PHP: How to check for timeout exception in Guzzle 4?

Question

Guzzle throws an exception if an error occured during the request. Unfortunately, there does not seem to be an error specific to timeouts - which is important for me as I know that those can ocassionally occur. I'd like to retry the corresponding request and need to able to tell if the error occured due to a timeout.

From the docs:

// Timeout if a server does not return a response in 3.14 seconds.
$client->get('/delay/5', ['timeout' => 3.14]);
// PHP Fatal error:  Uncaught exception 'GuzzleHttp\Exception\RequestException'

The RequestException has the info in itsmessage property:

"cURL error 28: Operation timed out after 3114 milliseconds with 0 bytes received"

So I could evaluate the message pattern but this feels kinda wrong, because those messages could easily be changed in the future.

Is there a better/more stable way to check for timeouts when using guzzle 4?