PHP source code for inbuilt functions
<p>Are PHP functions such as <code>in_array()</code> written in PHP Or C ? Where can i find the source code for these ? Or do i need to be part of the PHP team to get get access to these ? After several googling attempts i am unable to locate any documentation on the matter.     </p>

<p>Edit: I'm fully aware that PHP is open source, the question is more about whether they are written in PHP or native C and how i can get access to the code. </p>
