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> In case you weren't aware Wine is not an emulator, it is a compatibility layer. Ehhh. I know it’s in the name, but I feel like the significance is debatable.

> In case you weren't aware Wine is not an emulator, it is a compatibility layer. Ehhh. I know it’s in the name, but I feel like the significance is debatable. It’s not a CPU emulator, true. It is emulating calls, which is emulation of a sort.

udp 4y ago
It’s a reimplementation of the APIs rather than an emulation. Same as how Linux reimplemented UNIX APIs, but it’s not a UNIX emulator.
- messe 4y ago
  That's still emulating the underlying API, and accepted usage of the word. Much like the FreeBSD linux emulator translates linux syscalls into FreeBSD ones.
  - Spivak 4y ago
    Is any compatibility shim an emulator?
    - entropicdrifter 4y ago
      This is all really just a philosophical question as to how you choose to use the word. It's the same as people who get in a twist over every game with procedural generation and permadeath being called a "Roguelike" even though that particular subgenre used to be more specific to turn-based RPGs with procedural generation, permadeath and total loss of all progress between runs. People who came into using the term earlier tend to think of it more narrowly, but colloquial use of the term has drifted to mean something more generic, e.g. "emulation" used to mean "making one piece of hardware pretend to be another", but now can sometimes just mean, "when one thing acts like another at all".
      - Wowfunhappy 4y ago
        In this case, however, the term "to emulate" predates microprocessors, so it clearly can't have ever referred exclusively to ISA translation! "Emulator" might be a more recent term—it would be interesting to see the etymology, actually—but it's reasonable to conclude that anything which "emulates" must be an "emulator". (Also, OP didn't actually use the word "emulator".) Edit: Nope, the word "emulator" dates back to at least the 1800s (although it has certainly grown in usage more recently): https://books.google.com/ngrams/graph?content=emulator&year_start=1800&year_end=2019&corpus=26&smoothing=3&direct_url=t1%3B%2Cemulator%3B%2Cc0#t1%3B%2Cemulator%3B%2Cc0 https://books.google.com/ngrams/graph?content=emulator&year_...
        entropicdrifter 4y ago
        Huh, what happened in 1984/85 that made "emulator" so much more popular a term than before? Aha! It was Apple's Macintosh release, which included an Apple II emulator built-in: https://books.google.com/books?id=Ti8EAAAAMBAJ&pg=PA13&lpg=PA13&dq=%22ii+in+a+mac%22+emulator&source=bl&ots=KZZfp6Xuwl&sig=AisRDIfiQ4S3lkcUyfahfVnt-Pc&hl=en&ei=RzgUTOnFJ4SClAfl_eWIDA&sa=X&oi=book_result&ct=result#v=onepage&q=%22ii%20in%20a%20mac%22%20emulator&f=false https://books.google.com/books?id=Ti8EAAAAMBAJ&pg=PA13&lpg=P...
        Wowfunhappy 4y ago
        I don't think it could have been just that? Usage peaked in 1984, but it rose quite steadily starting in the early 70s. I do assume most of the increase in usage was related to computers/software, however. The timing is right.
  - extropy 4y ago
    By that logic any modern windows is an emulator of win32, since that is not a kernel API but a user space library "emulating" it. Exactly the same way as wine. Wine does not translate the calls, it for most part actually implements the underlying logic. Win32 is just a bunch of shared libraries: https://en.wikipedia.org/wiki/Microsoft_Windows_library_files#KERNEL32.DLL https://en.wikipedia.org/wiki/Microsoft_Windows_library_file...
    - deleted 4y ago
      [deleted]
    - messe 4y ago
      You're exactly right, and the Wine project agrees. > That said, Wine can be thought of as a Windows emulator in much the same way that Windows Vista can be thought of as a Windows XP emulator: both allow you to run the same applications by translating system calls in much the same way. Setting Wine to mimic Windows XP is not much different from setting Vista to launch an application in XP compatibility mode. > [...] > "Wine is not just an emulator" is more accurate. Thinking of Wine as just an emulator is really forgetting about the other things it is. Wine's "emulator" is really just a binary loader that allows Windows applications to interface with the Wine API replacement.
