Abstract: Methods and systems are provided for implementing partition manipulation tools. One embodiment of a partition manipulation computer system implements an architecture that supports multiple file systems on a computer. The computer system includes a data replicator for replicating data from a selected partition to a modified partition in a partitionable storage medium. The data replicator has an initialization interface for interfacing to initialization modules in a format that is substantially independent of each file system used on the computer system. The initialization modules, which may be specific to one or more file systems, generate sector identifications. A verification interface and a completion interface are also provided, for interfacing with file-system-specific verification and completion modules.

Abstract: A system and method separate the order in which event handlers register from the order in which the event handlers are notified of events. This allows any convenient registration order to be used together with a notification order that corresponds to a network architecture, a memory hierarchy, or another familiar scale. The notification order is determined by the event producers, and therefore may be reversed without re-registering the event handlers. Events may be broadcast, may carry data between event handlers, and may be consumed to prevent further notifications.

Abstract: Methods and systems are provided for synchronizing local copies of a distributed database, such as a master copy and a partial copy stored in a replica or in a cache. Each data item in the database has an associated timestamp or other tag. An index into the tags in maintained. The tag index may be used to create an event list to reduce the time and bandwidth needed to synchronize the local copies. The tag index may also be used to create a virtual update log, thereby removing the need to maintain one or more physical logs recording the history of the copies.

Abstract: A method and system are provided for managing digital documents by using links to allow navigation between documents and to create associations based on bridges between various combinations of document elements and software. Each bridge includes at least one coupling. Each coupling includes a target token identifier and a supplementary token identifier which allow software users to navigate between target and supplementary documents or to invoke supplementary software routines. Linked elements, such as text or graphics tokens, can overlap partially or entirely. Embedded links are allowed, but are not required.

Abstract: Methods and systems are provided which make security, licensing, and browsing capabilities of directory services available for use with the Java language and environment, and thus provide an alternative to security restrictions imposed on Java applets. A Java component type is created in a directory services schema. The Java component type specifies where a Java class can be found in a LAN or on the Internet. The key attributes of the Java component type are its common name (specifying a Java class) and either a reference to the file containing the Java class's byte codes or a binary stream attribute containing the byte codes. The loadClass( ) method is extended to look for Java classes within a directory services database. The directory services features thus made available include support for securing, metering, and licensing individual Java classes.

Abstract: Methods and systems are provided for controlling access to objects in a hierarchical database. The database may include a directory services repository, and/or synchronized partitions. An access constraint propagator reads an access control property of an ancestor of a target object. The access control property designates an inheritable access constraint such as an object class filter or an "inheritable" flag. The object class filter restricts a grant of rights to objects of an identified class. The "inheritable" flag allows inheritance of an access constraint on a specific object property. The propagator enforces the inheritable access constraint by applying it to at least the target object.

Abstract: A method and apparatus for management of application programs in a computer network are disclosed. A modified hierarchical database which includes application objects that represent applications and their execution environments is utilized. Administrator tools support the creation, deletion, and modification of application objects. Each application object includes the location of an executable code for a given application, an icon, a working directory name, drive mappings, printer port captures, command line parameters, and similar information. An application launcher queries the database and updates a list of available applications which is kept in the user's desktop. The launcher automatically launches specified applications when a user runs the launcher. The launcher also uses the information in the application object to setup resources needed by the application, to create a process that executes the application, and to clean up after the application terminates.

Abstract: Methods and systems for managing replicated objects in a partitioned hierarchical database are disclosed. One method combines partition-wide object identifiers in order according to ancestry to form a database-wide object identifier that identifies a target object relative to all other objects in the database. Each partition-wide object identifier includes a replica identifier and at least one integer value. Suitable integer values include timestamp values, event counter values, random values, and GUID values. Other methods use the identifiers to access objects after a single object or a subtree of objects has been renamed or moved.

Abstract: A method and apparatus are disclosed for controlling collaborative access to a work group document by the users of a computer system. A combination of public-key cryptographic methods, symmetric cryptographic methods, and message digest generation methods are used. The document has a data portion and a prefix portion. A computer-implemented collaborative encryption method uses structures in the prefix portion to restrict access to the information stored in the data portion. Users who are currently members of a collaborative group can readily access the information, while users who are not currently members of the group cannot. Other structures in the prefix portion support collaborative signatures, such that members of the group can digitally sign a particular version of the data portion. These collaborative signatures can then be used to identify the signing member and to determine if changes in the data portion were made after the collaborative signature was linked to the document.

