I have the following code in PHP 

```
$ch = curl_init("http://blog.com");
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$output = curl_exec($ch);      
curl_close($ch);
echo $output;

```

I am trying to import the block of code in between `<div id="content">` and `</div>` I would like to know the best way of extracting this code.