Building Distributed
Applications
Using the Progress AppServer
Managing Asynchronous Requests
Asynchronous requests allow a 4GL client to execute a remote procedure and continue execution before the AppServer has completed (or even begun) executing the remote request. This mechanism enhances client performance, especially in an event-driven application where the user can continue interacting with the client application while the AppServer processes the remote request.
In the following sections, when executing an asynchronous request, Progress places the request on a send queue for the connection until the AppServer can execute the specified remote procedure. Similarly, when the procedure completes execution, Progress places the results on a response queue, where the results wait until the client handles the PROCEDURE-COMPLETE event associated with the request. As a result, all asynchronous requests on a connection are guaranteed to be executed, with results returned, in the order you submit them. For more information on the send and response queues, see Overview of the Progress AppServer."
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