Abstract: A method and apparatus for combining writes and avoiding redundant writes are disclosed. Based on values such as overhead message size, largest message size, packet round trip time, cache block size, dirty cache region size and separation, channel throughput, and the identity of cached data values, a write region containing cached data is selected and (if non-empty) is written across the network. Depending on conditions, the selected write region includes either two dirty regions and an intervening clean region or only one dirty region. In the latter case, the other dirty region is flushed by a subsequent write operation. The goals of avoiding network congestion, updating the cache promptly, and utilizing available network bandwidth are balanced according to conditions in the cache and on the network.

Abstract: A method and apparatus are disclosed for managing software components in a network of computers such as a local area network or the Internet. Each software component includes a binary object and at least one interface to the binary object. Suitable software components include OLE components. The network includes a registry file identifying currently registered components and their locations. The network also includes a component server computer on which unregistered components reside. A database associates software component identifiers with software component locators. Suitable databases include Novell NetWare Directory Services databases and Internet search engine databases. Database objects or entries representing unregistered components are found by a search based on the class identifier of a desired component. Software components found by the search are selected, transferred as needed, and then registered, thereby making them available to clients.

Abstract: A method allows non-destructive manipulation of disk partitions defined by an IBM-compatible partition table. The disk partitions may be located on one or more disks attached to one or more disk drives. Each partition has an associated file system type. An interrupted manipulation may be resumed at a point in the progress of the manipulation near the point of interruption. Available manipulations include verifying the integrity of a partition's file system structures; displaying information about a partition; moving a partition to a different location; resizing a partition; and resizing the file system clusters. The resizing steps are illustrated with particular reference to file systems which use a file allocation table. The details required to perform these manipulations are attended to by an implementing program that requires only general direction from a user.

Abstract: A method allows manipulation of disk partitions defined by an IBM-compatible partition table. The disk partitions may be located on one or more disks attached to one or more disk drives. Each partition has an associated file system type, such as FAT or HPFS. An interrupted manipulation may be resumed at a point in the progress of the manipulation near the point of interruption. Available manipulations include verifying the integrity of a partition's file system structures; displaying information about a partition; moving a partition to a different location; resizing a partition; and converting a partition from one file system to another file system. The resizing step is illustrated with particular reference to HPFS file systems and FAT file systems. The details required to perform these manipulations are attended to by an implementing program that requires only general direction from a user.

Abstract: A computer system having data organized in files, having a secondary storage for storing files, having a primary storage, and having one or more types of file subsystems (file system implementations) for controlling transfer of files between primary storage and secondary storage. A subset of writes to secondary storage are performed using a Delayed Ordered Write (DOW) subsystem, which makes it possible for any file system to control the order in which modifications are propagated to disk. The DOW subsystem consists of two parts. The first part is a specification interface, which a file system implementation or any other kernel subsystem can use to indicate sequential ordering between a modification and some other modification of file system structural data. The second part of DOW subsystem is a mechanism that ensures that the disk write operations are indeed performed in accordance with the order store.

Abstract: Techniques used in a virtual memory system for mapping the page table for a process onto the process's virtual address space. The mappings make it possible for the virtual memory manager to compute addresses for the page table in the same fashion, regardless of the page table configuration required by the hardware. The techniques include linear mapping of a process's page table entries onto a portion of its virtual address space and self-recursive mapping of page trees onto the virtual address space. The techniques make porting an operating system to various kinds of hardware easier, reduce the size of the portion of virtual memory which must be reserved for the page table, and speed up references to the page table by the virtual memory manager. Further refinements permit creation of nodes of the mapped page table on demand and access of a second process's page table from a first process's page table.

Abstract: A method and apparatus for assisting in file recovery after a network fault uses a block state indicator in a client cache. After file data is stored in the client cache, the block state indicator is set to a client-cached state. After the file data is stored in a server cache, the block state indicator is set to a server-cached state. After the file data is stored in a non-volatile store attached to the server, the block state indicator is set to a stored state. If the data in server cache is lost or compromised due to a network fault, the data maintained in client memory is retransmitted. In a similar manner, file locks and file semaphores are re-established after a network fault.