Setting up SNA networking with Hercules using DLSw

I finally broke down and made a quick video on setting up the DLSw ‘lab’ that I had uploaded on Internet Archive.

See it works!

Although I should have gone more in depth with the cisco part.

Namely showing how to check the interfaces, the ethernet l2 traffic, how the DLSw peers, and then the establishment of the circuit once the session is established.

But I wanted to be quick. I don’t think I can edit a video that is up so I’ll probably follow it up with another quick video.

simple network diagram

Trying to put it into words, the Windows 3.1 VM hosts Extra! 4.2 talking SNA to the Loop_SNA virtual Ethernet interface, which then is connected to the virtual cisco router, which also has a TCP/IP enabled interface, Loop_TCPIP, which the host Windows 10 machine can talk to, allowing it to communicate with the Hercules VM which I had compiled to run as a native Win64 EXE for Windows.

Basically, at it’s heart, this is the important part of the cisco config:

source-bridge ring-group 1
dlsw local-peer peer-id
dlsw remote-peer 0 tcp
dlsw mac-addr 4000.1020.0100 remote-peer ip-address
dlsw udp-disable
dlsw transparent switch-support

interface FastEthernet0/0
 ip address
 no shut

interface Ethernet1/0
 dlsw transparent redundancy-enable 5555.5555.5000
 dlsw transparent map local-mac 4000.1020.0100  remote-mac 4000.0999.0100
 no shut

I used a ‘clean’ VMware virtual machine to host this test, just to show how to do the setup from scratch, taking nothing for granted.

Hopefully this explains it a bit better for those who wanted to know, along with the video to show the high level of it working. Not sure anyone would want to watch me stumble through setting up MVS, along with going into more detail on the cisco config & workstation config.

As always, thanks to 9track for providing the patches, and showing that this whole setup was possible!

BSD on Windows: Things I wish I knew existed

Yahoo Auctions Japan

It’s 1995 and I’ve been nearly two years in the professional workspace. OS/2 is the dominant workstation product, Netware servers rule the world, and the year of the Linux desktop is going to happen any moment now. If you weren’t running OS/2, you were probably running Windows 3.1, only very few people were using that Linux thing. What would have been the prefect OS at the time would have been NT with a competent POSIX subsystem, but since we were denied that, enter Hiroshi Oota with BSD on Windows.

It was a late night browsing yahoo auctions Japan as one does, laughing at the absurd Famicom/Super Famicom games, and I went ahead and looked for BSD CD-ROMS, where I first came across BSD on Windows. And then I’d forgotten about it and went to work on some Darwin projects.

Fast forward 3 weeks, and vic485 had bought it, had it shipped, and uploaded on So a big super thanks to vic485 for making this all possible!

So what is it? It’s not quite BSD, its a bunch of 16bit DLL’s that broke the kernel down into subsystems, that each rely on winmem32.dll to give access to flat/32bit address space. BSD on Windows (BOW) being a hybrid 16/32bit app is originally for Windows 3.1, with the later 1.5 update for Windows 95, which includes support for long filenames. I’m not sure if it’ll run on Windows NT or OS/2, as I don’t think

So what do you get?

The key media contents are the install floppy and the CD-ROM. Yes the setup program IS only on the floppy. Hope you get that disk image. I’m unsure what the manual is like, other than of course it is in Japanese.


It’s very much a single user mode BSD like environment complete with vi/gcc/csh/perl just to name a few. I’ve been able to test job control, and building some simple programs like Hack 1.03. I found a few issues however.

I haven’t tested enough with FreeBSD 1/2 but I can verify that from my ‘Ancient Linux on Windows‘ packages, the object format is the same, which is that early era when everything was a.out, although all different the reliance on GNU GAS & LD did make the object format the same. And it was nice to compile a hello world from my Linux cross compiler, link it on BOW, and get a running executable.

The memory is weird, in that you can add hundreds of megabytes to Windows and BOW will always run exhausted. In the bow.ini file you can set the heap for each program, and I found out from some silly trial and error that the maximum heap you can effectively give is 13 megabytes. It seems that winmem32 has a single chunk of memory where all processes run out of, hence the sub 16mb ram zone. Maybe there is a way to allocate it, but I’m unsure, maybe it’s in the book. CC1 was frequently having issues, so setting it’s heap to 13M sure helped, the linker ‘ld’ of course was running out of memory as well so setting it to 8M got me linking.