  - littlestymaar 4y ago
    Saying wine is an emulator is as wrong as saying docker (on linux) is a virual machine, even though you could say it allows you to run a “virtual environment” in the same hand-wavy way you're using the word “emulating” in your sentence.
    - messe 4y ago
      How is it hand-wavy? > emulate (transitive verb) > To imitate the function of (another system), as by modifications to hardware or software that allow the imitating system to accept the same data, execute the same programs, and achieve the same results as the imitated system. It's the exact same way its used by FreeBSD for its linux compatibility layer. It's the same way that Wine even uses in their FAQ. > That said, Wine can be thought of as a Windows emulator in much the same way that Windows Vista can be thought of as a Windows XP emulator: both allow you to run the same applications by translating system calls in much the same way. Setting Wine to mimic Windows XP is not much different from setting Vista to launch an application in XP compatibility mode. > [...] > "Wine is not just an emulator" is more accurate. Thinking of Wine as just an emulator is really forgetting about the other things it is. Wine's "emulator" is really just a binary loader that allows Windows applications to interface with the Wine API replacement.
      - littlestymaar 4y ago
        The problem with this definition is that it's so broad it encompasses many many things that are never talked about as “emulators”. By this definition, Docker is an emulator, a VM is an emulator, an x86_64 CPU is an emulator (because it “emulates“, in the broadest sense, x86), a C compiler is an emulator (“emulating” the PDP-11 on modern hardware), etc. Even your own quote reveals the issue: > > That said, Wine can be thought of as a Windows emulator in much the same way that Windows Vista can be thought of as a Windows XP emulator Yet nobody talks about the latest Windows as being an emulator for older windows … In short, this definition is akin to defining humans as “bipeds without feather”, we definitely fit this definition but it's way too broad to be useful.
xeromal 4y ago
I think most people interpret emulation as CPU emulation, not a compatibility layer otherwise .NET core is probably just one fat emulator.
- deelowe 4y ago
  I hate to break to to those people, but that approach to emulation is only used for very old systems. Once you get into 32 bit, it’s mostly HLE.
lenkite 4y ago
By that definition, wouldn't the whole of POSIX simply be an "emulation layer" ;-)
kmeisthax 4y ago
Usually when you say "emulator" people think there's an inherent performance hit because of a fetch-decode-execute interpreter loop somewhere. Reimplementations of things don't have that performance hit even though they are lumped under the same umbrella as actual interpreters and recompilers. Related note: if WINE is an emulator why isn't Linux or GNU? They both reimplement parts of UNIX, which was even more proprietary than Windows is today.
- btdmaster 4y ago
  UNIX source code, at least for the original versions, was released in 2002: https://slashdot.org/story/02/01/24/0146248/caldera-releases-original-unices-under-bsd-license https://slashdot.org/story/02/01/24/0146248/caldera-releases...
- Wowfunhappy 4y ago
  > If WINE is an emulator why isn't Linux or GNU? I mean, it depends on the context. I don't think it would be wrong to say that Linux "emulates a UNIX environment" or some such, which is closer to what OP actually wrote about Wine. You've probably used a "terminal emulator" at some point today. ;)
  - nmz 4y ago
    It does have a terminal emulator, but you can also drop to a tty.
- shadowgovt 4y ago
  Nowadays it's emulators all the way down. On most of these architectures the software eventually executes as x86 machine code, and the distance between x86 machine code and the actual processes inside a modern CPU implementing the x86 code set is so vast you can call a modern CPU an "x86 emulator built in hardware."
  - broodbucket 4y ago
    Entirely accurate. Also makes it easier to have a firmware/microcode update that gives you a new instruction.

