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:
Feb. 18, 2003
Filed:
Jul. 13, 2000
Robert Douglas Holt, Rochester, MN (US);
Thomas M. McBride, Mantorville, MN (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
An apparatus and method provide a locking scheme that accommodates different size file locks. A first file lock command, referred to as an M bit file lock command, assumes a lock with a length of M bits. A second lock command, referred to as an N bit file lock command, assumes a lock with a length of N bits, which is less than M bits. A translation mechanism services both M-bit and N-bit file lock commands, and accesses locks that are M bits in length in response to both M-bit and N-bit file lock commands. The address range between 2 and 2 −1 are assigned to one or more corresponding control addresses in the address range of 0 to 2 −1. Locking of any control address using an N bit file lock command results in the address range between 2 and 2 −1 being automatically locked in addition to the addresses specified in the N bit file lock command. This allows translating an N bit file lock command to an M bit lock. Similarly, when an M bit file lock command locks any address between 2 and 2 −1, the translation mechanism locks the address or addresses specified in the M bit file lock command, and in addition locks the control address or addresses that correspond to the specified address. In this manner, both N bit and M bit file lock commands may access the same M bit locks, assuring that proper locking is maintained between computer programs that use N bit locks and computer programs that use M bit locks.