About the Sample Transport Provider

About the Sample Transport Provider

A transport provider is a dynamic-link library (DLL) which acts as an intermediary between the MAPI subsystem and one or more underlying messaging systems. All transport providers support a range of standard features, such as the following:

  • Providing proper security for the underlying messaging system.
  • Sending and receiving messages from the underlying messaging system.
  • Exposing the address types the transport providers support so MAPI and client applications can use them appropriately.
  • Accepting delivery for specific recipients.

The Sample Transport Provider implements these features by using a shared network file system. This is a messaging system where the transport provider writes messages directly to the shared folder.

A transport provider DLL must conform to the interface specified by MAPI. As a transport provider developer, you implement this interface in terms of the functionality present in the messaging system.

The Sample Transport Provider

To step through the sections of a transport provider DLL, you can download and install a Sample Transport Provider. For more information, see Installing the Sample Transport Provider. This Sample Transport Provider, named MRXP, implements a shared network file system transport provider. The sample code can be used as a starting point for building a more robust transport provider.

In This Section

Installing the Sample Transport Provider

Explains how to download, install, and use the Sample Transport Provider.

Initializing a Transport Provider

The first step in implementing a transport provider is initializing the transport provider so that MAPI can log on to the transport provider.

Setting Up a Transport Provider

After the transport provider is initialized, you must set up the transport provider so MAPI can determine what e-mail address types the transport provider accepts. When the transport provider is ready, it calls the TransportNotify function to enable message transmission.

Sending Messages by Using a Transport Provider

After message transmission is enabled, you can send messages by using the transport provider. The transport provider calls the SubmitMessage function when it has a message waiting to be sent.

Receiving Messages by Using a Transport Provider

After message transmission is enabled, you can receive messages by using the transport provider. The transport provider calls the Poll function to indicate that there are messages waiting to be received.

Shutting Down a Transport Provider

After you are finished using a transport provider, you must shut down the transport provider properly by calling the TransportLogoff function.

See Also

Developing a Transport Provider

Transport Provider's Role in the MAPI Subsystem