DMB@PSUVMA.BITNET (10/14/86)
OK Guru's let's have it! What is envolved with a multitasking O/S for the Mac? No snide remarks to the effect that it can't be done, let's assume it can but will be slow. ------------------------------------------------ Process Swapping - What needs to be saved All registers. General Purpose/Status/etc.. Code Segments - either in memory or on disk Protection registers for each segment Priorities, other status information Segment map table,other location tables ......... ......... Screen management -> Many Solutions, one may be Menu Bar is for the system only (task info,system services,launches,etc) Processes run within subscreens (we know them as windows) Each process has it's own "system window" including menubar Current Process window is NOT updated on task switch Screen Dynamics are handled by user commands (mouse clicks, etc.) Other Considerations All I/O should be Asynchronous - increase device demand by putting processes to sleep if waiting for I/O Is there memory protection in the hardware for segmented addressing? ............. What else/ what problems/solutions,etc. dave