Using the DirectX Protocol in an Application

This section covers how you can use the features of the Microsoft® DirectPlay® protocol in your application.

You can use five DirectPlay interfaces to send messages.

• IDirectPlay8Peer
• IDirectPlay8Client
• IDirectPlay8Server
• IDirectPlay8LobbyClient
• IDirectPlay8LobbiedApplication

Depending on which interface your application is using to send messages, you send a message by calling a method named either Send, or SendTo. While the usage of these five methods is similar, they vary in detail. Refer to the appropriate reference pages for further discussion.

The Send/Sendto method's parameters might allow you to control many of the DirectPlay protocol's features. For example, the dwFlags field of IDirectPlay8Peer::SendTo allows you to specify:

• The message's priority level.
• Whether the message is reliable or unreliable.
• Whether the message is sequential or non-sequential.

Refer to the appropriate method reference for further details.

When your application receives a message, your callback function will receive a DPN_MSGID_RECEIVE message. The associated structure contains a pointer to the data block, along with information such as the source of the message.