Dummy filter

x.php

<?php


class DummyFilter extends PHP_User_Filter
{
    private $_data;

    /* Called when the filter is initialized */
    function onCreate( )
    {
        $this->_data = '';
        return true;
    }

    /* This is where the actual stream data conversion takes place */
    public function filter($in, $out, &$consumed, $closing)
    {

        /* We read all the stream data and store it in
           the '$_data' variable
        */
        while($bucket = stream_bucket_make_writeable($in))
        {
            $this->_data .= $bucket->data;
            $this->bucket = $bucket;
            $consumed = 0;
        }

        /* Now that we have read all the data from the stream we process
          it and save it again to the bucket.
        */
        if($closing)
        {
            $consumed += strlen($this->_data);

            $this->bucket->data = $this->_data;
            $this->bucket->datalen = strlen($this->_data);
// echo 'here'; // just to show this code is actually ran.
            if(!empty($this->bucket->data))
                stream_bucket_append($out, $this->bucket);

            return PSFS_PASS_ON;
        }

        return PSFS_FEED_ME;
    }
}

stream_filter_register('dummy', 'DummyFilter');
include("php://filter/read=dummy/resource=y.php");
$f = new ReflectionFunction('foobar');
echo $f->getFileName();

y.php

<?php

function foobar() {
}