2009 Mac Pro 2 x quadcore CPUs Yosemite 10.10.5 This machine has loads of unused capacity. My wife’s G4 is stuck at Leopard. We share an office and are within arms length of each other. I have 2 PCI video cards, two monitors and a spare keyboard and mouse. Rather than buy a replacement computer for her why not timeshare my capacity? Why not map one HW set (monitor, KB,Mouse) to my account? And the other to my wife’s account (on the Mac Pro.) That way we can concurrently use the system. IOW recover the inherent timesharing capability of Unix. (I come from a timesharing background many years ago,) My questions are: 1. Is it feasible to implement/recover the timesharing capability? For example by allocating specific HW to a specific user? If not why not? Is the dispatcher (GCD?) capable? 2. I see that with two users logged on there are 2 window manager instances, one per account. With Fast User Switching the devices remain the same but with different window managers. 3. Where would I look in the Apple Darwin Open Source to investigate what happens in Fast User Switching? The Mac OS X Internals book only has 1 paragraph on page 119 that is merely descriptive not technical. I've worked on mainframe timesharing OS' so am not afraid. Perhaps it can be done with a kext? Or else build my version of xnu? TIA for you advice which is hereby solicited. respect Peter _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app... This email sent to site_archiver@lists.apple.com