PPT Slide
- The SOS C++ code for the System Call Interrupt Handler is fairly identical to the JavaSOS version - a giant switch statement with cases for each system call.
Copying Messages between Address Spaces
- The SOS version has two simple routines that do memory copies using the particular process’ base address.
- JavaSOS accomplishes this with the separate memory routines found in HWSimulation.java:
- GetCell() / SetCell() - Read relative to base+bounds
- GetCellUnmapped / SetCellUnmapped()- Absolute read
- GetCellUnmappedAsInt() - Absolute read of an Integer