Using specialized output device job spooler as generic buffer manager

摘要

In a user interactive multitasking data processing system, a comprehensive managing subsystem is constructed for managing queued processing of tasks of a particular type that ordinarily are not handled on a queued basis by the associated operating system. The subsystem is constructed around a task control utility which lacks capability for controlling required display presentation and queue managing functions for the respective task type. The utility is adapted to interface with operating system elements that ordinarily perform display and queue management functions relative to tasks other than the tasks handled by the utility. In the embodiment specifically disclosed, a utility for managing queued processing of page image data (e.g. data produced by document scanners or other image capture devices) interfaces with Presentation Manager and Print Spooler elements of the OS/2 TM Operating System. The utility per se lacks functional capabilities for display and queue management, which are required for managing the processing of associated image data, and therefore requires considerably less storage capacity than it would need if such capabilities were included. These functions are performed by the OS/2 elements to which the utility interfaces. However, the utility accesses image data in the queues created by the OS/2 Spooler transparent to (i.e. without cooperation of) the Spooler, when transferring such data between the queues and associated processing applications. Thus, the utility operates more efficiently than it would if required to invoke the Spooler when making such transfers.