The thing is that the WINE project currently does and will continue to provide the userspace logic to allow this. ReactOS is a heavy user of WINE, and differentiates itself in that they are recreating the most basic components of Windows, including the kernel in hopes of getting a binary-compatible driver layer.

Long-term compatibility will be provided by the WINE project. ReactOS is only necessary if you need to run Windows-specific drivers, and I don't see that being useful in 10, 15, or 20 years. We have other systems that can provide kernels, driver, and other low-level interfaces (like a basic shell) and depend on WINE in userspace to preserve compatibility.

I believe that ReactOS relies on large portions of WINE for support, and simply provide the base platform and windows desktop bits.

I believe that code (and ideas) flow both ways between the WINE project and ReactOS

If you'll need XP-era software in the future, you'll just run it inside a Win XP VM. Same for DOS software. Same for any software who will outlive its initial host (open-source or not) and will not be very simple to tweak and recompile (even if you could tweak and recompile it, you might choose to just run a damn VM anyway out of pure laziness or for cost/time savings...)

I think a Win XP VM could solve most people's needs, but personally I think it's fantastic that we will have several different solutions such as ReactOS, Wine, and VMs. Eventually you will run into something that won't work on your preferred solution.

It's also nice that they work on different levels. Wine let you run an legacy app on your regular OS, while a VM would give you the entire operating system to fiddle with.

Most people won't be able to legally run XP VMs once the XP activation servers go down.

That's where something like ReactOS fits in. Right now you can legally use a DOS VM running, say, FreeDOS (or an emulator, like DOSBox). There's no freely-available Windows XP equivalent. Sure, sure-- you can run Windows XP illegally w/ a volume license product key (to skirt product activation w/o modifying the product) but that's not a solution that "works" in many cases. It's technically very easy to run a Windows XP VM-- it's very challenging, legally.

If you are running Windows 7, you can run XP legally for free: http://support.microsoft.com/kb/958559

I could see a huge market for Amazon or Google to step in and provide cloud based Legacy systems for large corporate clients. ReactOS could provide a nice foundation for that.

It wouldn't be as efficient, but wouldn't virtualization solve this problem in a cleaner and more maintainable way ?

No. It allows you to run Windows-in-Linux, but you're still relying on non-Free software.

Isn't virtualbox GPL ? For the non Free part of running windows, if your goal is to run windows only legacy software, chances are it's not Free as well.

Good point - but seems better to me to run a single specific, non-free app (which may or may not depend on the manufacturer's servers to function), than to add another non-free dependency to it (i.e. XP), which definitely _does_ require manufacturer's permission (i.e. activation servers) to function normally.

Yes, but you'd have to install Windows onto that, and it's not.

Why is that a good thing for the world? Serious question. Why should we enable businesses that don't want to develop modern software? Doesn't this hold back the world in terms of productivity and software quality?

as an example: scientific instrumentation manufacturers are rather bad about keeping their software up to date, and some of them are good about making instruments that will run for decades.

it is hardly anything-friendly to toss a working, expensive instrument because you can't buy a computer that will run ancient-OS-whatever anymore, or they EOL'd the OS and you can't get patches, etc.

there isn't enough diversity/competition/whatever in the market to shop for instruments on the basis of software quality. sadly.

Yes

This is a huge pet peeve of mine. Most equipment is "Windows based" today

It is "ok" if it's fully built-in, still vulnerable to network/USB exploits, though.

The main issue is when it's a USB/PCI device, and then you have to provide the computer to run it, and of course, there's probably not going to be support for the next versions.

This is usually equipment costing 5 to 6 digits

The side of the coin: Why are we wasting time re-writing software that is already done? How is that progress?

Because the already-done software (e.g. XP) has serious issues; namely, even if you have obtained it legally, you can't legally install and run it without the manufacturer's explicit consent (activation servers will go down some time after EOL - after that, you can either go illegal and crack your copy, or you can't use it at all). In other words, it's timebombed. (Note that I'm not passing judgement on this - just stating the existence of such condition.)

For a home user, this is a non-issue (as "meh, just get a new OS" is also an option, due to commodity hardware); for an organization, this is big trouble (as neither "so we'll use the OS illegally, whatever" or "so we'll throw away the equipment we now can't use" is an option).

Or Microsoft could issue a hotfix to remove the license check. Adobe has such unlocked version of CS2.

Which is something which might happen, or perhaps not, and is entirely under MS's control and discretion.

IMNSHO, this is a very unlikely scenario - the (misguided) reaction of the general public would be something like "oh look, XP had its antipiracy protection disabled by MS, which means it's now free to use; who needs Win8 anyway?" I can't imagine MS essentially undermining one of its core cash cows (Windows) anytime in the near future, especially as the "meh, just get a new computer with new Windows" line has proven effective in most cases. Also, as I have yet to see this to happen to any deprecated and truly obsolete MS product (Altair BASIC? MS-DOS? Windows 3.11?), I don't see that happening to a product which is anything but disused.

It is easy for me to imagine them doing it, if they wait enough time, that most new hardware has no XP drivers anymore, and most programs/games depend on higher versions of windows APIs, the general public will not care about the then obsolete XP, just like they do not care about DOS, or Windows 3.11 and so on.

I agree that this is an act of kindness, that can not be depended on and it is entirely under MS control when/if it will happen.

Haven't we learned a fair amount since the days of XP-specific software? I've never seen an enterprise XP application that was "done." Only shipped. Don't we have better platforms now that make it easier to write responsive and stable software?

Why waste time rewriting Unix...

It's just as likely a can't rather than want. I can see some value allowing old software to continue to be useful, even for just data export purposes.

There's little other creative or "intellectual property" that becomes non-functional after only ten years. Compared to, say, movies or photography.

just for gaming history it's worth it. Freedos allow me to play some of my old games. And there was a lot of good games on windows xp, so i hope that people could still play them.