Offers

This topic applies to Windows XP Home Edition and Windows XP Professional only.

An offer is a way for the user to pay for a service in advance. An offer contains a description of the service and the period of time when the offer is available.

DirectShow implements a generic offer object. A policy creates an instance of this object, sets the description and availability properties, and adds one or more tolls. To purchase the offer, the user pays one of the tolls. The policy stores a record of the payment.

At the scheduled time, the user will submit a request for the service to Video Control. When the policy receives the request, it looks up the toll, determines that the user has already purchased the service, and refrains from imposing any denials.

Purchasing an offer from one policy does not prevent other policies from blocking the same request. Otherwise, offers would provide a way to circumvent legitimate policies. For example, you cannot override a parental policy by purchasing a pay-per-view program in advance. If there is a conflict, the policy that issued the offer should provide a refund.