Virtual machine system for accessing external subprogram functions
US6141723A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 7, 1998 |
| Grant date | Oct 31, 2000 |
| Priority date | — |
| Expiry date | Apr 7, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F12/0638
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A virtual machine system for accessing program functions. The system couples ROM memory to RAM memory in a manner which allows the memory to be independently removed and updated. A virtual machine and class module are stored in the ROM memory. A first static storage allocation in the RAM memory is associated with the virtual machine and a second static storage allocation in the RAM memory is associated with the class module. During startup, the virtual machine searches for a module of a given name. If the module is found, a given function is called in the class module so that the address of static storage associated with the class module can be saved in the static storage associated with the virtual machine. The address is used later when another function is called. The static storage associated with the class module has a table of pointers to external functions. There is one pointer for every external function. If an address of an external function is not known, the address of the external function is looked up by name, and the resulting pointer is saved in the table of pointers, so that the address of the external function does not have to be looked up again. The table of pointer…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.