Linked by Thom Holwerda on Mon 5th Feb 2018 23:08 UTC
Windows

In November last year I wrote about the forgotten and obscure feature of early Windows 95 builds that lets you run Windows 3.1 in a window on Windows 95. Since then I was wondering if this would still work on the final build (950) of Windows 95, considering so much has changed since build 58s.

I won't spoil it.

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Reminds me of OS/2 2.0
by malxau on Mon 5th Feb 2018 23:47 UTC
malxau
Member since:
2005-12-04

OS/2 2.0 (1992) had a full screen Windows 3.0 environment, which also had a minimized icon that would switch back to OS/2 when clicked. In order to make this work, Windows needed to defer memory management to OS/2 via DPMI. It also had a "seamless" mode which used video driver trickery to display Windows on the same desktop (and overlapping with) OS/2 applications, and of course that needed the dual mouse drivers etc.

Seeing this makes me wonder how much code, or at least inspiration, was shared between the two.

Reply Score: 6

RE: Reminds me of OS/2 2.0
by galvanash on Tue 6th Feb 2018 03:47 in reply to "Reminds me of OS/2 2.0"
galvanash Member since:
2006-01-25

Once you have MSDOS virtualized there is very little left to do to be honest... Windows 3.1 was basically a DOS application. The only obstacles are presenting it with compatible virtualized hardware (video card, sound card, etc.) with working windows drivers for them.

You can still do this on Windows 10 if you like btw, just use dosbox:

https://www.howtogeek.com/230359/how-to-install-windows-3.1-in-dosbo...

Or if your nostalgic and want to do it the old school way (and can get your hands on the version of WINOS that OS/2 used with DPMI support) you can use dosemu on Linux to do it (this has worked for like 20 years)

http://www.dosemu.org/docs/README/1.2/windows.html

Of course nowadays there is little point as dosbox exists on Linux now...

Reply Parent Score: 2

RE[2]: Reminds me of OS/2 2.0
by Darkmage on Tue 6th Feb 2018 08:20 in reply to "RE: Reminds me of OS/2 2.0"
Darkmage Member since:
2006-10-20

Except Dosbox still fails to emulate a lot of timings correctly and runs slowly in a lot of cases. It's a brilliant piece of code/emulation, but still flawed. This isn't written in anger. The Dosbox developers are some of the loveliest people on the internet. I suspect there are limits to what a PC can actually do to emulate PC architecture and it wouldn't surprise me if Dosbox is hitting those limits hard.

Reply Parent Score: 5

RE[2]: Reminds me of OS/2 2.0
by Z_God on Tue 6th Feb 2018 19:00 in reply to "RE: Reminds me of OS/2 2.0"
Z_God Member since:
2006-06-11

Note that you can run the regular Windows 3.1 on DOSEMU for many years already.

Reply Parent Score: 1

RE[2]: Reminds me of OS/2 2.0
by Drumhellar on Tue 6th Feb 2018 21:28 in reply to "RE: Reminds me of OS/2 2.0"
Drumhellar Member since:
2005-07-12

Windows 3.1 was basically a DOS application.


No, it wasn't. It was an actual operating system, really, by any reasonable definition of the word. Basically, everything that an operating system does, Windows 3.1 without using DOS, and handled many things that DOS couldn't.

Sure, it started from DOS, but when you launched Windows, it would replace DOS with a 32-bit hypervisor that would run a virtual machine with a single instance of Windows 3.1, as well as DOS virtual machines for running DOS apps. The Windows 3.1 instance and the DOS virtual machines were pre-emptively multitasked.

As for the Windows 3.1 machine, it provided virtual memory (including paging to disk), its own interrupt handler (and didn't use DOS's), it used its own drivers for disks, mouse, audio, printing, and networking (When available - it could also use DOS drivers if Windows drivers weren't available). The disk driver is especially significant, as it as a 32-bit protected mode driver that completely by passed DOS and BIOS function calls.

Sure, it was closely tied to DOS, but it was definitely an operating system in its own right, and certainly not just "basically a DOS application."

It's really more like... an operating system that runs next to DOS, and sometimes asks DOS for a cup of sugar or whatever.

Reply Parent Score: 7