Filenames, especially on Windows 3.1 are a huge problem. All the LFN TSR’s I tried to load just resulted in a full crash. I had to point the linker to the CD-ROM live filesystem, which maybe would be tedious on a real machine, but under emulation it’s fine.

BOW does NOT like Qemu. At all. It won’t under otvdm either. I suspect NT is a no go but I haven’t tried. Oddly enough it’s not a timing issue, as it does run under VMware. There is an advantage to running it under Windows 95, is that it supports long filenames. 86Box works as well, I even was using the Pentium II Xeon at 400Mhz and that ran fine.

Probably the most annoying and silly thing is that the GCC C compiler doesn’t have C++ style comments turned on. Not being able to use ‘//’ is quite annoying.

Hack 1.03 running on my PS/2 model 80

Hack ran fine on my 386, which was a pleasant surprise!. It was really cool to have Word+Excel and Hack running at the same time.

Had I known about this, it would have been an incredible bridge product. Not to mention cross compiling to even Win32, or Linux. Not to mention at the time being able to run BSD with no real pain, just install and go

simple IRC test

There is generic TCP/IP Winsock support in BOW 1.5 as it simply calls winsock. This also includes the ability to run daemons, however limitations in BOW are quickly exposed, such as missing setuid/setgid sno there is no ability to impersonate lower privileged users. MMAP stuff also doesn’t seem to work, although I was able to build a super simple port of Apache 1.3.1 to BSD on Windows (BOW). 

While BOW may appear to be very BSD like, there is a lack of a the mmap Apache needs, along with user mapping & impersonation.  I ended up using the EMX – OS/2 system code, since it’s very POSIX like without relying on the Unix like OS actually working.

I’ve been able to serve pages to myself, however BOW crashing out many emulators and hypervisors kind of stops me from putting it on the internet. BOW enthusiasts can download it from

Today, there is really no point to BOW, it’s an interesting oddity, but back in the day, for a jr network administrator being able to run the Unix version of the snmp tools, even if it’s only client side would have been great. If tftpd could be built to run this would have been beyond amazing, as you not only get BSD, but full Windows apps at the same time, much like MachTen.

It’s a shame I never knew this was a thing, I certainly would have been evangelizing BOW! Who knows what other treasures are in the parallel societies of Japan/Asia/Europe?


Ive been able to cross compile from Windows to BOW using an old 386BSD 0.1 cross tool chain. You can read about it here: Cross compiling to BSD on Windows (BOW) from Win32

As reported a few days ago the Windows patches for FreeDOS were committed!..

a couple of weeks ago.

This will be the perfect follow up to the aptly named previous post FreeDOS running Windows 3.1.

I’ve haven’t built the FreeDOS kernel in a while and I have to say it’s pretty easy. I’m taking the easy way out here, so I’m using OpenWatcom v2, because I figured the tools should be both at least Win32/Win64 and halfway up to date. Don’t get me wrong, MS-DOS Player is a fantastic app but I don’t want to lean on it for 100% of the build.

I configured it for something in my mind generic with the following flags:

build fat16 wc 86 win

Naturally it had issues with 3 executables, two of which are generated as the project builds, and I just did some silliness to have MS-DOS player make ‘native’ versions: patchobj.c
        $(CLT) $(CFLAGS) patchobj.c
        msdos -cobj.exe
        -rm -f
        -ren obj.exe patchobj.exe

exeflat.exe: exeflat.c ../hdr/exe.h
        $(CLC) $(CFLAGS) exeflat.c
        msdos -cxeflat.exe exeflat.exe
        -rm -f exeflat.exe
        -ren xeflat.exe exeflat.exe

The same went for sys\bin2c.exe but it’s not rebuilt every time so it doesn’t matter.

And with that in hand it boots. YAY

And now for some absolutely unfair testing. Before anyone complains, yes this is absolutely unfair I mean hell if you bought Windows 3.1 in 2021, I guess get OS/2 or just keep digging at the yard sale and get MS-DOS. Anyways here we go:


Turning off InDOSPolling gives this lovely crash. Naturally then it’s still required.

My go-to test, Running Infocom/FASA BattleTech Crescent Hawk’s Inception in CGA mode in a Window hard locks the VM before anything is drawn to screen. Bummer. And that is pretty much the story of FreeDOS under Windows on this build. Again it’s 2021 who even needs Microsoft VDMs?

