Abstract: A method for maintaining an alterable document history log in a data processing system having multiple resource objects which are accessible by a plurality of users within the data processing system. A history log is created and associated with each resource object for which documentation of selected activities is desired. A list of one or more specified types of activities is generated and utilized to filter all activities which take place with respect to a particular resource object in order that the occurrence of selected activities may be documented. A characterization of these activity types is recorded in association with the document history log such that subsequent users may ascertain what types of activity occurrences have been recorded. In the depicted embodiment of the present invention access to a resource object may be locked and the list of specified types of activity altered.

Abstract: An interface circuit board connected to a VMEbus standard backplane bus of a first data processing system, and also to a Futurebus standard backplane bus of a second data processing system, provides address/data conversion and interrupt service between the two standard bus structures. The Futurebus, being a higher level bus than the VMEbus, has no provision for hardware interrupts; event related data are conventionally transmitted across the Futurebus like any other data item. The interface board signals VMEbus interrupts to Futurebus devices by way of the Futurebus bus arbitration facility. Interrupts generated on the interface circuit board and interrupts from the VMEbus priority interrupt bus are mapped and converted into message numbers, one of which is asserted on the Futurebus arbitration bus as an arbitration number higher than the arbitration numbers assigned to Futurebus devices.

Abstract: A data transfer network for computers is disclosed which combines characteristics of both multi-port memory devices and local area networks. Each computer is coupled to the network via a data terminal. The terminal permits the network to appear to the computers as random access memory. Data written into this RAM by the computers is formatted by the terminals into serial data packets, which are shifted around a serially connected ring or loop of the terminals. The loop connected terminals form the network.

Abstract: The present invention is a system and method which follows a directory tree of a random access disk 20 to obtain file location information and the contents for multiple files. For each file found an entry is created on a file description ring 90 and the file location information is stored in the entry. An insert pointer indicates the next available entry on the ring 90. The system then stores the different type location information (for example file headers, directories and directory headers are different types) for each of the files in corresponding segmented ring buffers 172, 176 and 192 dedicated to storing information of only a single type. The file content is also stored in a dedicated segmented file content ring buffer 132. Each time a ring is updated with information for a file, a corresponding operation pointer (96, 100 and 102) for the ring 90 is advanced.