How can I get facebook to prompt for authorization for my app every time?

I'm writing an app that will allow a user to log in to multiple facebook accounts. Basically I'm just going to store the authorization token for each account and use them as needed, so the authorization is just to get that token, not to actually log the user into facebook. As such, I want the user to have to enter their credentials every time, even if they're currently logged in to facebook. I authenticate the accounts like this:

https://graph.facebook.com/oauth/authorize?
    client_id=...&
    redirect_uri=http://www.example.com/oauth_red开发者_开发问答irect

How can I tell facebook to authenticate every time? I'd also like to remove the "remember me" option, so that they aren't logging into the browser with the account that they enter here.

There is a parameter that you can pass to force authentication: auth_type=reauthenticate. For example: http://graph.facebook.com/oauth/authorize?client_id=184484190795&redirect_uri=https%3A%2F%2Fwww.fbrell.com%2Fecho&auth_type=reauthenticate.

Edit: There is documentation for this here: https://developers.facebook.com/docs/reauthentication/.

You can logout the user using FB.logout: https://developers.facebook.com/docs/reference/javascript/FB.logout/

Caveat: it is against Facebook policy for users to have more than one profile.