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Comment by littlestymaar | Hacker News Reader

> is their narrow criteria for "emulator" that nobody else seems to use.

Except the people actually writing or talking about real “emulators”. You know, for things like NES or Gameboy on x86, x86 on WASM, etc.

Sure, you can argue that VMs or Wine are emulators in the broadest sense, but then I could argue that your CPU is an emulator too since it doesn't really runs ASM, and with that very loose meaning almost anything computers related is an emulator. And in practice that's never what people mean when we're talking about an emulator. (Even this thread started with the wrong postulate that WINE must have incurred a performance penalty because the commented believed it was an emulator).

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Wine-like things have long been called emulators.

When I was at Interactive Systems Corporation in the mid to late'80s and we were porting System V Release 3 to the 386 for AT&T, we wrote a Wine-like program called i286emul to run 286 System V Release 2 binaries. We and AT&T called it an emulator [1].

Later AT&T and Microsoft and Sun were involved in various projects to merge features from System V R3, BSD, SunOS, and XENIX into System V R4. As part of that they wanted a way to run 286 XENIX binaries, and Microsoft contracted with Interactive for that. We wrote another Wine-like program for that called x286emul. We and Microsoft called it an emulator too [2]

The XENIX emulator led to the stupidest meeting I have ever had to attend. Microsoft said there was an issue with the kernel that could not be resolved over the phone or email. So me and the other guy working on x286emul had to go to Microsoft for a meeting.

A flag needed to be added to the process data structure that would tell the kernel to make some slight changes to a system call or two, due to some differences between System V and XENIX. It was something like XENIX having separate error codes for some things System V rolled into one, or something like that.

The meeting was about how to set/clear that flag. Microsoft wanted to know if we preferred that it be done as a new flag to an existing system call or if a new system call should be added. I looked at the other guy from Interactive and said something like "A flag's fine for me", he said he agreed. We said "flag" to Microsoft, and the meeting ended.

That couldn't have been handled by phone or email?

[1] http://osr507doc.xinuos.com/man/html.C/i286emul.C.html

[2] http://osr507doc.xinuos.com/man/html.C/x286emul.C.html

Things like Wine used to be called emulator, but this usage fell out of fashion a while ago. Now the word “emulator” has been generally refined to mean a (inherently slow) hardware emulator, and most of the compatibility layers explicitly market themselves as not being emulators: “Wine is not an emulator” “Rosetta isn't an emulator”, “x86 compatibility mode is not an emulator”, “virtualization isn't emulation”, and so on.

And even the starting comment on that thread seems to abide by this definition, as it complains about some (imaginary) emulation overhead when using Wine.

Languages changes overtime as usages evolve: when 80286 was released, the French word «baiser» still meant “to kiss” for most people, now it means “to fuck”.

Every new user seems to think Wine is an emulator, and plenty still after, so I don't believe it's out of fashion. If they don't, it's only because someone tried to make them feel dumb about it with the WINE acronym, which seems to exist because so many people call it an emulator. Maybe if that many people are mistaken, they're actually right.

I especially don't know who's calling Rosetta 2 "not an emulator," given that it's software-emulating x86 arch and actually comes with a noticeable slowdown, not that emulators need to have big overhead.

> Every new user seems to think Wine is an emulator

Most new linux users think that Linux=Ubuntu, does that make it correct? Beginners comes with misconceptions and are then being corrected during their learning process, that's how it works.

> Maybe if that many people are mistaken, they're actually right.

This argument is fabulous, it's like fractally broken, let's have a little bit of fun with it:

I'm pretty sure Wine is niche enough that there's more flat-earthers on this planet than people believing wine to be an emulator, does that number makes them right?

And how about the other people, the majority who know Wine isn't an emulator, would you say “maybe if that many people are correct they're actually wrong”?

> I especially don't know who's calling Rosetta 2 "not an emulator,"

Well, Apple.

You're correct though that Rosetta is arguably an emulator (except, a really sophisticated one, with hardware support, to makes it fast enough) unlike all the other (that interestingly enough you don't address) but if you read my comment again you'll see no contradiction (hint: the key word in that sentence is “market”).

Yes, those people are writing hardware emulators. Doesn't mean they're the only "real" kind.

As for my Intel CPU, it isn't pretending to be another kind of CPU. Intel makes a leading implementation of x86. Wine follows Microsoft's Windows implementation and translates to Linux calls, and the entire point is so you can run programs intended for Windows on Linux instead. You can get relative about it, but it's not really, they're clearly different. Either way, doesn't support WINE's acronym.

> Yes, those people are writing hardware emulators. Doesn't mean they're the only "real" kind.

They're the only kind that doesn't involve a super broad definition of what the word “emulation” means (so broad that most computing actually fits in this definition).

> As for my Intel CPU, it isn't pretending to be another kind of CPU.

Until one day you realize that you can run an x86 program on a 64 bit CPU (but fortunately, this isn't done through “emulation” proper either).

> Until one day you realize that you can run an x86 program on a 64 bit CPU (but fortunately, this isn't done through “emulation” proper either).

It's reasonable to call that emulation if there's a separate layer for it translating to/from x86-64, rather than the hardware specifically supporting -32. My CPU isn't doing that cause I'm not running 32-bit software on macOS.

So AMD CPU’s are emulators then?

No they're not.

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