Get curl CURLOPT_USERAGENT

You don't have to use curl since Laravel has the information as well for you. You can for example use

// In your controller
public function index(Request $request)
{
    $request->header('User-Agent');

}

You can also access this information somewhere else using the request helper or facade

request()->header('User-Agent');
Request::header('User-Agent');

that is only case when we pass header like

curl_setopt($this->process, CURLOPT_HTTPHEADER,$headers);

But if we pass user agent like

curl_setopt($this->process, CURLOPT_USERAGENT, $_SERVER['HTTP_USER_AGENT']);

then what??