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Windows 3.x ran 16-bit processes in unprivileged sandboxes. If a process tried to directly use system-level features like segment descriptors and page tables, it would crash. It could ask the actual kernel to perform similar operations on its behalf using DPMI, but it was the process's responsibility to know to do that. The heroic measures that VMware had to ...


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In addition to the answers already given, the term virtual machine can also refer to a process virtual machine, i.e. a runtime environment executing platform independent bytecode[1]. The best known example today is probably the Java Virtual Machine (a version of which existed for Windows 3), but process virtual machines go back much further. Prominent ...


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"Virtual machine" has a long and varied history, not always meaning exactly what it means today. Early designers of timesharing systems viewed what they were providing to their users was a virtual machine. In the terminology of the time, the user could act like he had a computer all to himself. This computer wasn't identical to the hardware; it may ...


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I would think the articles you've read were most likely about the Virtual 8086 Mode introduced with the 386. Here a host OS (running at privilege 0) would create a standard protected process, but mark it as VM86 when starting. In turn the process will be restricted to real mode addressing (16 bit segment and offset) and a 1 MiB address space. Despite the ...


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