Modes

Abstract: A computer system having a facility for concurrently sharing objects or resources is described. The system includes a publish-and-subscribe facility or "Object Exchange," for facilitating sharing among workgroups. When a data object is "published" by a user ("publisher"), the object is sent from that user's computer to other computer users specified by the publisher. Those interested in the published data object (published pages) may elect to receive or "subscribe" to that data. From that point on, the publisher can choose to update the data, such as whenever the published version changes. The "subscribers" of the published pages automatically get updates. Subscribers of a spreadsheet notebook, for instance, would automatically receive pages as they are published. The Object Manager effects actions by posting messages or "forms" to either the local Object Exchange (assuming one is the publisher) or the Object Exchange of others (subscribers). Connectivity for the system is provided by the various Object Exchange engines negotiating forms. Each Object Exchange posts and retrieves forms at polling intervals (which may be set to continuous polling). By exploiting the connectivity of existing transport media (e.g., LANs), the present invention delivers workgroup computing benefits to users, but without imposing a rigid structure which restricts when and how they work.

Abstract: A parallel virtual file system for parallel processing systems including single-processor systems having multiple storage devices. The invention manages partitioned files as follows: (1) partitions of a partitioned file are stored in a set of isomorphic "data trees"; (2) an additional directory tree, called the "control tree", is used to build a model of the intended structure of the data trees; (3) the combination of a control tree and a collection of data trees is referred to as a "multifile system", with sets of files referred to as "multifile" and sets of directories referred to as "multi-directories;" data elements of a multifile or multidirectory are referred to as "data plies" and control elements of a multifile or multidirectory are referred to as "control plies"; (4) a set of multifile subroutines is provided for accessing and modifying the multifile system in such a way so as to preserve the isomorphic data structures for the partitioned data; (5) the multifile subroutines use a distributed computing environment which provides for remote procedure calls and, in one of the embodiments of the invention, for a distributed transaction processing protocol to ensure atomicity of structural changes to the multifile system; (6) interference of concurrent file system operations is prevented by creating a "transactional" lock for each file system.

Abstract: A method to access appropriate versions of files or objects in a computer with a graphical user interface. The invention creates a container "movie" object which "contains" a user or program selected group of contained objects--which are typically versions of a file, data at different stages in processing or any other set of files which are temporally related. Since such temporally related objects are usually accessed "one at a time", the container displays within itself an icon for only one of the contained objects--typically the most recent or currently active file. The other non-active versions are kept hidden, to prevent accidental access and reduce visual clutter. To access any of these hidden versions, a method is disclosed which forces the user to "rewind" or "forward" in a movie like fashion to the past or recent versions with an animation rate indicative of the date proximities between adjacent versions--thereby giving the user a "feel" for recency or newness. The user may change the active version during animation using a keystroke or pointing action. The major new effect of the present method is that when a plurality of movie icons are browsed the computing environment or file system can be made partially reversible, assisting users to revert back and allowing programs to access older files or drivers which were known to be stable.

Abstract: The present invention is a system and method for "checking the use of synchronization locks in a multi-threaded computer program" (hereinafter "WARLOCK II"). In Warlock II a set of source code representing a process which includes multiple threads may be annotated by the developer using a "NOTE" macro to describe the desired operation of the locks. This annotated source code is passed to a modified ANSI C compiler which outputs a special file designated a ".ll" file, as for example, file "foo.ll". This special ".ll" file is then processed as input along with other designated ".ll" files which might be related, by a "wlanalyze" program which will check the source code of the target programs in the ".ll" files to determine whether their use of synchronization locks is consistent with the intended use as specified in the annotations.