Description:
------------
dir_readdir seems to cause a crash when used with readdir(). Code below is based on the \ext\standard\tests\file\userdirstream.phpt test, but instead of using scandir() which appears to work fine, the manual looping causes an application exception.

Reproduce code:
---------------
class test {
	public $idx = 0;

	function dir_opendir($path, $options) {
		print "Opening\n";
		$this->idx = 0;
		return true;
	}

	function dir_readdir() {
		$sample = array('first','second','third','fourth');
		if ($this->idx >= count($sample)) 
			return false;
		else 
			return $sample[$this->idx++];
	}

	function dir_rewinddir() {
		$this->idx = 0;
		return true;
	}

	function dir_closedir() {
		print "Closing up!\n";
		return true;
	}
}
stream_wrapper_register('test', 'test');
$dh = opendir('test://example.com/path/to/test');
if ($dh) {
	while (($f = readdir($dh)) !== FALSE)
		echo $f, "\n";
}


Expected result:
----------------
Opening
first
second
third
fourth

without an application exception

Actual result:
--------------
Opening
first
second
third
fourth

with an application exception