title: How to use OpenID without asking user for his OpenID URL?
body: <p>I'm setting up an OpenID provider using DotNetOpenAuth and I'm stuck.</p>
  
  <p>It seems that OpenID requires that the user provides his OpenID URL first, and then the consumer would redirect him to the provider, giving the URL as a parameter (checkid_setup mode).</p>
  
  <p>But with google, and some other providers, it works differently. You are just redirected to a generic page where you would either sign in, or select one of the accounts you're already logged in with. Or just redirected back if you're logged in with a single account.</p>
  
  <p>Is this somehow related to the checkid_immediate mode? If so, please give me a link to an article explaining how that works.</p>