Abstract: A plurality of host processors share access to a peripheral data storage subsystem and each have program means for controlling asynchronous operations of the subsystem. Control blocks in each of the host processors are addressably linked together for enabling inferred access to a unit control block (UCB) for any of a plurality of peripheral devices in the subsystem. The subsystem selectively groups some of the devices such that only devices designated as primary devices are addressably accessible by host processor application programs. Other devices in the respective groups are secondary devices and are accessed by the subsystem whenever the primary devices in the same group cannot perform a host processor commanded operation. Means are provided for identifying the secondary devices to all of the host processors.

Abstract: A large plurality of electronically-stored fonts are managed and selected for use in a particular presentation (printing, display) of a document represented by electrical signals by either an explicit or implicit method. A new font by either selecting a completely defined font or by selecting predetermined characteristics of font graphics, such as italics, bold, point size, and the like which enable an implicit selection of a completely defined font. Such defined characteristics are interpreted by an automatic machine to complete font definitions for use by a document presentation device. A begin font command can specify a plurality of internal fonts with the order of specification indicating priority of selection for use in document presentation. Whether or not a specified internal font results in a defined font being activated is selectable by font definitions embedded with a received-text-data stream representing text/graphics to be presented.