The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 11, 1992
Filed:
Apr. 25, 1990
Frederick C Kruesi, Exton, PA (US);
David W Heileman, Jr, West Chester, PA (US);
Unisys Corporation, Blue Bell, PA (US);
Abstract
Message Segments comprising Messages are stored in a flat file on disk. A unique Message Number is assigned to each Message and each Message Segment is stored at a flat file address (Segment Descriptor) in a record containing the Message Segment data and recovery information. the Recovery Information includes fields for an Available Marker, Message Number, Segment Sequence Number, Final Flag and Last Address. The Available Marker denotes whether the Message Segment is in-use or available. The Message Number field contains the Message Number identifying the Message which contains the Segment. The Segment Sequence Number donotes the order in a Message occupied by the Segment. The Final Flag field contains a flag if the Messge Segment is the Last Segment of the Message. The Last Address field contains the Segment Descriptor of the Last Message Segment of the Message containing the Segment. A data base for accessing the Message Segments is maintained on disk. Each data base record contains the Message Number identifying the Message and the Segment Descriptors of the Message Segments comprising the Message. Recovery and rebuilding of the data base from the Recovery Information in the flat file is performed if the data base inconsistency is detected. Comparisons of the Message Numbers in the data base and Recovery Information and testing the Availability Marker provide indicia for initiating recovery of the data base from the Recovery Information.