That said there must be some weird hook in MS-DOS that Win32s relies on. Just like before Win32s fails to run.

The holy trinity of ‘bad’ Windows 3.0 games, Sim City, Sim Earth and Sim Life work just as they did in the prior version, with Sim Earth instantly quitting. Not sure what is going on there. It does launch with virtual memory enabled, but then proceeds to corrupt all the file handles and Program Manager loses it’s mind. In the productivity front Excel v3, and Microsoft Word v2 run fine. Yay!

Windows 3.1 is serious business!

So in conclusion doing Win16 things in Windows 3.1 is seemingly fine.

FreeDOS running Windows 3.1

Yes, really it’s FreeDOS running Windows 386 Enhanced mode. For real.

perditionc posted this over on the freedos list:

Hello everyone,

So it took me a bit longer than I planned, but below is the
information needed to reproduce and links to sources.  (Be kind, I
know that the code needs more work.)

To see it in action, from installing FreeDOS & Windows to running I
posted an updated the video (about 4 minutes, sped up some stuff and
cut some scenes down but its originally a single recording from first
boot until the end)
download boot disk -
kernel *** requires patches, see below for source (FreeCOM)

have available Windows 3.1 install media (*** not provided ***)

create a virtual machine (or have a compatible real computer)
example has a 200MB hard drive with 32MB of memory and otherwise
virtual box's Win 3.1 default settings.

boot FreeDOS floppy
create a primary partition, don't use FAT32, use all available
space, ensure active
reboot so kernel see new partition
format the C: drive and set label as desired
fdisk /MBR
install master boot record so hard drive is bootable
sys C:
install system boot record and files to C: partition
copies kernel.sys and to C:
copy c:
copy EDIT.* C:
so have available after install Windows
Optional: take out (disconnect virtual) floppy from drive and reboot,
ensure hard drive boots
Optional: create a CONFIG.SYS and AUTOEXEC.BAT so not prompted with
date and time
Install Windows
put in first Windows floppy and run SETUP
follow prompts until complete, allow it to modify CONFIG.SYS and
Optional: edit AUTOEXEC.BAT to load SHARE.COM
(if you do not do this step, you must remember to do so before
starting Windows)
Edit C:\WINDOWS\SYSTEM.INI (adjust based on actual installation and
editor of choice)
find [386Enh] section, at bottom add line:
save file
start Windows, will be in Enhanced mode if supported
Kernel patches -
rest of sources (kernel, FreeCOM, format, fdisk, sys, share, edit) -

Bart, Tom, and others who have improved the FreeDOS kernel to where it is today
All the other FreeDOS developers, especially for FreeCOM, FDISK,
And Eric who's original research helped with the initial
implementation of the necessary patches a decade ago

I will be working on improving the code, specifically the critical
section handling and hopefully remove the need for the InDOSPolling
flag being set as well.


And sure enough I was able to reproduce Windows 3.1 from the binary. I haven’t looked at patching/building yet.

Turning off virtual memory let’s FreeDos run in a Window!

Even more amazing to me BattleTech 3025 can run CGA mode in a Window too!

I should add that VMWare player didn’t work, nor did later versions of Qemu either. I had much better luck with my mutated Qemu 0.90 fork thing. ISA Cirrus card for sure!

Being able to run Windows 3.1 in 386 Enhanced mode has been one of those holy grails of compatibility. It’s great to see this in action!

I should add that Windows/386 and Windows 3.0 don’t work. 386 needs some versioning set, and 3.0 is convinced that the memory is too fragmented or that C: is really A:. Also Win32s doesn’t work either, but still Sim City, Excel and Word run fine!

As a follow up, 3.11 for workgroups or not doesn’t work either.

Fun with Caldera WABI

(This is a guest post by Antoni Sawicki / Tenox)

In the previous post about SCO Merge I briefly mentioned WABI, which is a Windows ABI emulator for Unix. Initially released by Sun Microsystems, it’s believed that it came with acquisition of Interactive Systems Corp (ISC) and Interactive UNIX. It was available for SPARC, x86 and PowerPC Solaris as well as IBM AIX. Around 1997 it was released for x86 Linux by Caldera. This article will focus on Caldera’s version specifically.

