analogWrite freeze the arduino

Yes i use the ethernet shield, Don't know how to extract the rgb value without using the string, cause when the server receive a data, it look like
(get/ 255,255,255 / HTTP1.1) So could you point me on how to extrat 255,255,255 and put them individually to r = 255 g = 255 b = 255 without using string.

Thanks again