Re:How Quake.exe got its TCP/IP stack
by toast0 on Tuesday November 18, 2025 @11:02AM
(#45968032)
So... Win32 runs in virtual mode. In 2025, we don't think of that as a Virtual Machine, but it totally is. Hardware access is trapped by the CPU and processed by the OS/DPMI server.
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Re:How Quake.exe got its TCP/IP stack
by fredoralive on Tuesday November 18, 2025 @02:22PM
(#45970745)
No, in 386 mode 3.x and 9x the System VM and other DPMI clients runs in protected mode.
Virtual 8086 mode, as its name somewhat suggests, only runs real mode code.
Re:How Quake.exe got its TCP/IP stack
by trollbridge on Thursday November 20, 2025 @01:46PM
(#45996139)
It's not a virtual machine. There is no hardware machine that presents itself to function like a protected-mode ring 3 task on an 80286 or an 80386 functions. And the 286 and 386 both lacked a "virtual 286" and "virtual 386" mode (although it would have been almost-trivial for them to support it; Intel just decided not to, probably figuring it wasn't important).
Virtual 8086 mode, on the other hand, does behave exactly like a real 8086, which otherwise would have been very slow to implement on a real 386, and was either very slow on a 286 or impossible due to the 286 having some errata that prevented normal virtualisation techniques (the 286 had some non-restartable exceptions).