ress Book is next launched or another message arrives for it.</P>
<P>
When the user gives the go-ahead for delivering the message, the application is notified, via IACP. When the application has acknowledged receipt of the message, the descriptor is removed from the inbox (though not from the file).</P>
<P>
The application will call the Mailbox library to obtain the data format of the message body. If it can accept that format, the application will call the library again, telling it to ask the data driver f