Browse Prior Art Database

METHOD for the RECOVERY of COMPOSITE DOCUMENTS in DISPLAYWRITE 4

IP.com Disclosure Number: IPCOM000040713D
Original Publication Date: 1987-Dec-01
Included in the Prior Art Database: 2005-Feb-02
Document File: 5 page(s) / 66K

Publishing Venue

IBM

Related People

Gentry, AV: AUTHOR [+6]

Abstract

A method is described to permit DisplayWrite* 4 (DW4) users to repair the Two-level Index structure, Data content (Text) and Non-text Object data within DW4 Composite documents. Recovery allows the user to be capable of editing Composite documents that otherwise would be useless due to a damaged index structure and/or datastream content errors or non-text object errors. (Image Omitted) DisplayWrite 2.0 - 3.1 supports recovery of the Two-level Index structure and Datastream content of a Text document. The Recover Document function selectable from the Document Utilities Task Selection menu allows DW2 - DW3 users to recover their Text documents. On DisplayWrite 4.0, the concept of a 'Non-text Object' data structure was introduced.

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METHOD for the RECOVERY of COMPOSITE DOCUMENTS in DISPLAYWRITE 4

A method is described to permit DisplayWrite* 4 (DW4) users to repair the Two-level Index structure, Data content (Text) and Non-text Object data within DW4 Composite documents. Recovery allows the user to be capable of editing Composite documents that otherwise would be useless due to a damaged index structure and/or datastream content errors or non-text object errors.

(Image Omitted)

DisplayWrite 2.0 - 3.1 supports recovery of the

Two-level Index structure and Datastream content of a Text document. The Recover Document function selectable from the Document Utilities Task Selection menu allows DW2 - DW3 users to recover their Text documents. On DisplayWrite 4.0, the concept of a 'Non-text Object' data structure was introduced. A non-text Object is a data construct consisting of a finite data byte count in a predefined format. Additionally, DW4 introduced the concept of a 'Composite document.' A Composite document is a data construct consisting of logical records and a finite number of non-text objects.

(Image Omitted)

In accordance with the new method, DW4 also provides support to recover non-text objects as well as the Index structure and datastream content which was customary on DW2 - DW3. DisplayWrite
4.0 users therefore have the capability to perform the following non-text object recover operations within a Composite document: 1. Recovery of a non-text object within a Composite document that

does not have a control reference

2. Recovery of a non-text object that does not exist within a

Composite document, but has a control reference

3. Recovery of a non-text object within a Composite document

whose object type is not supported by DisplayWrite 4.0

4. Recovery of a non-text object within a Composite document

whose data content is damaged

5. Recovery of all non-text objects within a Composite document

in a single operation

6. Recovery of the Two-level Index, Datastream content and all

non-text objects in a single operation

7. Recovery of only the Two-level Index structure and Datastream

content in the absence of any non-text objects

The Recovery is performed in (4) primary steps:

1. Recovery of the Two-level Index structure

* Text Record

* Non-Text Object

2. Recovery of the Datastream contents

1

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3. Recovery of Non-existent Non-Text Objects

4. Recovery of Unreferenced Non-Text Objects Upon completion of the recover document process, any damage to the Two-level Index structure of Datastream contents and Non-Text objects references and index errors will be repaired/corrected. Consequently, DisplayWrite
4.0 users can again successfully edit their Composite documents.

Two-level Index Recovery Text Records Recovery During the Recovery process all records which have names will have their names reset to the "unnamed record value." The unnamed record value is used as the name for records which logically fit on the same page in the Composite document. The actual...