udp 4y ago

It’s a reimplementation of the APIs rather than an emulation. Same as how Linux reimplemented UNIX APIs, but it’s not a UNIX emulator.

messe 4y ago
That's still emulating the underlying API, and accepted usage of the word. Much like the FreeBSD linux emulator translates linux syscalls into FreeBSD ones.
- Spivak 4y ago
  Is any compatibility shim an emulator?
  - entropicdrifter 4y ago
    This is all really just a philosophical question as to how you choose to use the word. It's the same as people who get in a twist over every game with procedural generation and permadeath being called a "Roguelike" even though that particular subgenre used to be more specific to turn-based RPGs with procedural generation, permadeath and total loss of all progress between runs. People who came into using the term earlier tend to think of it more narrowly, but colloquial use of the term has drifted to mean something more generic, e.g. "emulation" used to mean "making one piece of hardware pretend to be another", but now can sometimes just mean, "when one thing acts like another at all".
    - Wowfunhappy 4y ago
      In this case, however, the term "to emulate" predates microprocessors, so it clearly can't have ever referred exclusively to ISA translation! "Emulator" might be a more recent term—it would be interesting to see the etymology, actually—but it's reasonable to conclude that anything which "emulates" must be an "emulator". (Also, OP didn't actually use the word "emulator".) Edit: Nope, the word "emulator" dates back to at least the 1800s (although it has certainly grown in usage more recently): https://books.google.com/ngrams/graph?content=emulator&year_start=1800&year_end=2019&corpus=26&smoothing=3&direct_url=t1%3B%2Cemulator%3B%2Cc0#t1%3B%2Cemulator%3B%2Cc0 https://books.google.com/ngrams/graph?content=emulator&year_...
      - entropicdrifter 4y ago
        Huh, what happened in 1984/85 that made "emulator" so much more popular a term than before? Aha! It was Apple's Macintosh release, which included an Apple II emulator built-in: https://books.google.com/books?id=Ti8EAAAAMBAJ&pg=PA13&lpg=PA13&dq=%22ii+in+a+mac%22+emulator&source=bl&ots=KZZfp6Xuwl&sig=AisRDIfiQ4S3lkcUyfahfVnt-Pc&hl=en&ei=RzgUTOnFJ4SClAfl_eWIDA&sa=X&oi=book_result&ct=result#v=onepage&q=%22ii%20in%20a%20mac%22%20emulator&f=false https://books.google.com/books?id=Ti8EAAAAMBAJ&pg=PA13&lpg=P...
        Wowfunhappy 4y ago
        I don't think it could have been just that? Usage peaked in 1984, but it rose quite steadily starting in the early 70s. I do assume most of the increase in usage was related to computers/software, however. The timing is right.
- extropy 4y ago
  By that logic any modern windows is an emulator of win32, since that is not a kernel API but a user space library "emulating" it. Exactly the same way as wine. Wine does not translate the calls, it for most part actually implements the underlying logic. Win32 is just a bunch of shared libraries: https://en.wikipedia.org/wiki/Microsoft_Windows_library_files#KERNEL32.DLL https://en.wikipedia.org/wiki/Microsoft_Windows_library_file...
  - deleted 4y ago
    [deleted]
  - messe 4y ago
    You're exactly right, and the Wine project agrees. > That said, Wine can be thought of as a Windows emulator in much the same way that Windows Vista can be thought of as a Windows XP emulator: both allow you to run the same applications by translating system calls in much the same way. Setting Wine to mimic Windows XP is not much different from setting Vista to launch an application in XP compatibility mode. > [...] > "Wine is not just an emulator" is more accurate. Thinking of Wine as just an emulator is really forgetting about the other things it is. Wine's "emulator" is really just a binary loader that allows Windows applications to interface with the Wine API replacement.
- littlestymaar 4y ago
  Saying wine is an emulator is as wrong as saying docker (on linux) is a virual machine, even though you could say it allows you to run a “virtual environment” in the same hand-wavy way you're using the word “emulating” in your sentence.
  - messe 4y ago
    How is it hand-wavy? > emulate (transitive verb) > To imitate the function of (another system), as by modifications to hardware or software that allow the imitating system to accept the same data, execute the same programs, and achieve the same results as the imitated system. It's the exact same way its used by FreeBSD for its linux compatibility layer. It's the same way that Wine even uses in their FAQ. > That said, Wine can be thought of as a Windows emulator in much the same way that Windows Vista can be thought of as a Windows XP emulator: both allow you to run the same applications by translating system calls in much the same way. Setting Wine to mimic Windows XP is not much different from setting Vista to launch an application in XP compatibility mode. > [...] > "Wine is not just an emulator" is more accurate. Thinking of Wine as just an emulator is really forgetting about the other things it is. Wine's "emulator" is really just a binary loader that allows Windows applications to interface with the Wine API replacement.
    - littlestymaar 4y ago
      The problem with this definition is that it's so broad it encompasses many many things that are never talked about as “emulators”. By this definition, Docker is an emulator, a VM is an emulator, an x86_64 CPU is an emulator (because it “emulates“, in the broadest sense, x86), a C compiler is an emulator (“emulating” the PDP-11 on modern hardware), etc. Even your own quote reveals the issue: > > That said, Wine can be thought of as a Windows emulator in much the same way that Windows Vista can be thought of as a Windows XP emulator Yet nobody talks about the latest Windows as being an emulator for older windows … In short, this definition is akin to defining humans as “bipeds without feather”, we definitely fit this definition but it's way too broad to be useful.

xeromal 4y ago

I think most people interpret emulation as CPU emulation, not a compatibility layer otherwise .NET core is probably just one fat emulator.

deelowe 4y ago
I hate to break to to those people, but that approach to emulation is only used for very old systems. Once you get into 32 bit, it’s mostly HLE.

lenkite 4y ago

By that definition, wouldn't the whole of POSIX simply be an "emulation layer" ;-)

kmeisthax 4y ago

Usually when you say "emulator" people think there's an inherent performance hit because of a fetch-decode-execute interpreter loop somewhere. Reimplementations of things don't have that performance hit even though they are lumped under the same umbrella as actual interpreters and recompilers. Related note: if WINE is an emulator why isn't Linux or GNU? They both reimplement parts of UNIX, which was even more proprietary than Windows is today.

btdmaster 4y ago
UNIX source code, at least for the original versions, was released in 2002: https://slashdot.org/story/02/01/24/0146248/caldera-releases-original-unices-under-bsd-license https://slashdot.org/story/02/01/24/0146248/caldera-releases...
Wowfunhappy 4y ago
> If WINE is an emulator why isn't Linux or GNU? I mean, it depends on the context. I don't think it would be wrong to say that Linux "emulates a UNIX environment" or some such, which is closer to what OP actually wrote about Wine. You've probably used a "terminal emulator" at some point today. ;)
- nmz 4y ago
  It does have a terminal emulator, but you can also drop to a tty.
shadowgovt 4y ago
Nowadays it's emulators all the way down. On most of these architectures the software eventually executes as x86 machine code, and the distance between x86 machine code and the actual processes inside a modern CPU implementing the x86 code set is so vast you can call a modern CPU an "x86 emulator built in hardware."
- broodbucket 4y ago
  Entirely accurate. Also makes it easier to have a firmware/microcode update that gives you a new instruction.