Although entirely possible to install WABI on another RPM based distribution such as Red Hat, I’m a purist and wanted to try it on Caldera Open Linux. The install is pretty straightforward you mount the iso file and run install script. In a next step you need to install an update to version 2.2D. This is done by replacing /opt/wabi/bin/wabiprog with extracted version of this file. Thanks to readers of this blog post for sharing these.

When launched for the first time, you will be prompted to provide copy of Windows 3.1. This the main difference with WINE which specifically does not require copy of windows to run apps. I have noticed that WABI is rather picky about lower vs uppercase when installing software. There is an utility called wabimakelower to help there. You can also add an icon to one of Caldera Linux / Looking Glass program groups.

Once you run it, it’s Windows 3.1 as usual:

WABI was designed for running productivity apps such as Office:

You can even run Visual Studio:

Curiously WABI is not a MS-DOS emulator. In order to run DOS apps you need to install such and configure it in WABI Control Panel:

For the lazy, a readily preinstalled version is available as OVA and 86box. Root password is “caldera”.

There also is a User Guide in PDF.

Have Fun with Virtualization!

Adding DOSBox’s MPU401 to Qemu 0.90

I thought this may be something cool, if not kind of pointless. Anyways the MPU401 UART can be run like a traditional serial port with an IRQ, in intelligent mode, or just as a ‘dumb’ device you can just bit bang to talk to MIDI devices. So while playing with DOSBox I thought it’d be fun to take it’s emulation and plug it into Qemu.

And this is the end result.

It’s far from perfect, when it works it does tend to work well, although it fails to work with things like Return to Zork, but it does work with DMX’s sound code in DooM and the MPU401 driver for Windows 3.1

While doing this I was originally struggling with mapping the IO ports. Qemu has some functions to map in the memory model to assign a function that will trap read/write space. In this case base is 0x330 the base of the MPU401 device.

register_ioport_write(base, 8, 1, mpu401_ioport_write, s); register_ioport_read(base, 8, 1, mpu401_ioport_read, s);

I was thinking that the port 0x331 needed to be mapped in the same way, but it turns out after looking through more of the source, it’s actually a word aligned access. So in that case you can use a switch to see which port is actually being accessed.

static uint32_t mpu401_ioport_read(void *opaque, uint32_t addr) { switch(addr&0xf) { case 0: return(MPU401_ReadData(addr,0)); break; case 1: return(MPU401_ReadStatus(addr,0)); break; default: return(0xff); break; } return(0xff); }

Pretty simple, right?

And from there it’s a matter of mapping the DOSBox MPU code, along with the Windows interface code. Since I’m not using intelligent or IRQ mode, I just amputated the code where applicable.

If anyone wants to look at what I did to merge into anything else (and probably do a better job!) it’s on sourceforge as mpu401.c.

Otherwise the binary is available on sourceforge:

Download Qemu090b

MSDN from October 1994

I picked this 20 disc set recently and ugh the cringe is just… insane.  And yes, that is Bill Nye


STUDS from Microsoft .
(Video in MPEG-1/Audio MPEG-2 care of JSMpeg).

I had this ages ago, although I couldn't remember if the NT 3.5 SDK/DDK had shown up at this point, but it's only the Japanese version in this set.  Since I'm having such a PITA in tracking down a 3.5 set, and I'm not sitting on this, I may as well archive it.

Yes, I had to rip 20 of these!

So you too can find the early Video for Windows, and all kinds of other things from the mid '90's on

Or Wallpapers like this 'puppy' from the Japanese version of Windows 3.1

WineVDM is improving at a dramatic rate

It’s incredible how much it’s improved since I last touched on WineVDM, the port of Wine to run on Windows using the MS-DOS Player (and Mame 80386 emulation) at it’s heart.

The latest source build WineVDM_2018_07_30b.7z is now capable of loading and running Sim City for Windows 1.0.

I found it best to install Windows 3.0 into DOSBox, and then your application.  After the install I copy the application so the physical drive of the hosts matches where it was installed, and then unpack the 7z build archive into that directory.  There is a ‘WINDOWS’ directory and I xcopy the installed Windows directory into there so it has all the INI files, fonts and all that jazz.  To make sure it doesn’t conflict I delete the following from Windows 3.0:

del windows\system\*.drv
del windows\system\*.exe
del windows\system\*.mod
del windows\system\WIN87EM.DLL

Since these files are most certainly going to be emulated by WineVDM.  After that it’s time to run stuff!

