Hi! > At the moment I know next to nothing about that "virtual x86 mode" - and > I was hoping that CPU can be made to switch to that mode and then to boot > even different OS into each "instance"
That is exactly what Windows does, but the instances are called tasks. Because DOS is not task-aware, Windows has to catch everything which DOS believes to be single-user and redirect it into multi-user :-) You can run dosbox as a DOS app with HX RT, but just one instance. The trick with virtual x86 mode is that it hides the protected mode and task details from the "instance", so creating vm86 tasks means extra work for the creator. For example emm386 puts itself into protected mode and transplants DOS into a vm86 task, but makes use of the fact that only a single instance of DOS exists. The emm386 of DR-DOS already contains some preparations for swapping tasks, which makes it more complicated. Tools like desqview also use protected mode and vm86 tasks to keep track of user interaction attempts of DOS and let you swap between several DOS apps, which must all run in full screen mode. They are more powerful than MS DOSSHELL which I believe to use no protected mode: It probably only intercepts BIOS calls to keep track of the hardware state expected by each app when you swap between them. By the way, DOSEMU2 is aiming to also work on Windows, not just on Linux. It has a built-in CPU emulation for situations where no vm86 tasks can be acquired. Seems common in our 64-bit age. Cheers, Eric _______________________________________________ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
