Patent · US Expired

Incorporation of services written in one operating system environment into another operating system environment

US5715458A · kind A · utility

10Cited by
15References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 13, 1995
Grant dateFeb 3, 1998
Priority date
Expiry dateFeb 13, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/45537
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Data processing apparatus comprises a processor and memory. The processor has a supervisor state including a first set of supervisor service routines for controlling the operation of the data processing apparatus. The memory has a first hash table accessible by the supervisor state for pointing to the first set of supervisor service routines and a second hash table also accessible by the supervisor state for pointing to a second set of supervisor service routines. The data processing apparatus provides table indicating means for indicating whether the first hash table or the second hash table is accessible by the supervisor state. The table indicating means is provided as an index into the first hash table. When this index is accessed, further code is executed which allows access to the second hash table. The operation of the data processing apparatus is controlled by a routine comprising the steps of testing to determine which hash table is to be used for calling the routine, using the determined hash table to find the address in the memory at which the code representing the called routine is resident, and executing the routine in the processor. In one embodiment of the invention,…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.