Patents by Inventor Craig E. Hatfield

Craig E. Hatfield has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5522029
    Abstract: A rendezvous technique makes use of a semaphore that operates independently of its initial value. All participating programs (or processors) write this semaphore before reading it; therefore, the semaphore is reinitialized as it is used regardless of which program accesses it first. Initialization with use allows this semaphore to be used at any time without regard to previous use or data corruption. One master program initializes the semaphore's data and then sets a flag indicating the data's validity. The master program then continues to set the valid flag until the data shows the rendezvous' completion. The other participating programs first set the semaphore valid flag to invalid (before or after the master program sets it) and wait until the flag transitions from invalid to valid. At that time they will atomically manipulate the data. After each program has modified the semaphore's data, it indicates the completion of the rendezvous.
    Type: Grant
    Filed: May 9, 1995
    Date of Patent: May 28, 1996
    Assignee: International Business Machines Corporation
    Inventor: Craig E. Hatfield