CWA 16926-3:2022

Extensions for Financial Services (XFS) interface specification Release 3.50 - Part 3: Printer and Scanning Device Class Interface - Programmer's Reference

Scope

This specification describes the functionality of the services provided by banking printers and scanning devices under XFS, focusing on the following areas:
• application programming for printing
• print document definition
• integration with the Windows architecture
• scanning images for devices such as check scanners
These descriptions include definitions of the service-specific commands that can be issued, using the WFSAsyncExecute, WFSExecute, WFSGetInfo and WFSAsyncGetInfo functions.
The requirements for printing in banking applications are significantly different from those of the conventional PC environment, and the XFS support delivers the foundation for financial application printing, including:
• Controlled access to shared printers
The banking printers can be shared between workstations and the XFS layer provides the ability for the application to manage ownership of a print device. This allows an application to identify the operator granted control of the printer, and to ensure that a teller printing multiple documents is not interrupted by work for other applications.
• Application controlled printing
In the banking environment, it is necessary for the application to receive positive feedback on the availability of print devices, and the success or failure of individual print operations. The XFS printer support provides a standard mechanism for application retrieval of this status information.
• Management of printing peripherals
Distributed banking networks require the ability to track the availability and failure of printing peripherals on a branch and system-wide basis. Through the XFS WFSRegister function monitoring programs can collect error alerts from the banking printers.
• Vendor independent API and document definition
All of the XFS peripheral implementations are designed around a standardized family of APIs to allow application code portability across vendor hardware platforms. With printers, it is also recognized that banks invest a significant amount of resource in the authoring of print documents. The XFS printer service class is implemented around a forms model which also standardizes the basic document definition. This extends the investment protection provided by XFS compliant systems to include this additional part of the application development.
- Windows printing integration
It is possible for a banking printer to offer printing capabilities that can be accessed by non-banking specific applications, such as general office productivity packages. This would not, for example, be true for a receipt printer, but it could be the case for a device with document printing capabilities. A vendor may choose an XFS implementation that allows both types of applications (XFS and Windows applications using the Windows printing subsystem) to share the printing devices. The vendor should specify any impact this approach has on XFS subsystem operation, such as error reporting.
Full implementation of the above features depends on the individual vendor-supplied Service Providers. This specification outlines the functionality and requirements for applications using the XFS printer and scanning services, and for the development of those services.