Programmers who are familiar with IBM i programming are accustomed to using queues. Data queues simply represent a method that is used to pass information to another program.
Because this interface does not require communications programming, you can use it either for synchronous or for asynchronous (disconnected) processing.
You can develop host applications and PC applications by using any supported language. For example, a host application might use RPG, and a PC application might use C++. The queue is there to obtain input from one side and to pass input to the other.
The following example shows how data queues might be used, as shown
- A PC user might take telephone orders all day, and enter each order into a program, and the program places each request on an IBM i data queue.
- A partner program (either a PC program or an IBM i program) monitors the data queue and pulls information from queue. This partner program can be simultaneously running, or started after peak user hours.
- It might or might not return input to the initiating PC program, or it might place something on the queue for another PC or IBM i program.
- Eventually, the order is filled, the customer is billed, the inventory records are updated, and information is placed on the queue for the PC application to direct a PC user to call the customer with an expected ship date and print the order.
