| Platform SDK: SMTP Server Events |
[This is preliminary documentation and subject to change.]
This section lists the IMailMsgNotify interface used by transport event sinks and store driver components to notify callers that asynchronous processing has completed. In all cases, passing a NULL value for a parameter marked as a reference of type IMailMsgNotify causes the method to run synchronously (i.e. the method does not return until processing has completed). Methods that support asynchronous execution may still complete synchronously; callers must check the returned HRESULT value. If the value is MAILMSG_S_PENDING, the method is running asynchronously, and the caller will be notified when processing completes through the passed object reference's Notify method. If the method returns S_OK, the operation has completed synchronously and no callback will be received.