I have a function that receive a $\_POST (your content: a variable 'xml' in a xml format).

I've tried this:

```
function call($_POST) {    
    $xml = $_POST['xml'];    
    $doc = simplexml_load_string($xml); 
}

```

But when i try write the final variable in a file, nothing is written.
(And i've already tried treat the post as an array, but doesn't work too).

Thanks,