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:
Jun. 02, 1998
Filed:
Jan. 03, 1996
Steven T Senator, Colorado Springs, CO (US);
Billy J Fuller, Colorado Springs, CO (US);
Sun Microsystems, Inc., Palo Alto, CA (US);
Abstract
Various versions of a computer file are provided without requiring copying the file or logging changed data, so that the files have consistent user data. A program module responds to a system call argument and allocates another node in file system tables and copies metadata information from the old node into the new node, so that both nodes contain the same data block allocation information. Portions of the module set shadow pointers in the old node to point to the new node, and in the new node to point to the old node. Changes to data are made with respect to the new node and fresh physical data blocks are allocated for the changed blocks. A method includes the steps of allocating a new node for storing file allocation information for another version of an existing file; logically connecting the new node to the existing node for file name and other purposes; and replacing node identification information in the directory with the new mode identification. In other steps the method replaces the current node identification information of a file in the directory with previous node identification information obtained from the current node; and logically disconnects the current node from the previous node.