sure what to look for.</p>
