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:
Oct. 10, 1995
Filed:
Jun. 10, 1994
Kenneth L Thompson, Watchung, NJ (US);
AT&T IPM Corp., Coral Gables, FL (US);
Abstract
A file system which has component file systems including a primary file system which is react/write and a number of dump file systems which are read only. Each dump file system is created from the primary file system by means of a dump operation and conserves the state of the primary file system at the time the dump operation was performed. Component file systems share read only storage elements with older component file systems. The file system is implemented on a system including a file server, a magnetic disk mass storage device, and an optical write once-read many (WORM) disk. The magnetic disk mass storage device contains the read/write storage elements of the primary file system and encached read only storage elements from the WORM disk. Space is reserved on the unwritten portion of the WORM disk for the read-write storage elements of the primary file system. Techniques for performing file operations including opening, reading, writing, creating, and deleting files are disclosed, as well as techniques for performing the operations of dumping and restoring the primary file system.