130 KLOC!

I should also add that I’ve been able to use QuickC for Windows, and build a ‘non trivial’ program, the Fortran f2c compiler weighing in at 104,245 lines , and use that to compile 16,182 lines of Fortran 77 into C, and then compile the resulting C + the Fortran runtime library a staggering 130,405 lines of code, and the resulting binary works, just like it did on Windows 3.0!

I’ve also been able to print a text file using Microsoft Word 2.0 much to my amazement, although anything involving fonts just locks or crashes.  I can’t say I’m all that surprised.

And yes, it does in fact run SkiFree 1.0

SkiFree on WineVDM

So no need to wait for Win3mu, there is WineVDM which is being developed RIGHT NOW, and the source is already available.  You can see my notes on building it here.

UX lessons from the Magic Screensaver aka After Dark

I found this kind of interesting, a breakdown from the original guy behind the once popular After Dark screen saver.

As it started as an experiment on Windows 2, it became a product on it’s own, and launched an entire industry, along with being copied by every major OS vendor.  In the 90’s having a screen saver was key, just as having simple games like solitaire, especially a broken shuffle one where the user wins most of the time led to Windows being heavily favored in the work space.

Magic Screen Saver for Windows 2

So for the heck of it, I figured I’d check it out, and as always thanks to Jason Scott, there is a copy of 1.02 on And as reported it’s basically the ‘mystify your mind’ screen saver.

Magic in action

The runaway hit Magic Screensaver became After Dark, which then had several licensed addons like the Simpsons, Star Wars etc.  Back then themes for Windows were popular along with sound effects.  A lot of the functionality is still in Windows, although most people prefer that their machines are silent, only making audible alerts if there really is something wrong.  But back in the day a ‘multimedia desktop’ was a $5,000 noise maker, and not many offices were impressed.  Which of course gave rise to the ‘office sound card’

All Business and no fun!

Naturally under Windows there were virtual device drivers to emulate a sound blaster, as people still wanted to game with this cheaper ‘business audio’ card, although with the rise of Windows 95/Direct X gaming under Windows finally became a thing making Sound Blaster compatibility a thing of the past.

But going back to After Dark, they made a fatal error of teaming up with Berkeley Systems, who eventually started to make their own releases pushing the original team out of their own product.

After Dark 1.0 and the infamous flying toasters.

The toasters became focal in a few lawsuits, namely the Jefferson Airplane album, although it was dismissed as the artwork for the album had not been trademarked!  And they were able to force the Opus ‘n Bill screen saver where Opus shoots the toasters.  Late they changed the toasters to have propellers to avoid being too similar.

Opus shooting a flying toaster

Oddly stuff like screen savers too have largely fallen out of fashion with the rise of power saving monitors that just turn themselves off either from a lack of new images, or a signal from the OS.

One of those weird legacy things that in today’s world really doesn’t have that much meaning, but a scant 20 years ago was a major industry.

WinDooM on SoftPC, on SheepShaver

So I was hammering out something with SheepShaver (more on that later!) and I thought a quick test of just how fast SheepShaver is vs a real PowerMAC would be interesting.  So I was playing with my old copy of SoftPC, which is 68000 based, but There were PowerPC versions, years ago when I bought a G4 to run OS X to only find out that it wasn’t supported (the dark days of OS X Server 1.0, before the 10.0 public beta) I used to run Windows NT 4.0 on SoftPC on MacOS 8.6.  Ugh, dark times indeed!

So with some luck, I got SoftPC 3.0 up and running on MacOS 7.5.3 using SheepShaver for Windows. Then I noticed that unlike SoftPC for the 68000, SoftPC for the PowerPC emulates a 486!  So how does DooM run?  A little slow, it’s kind of dream like.

But since there is Windows and a 32bit processor, I thought this would be a great time to load up Win32s, Video for Windows, WinG, and WinDooM!

WinDoom on SoftPC

WinDoom on SoftPC

And much to my amazement it runs!  And I was further impressed that there is a shim sound driver, and it works!

So I made a quick video to compare DooM for Windows vs DooM for MS-DOS on this setup.

Yes it’s pointless, but I kinda think it’s really cool.

As a bonus, here is E1M1 under MacOS 8.0.  The MIDI support in 8.0 is MUCH more stronger than 7.5.3!  And I should add, it actually feels faster on 8.0 than 7.5.3