Support for Automatic Transaction Initiation (ATI)

Client applications can control whether ATI transactions are allowed by using the setATI() and queryATI() methods on the CclTerminal class.

The default setting is for ATIs to be disabled. The following code fragment shows how to enabled ATIs for a particular terminal:

// Create terminal connection to CICS server 
CclTerminal terminal( "myserver" ); 
// Enable ATIs 
terminal.setATI(CclTerminal::enabled);

The CclTerminal class performs one or more of the following

Run any outstanding ATIs as soon as a transaction ends
Call additional programming needed to handle the ATI replies
Run ATIs before or between client-initiated transactions

depending on whether the call synchronization type is Synchronous, Asynchronous or Deferred synchronous.

Synchronous: When you call the CclTerminal send() method, any outstanding ATIs will be run after the client-initiated transaction has completed. The CclTerminal class will wait for the ATI replies then update the CclScreen contents as part of the synchronous send() call. If you expect an ATI to occur before or between client-initiated transactions, you can call the CclTerminal receiveATI() method to wait synchronously for the ATI.
Asynchronous: When the client application calls the CclTerminal send() method for an async session, the CclTerminal class starts a separate thread to handle replies. If ATIs are disabled, this thread finishes when the CICS® transaction is complete. If ATIs are enabled, the reply thread continues to run between transactions. When the CclTerminal state becomes idle, any outstanding ATIs are run and ATIs received subsequently are run immediately. The reply thread is not started until the first CclTerminal::send() call, so if you expect ATIs to occur before any client-initiated transactions, you can call the receiveATI() method to start the reply thread.
Deferred synchronous: After the CclTerminal send() method is called for a dsync session, the poll() method is used to receive the replies. Outstanding ATIs are started when the last reply has been received (that is, on the final poll() call). You can also call the poll() method to start and receive replies for ATIs between client-initiated transactions. As the poll() method can be called before or between client-initiated transactions, the receiveATI() method is not needed (and is invalid) for deferred synchronous sessions. For any of the synchronization types you can provide a handleReply() method by subclassing the CclSession class. As for client-initiated transactions, this method will be called when the ATI 3270 data has been received and the CclScreen object updated. The transID() method on the CclTerminal or CclSession can be called to identify the ATI.