• Re: New door bundle, Ambr

    From wkitty42@VERT/SESTAR to Dumas Walker on Monday, July 08, 2019 13:38:25
    Re: Re: New door bundle, Ambr
    By: Dumas Walker to Marisag on Sat Mar 23 2019 15:12:01

    You really should not be mixing your architectures like this. I am not sure what trouble that can cause, but I cannot imagine
    that it does not, especially when some of these dependencies it is asking for would require OVERWRITING the 64-bit versions in
    order to be installed (if apt would even let you do that).

    i'm pretty sure this has been sussed since it was 3 months ago but one word... multiarch... it allows both 32bit and 64bit apps to run and keeps the libs separate to that each can load what they need...

    some 64bit folks don't like running multiarch and prefer to stay pure 64bit but then you get some folks that just want their desired programs to work no matter if they are 32bit or 64bit...


    )/\(aldo

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  • From Marisag@VERT/AMIGAC to wkitty42 on Monday, July 08, 2019 13:04:11
    Re: Re: New door bundle, Ambr
    By: wkitty42 to Dumas Walker on Mon Jul 08 2019 13:38:25

    i'm pretty sure this has been sussed since it was 3 months ago but one word... multiarch... it allows both 32bit and 64bit apps to run and keeps the libs separate to that each can load what they need...

    There is nothing stopping you from running 32bit apps on a 64bit linux. For example on Ubuntu you can have both 32bit & 64bit versions of the libraries. I depend on that in a lot of my doors...

    Marisa
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  • From Nightfox@VERT/DIGDIST to Marisag on Monday, July 08, 2019 22:05:25
    Re: Re: New door bundle, Ambr
    By: Marisag to wkitty42 on Mon Jul 08 2019 01:04 pm

    There is nothing stopping you from running 32bit apps on a 64bit linux. For example on Ubuntu you can have both 32bit & 64bit versions of the libraries. I depend on that in a lot of my doors...

    Recently I heard Ubuntu wanted to drop all 32-bit support going forward. Now it sounds like Ubuntu has decided to keep supporting selected 32-bit libraries.

    https://www.omgubuntu.co.uk/2019/06/ubuntu-is-dropping-all-32-bit-support-going -forward
    https://itsfoss.com/ubuntu-19-10-drops-32-bit-support/

    Nightfox

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  • From MRO@VERT/BBSESINF to Nightfox on Tuesday, July 09, 2019 15:53:26
    Re: Re: New door bundle, Ambr
    By: Nightfox to Marisag on Mon Jul 08 2019 10:05 pm

    Re: Re: New door bundle, Ambr
    By: Marisag to wkitty42 on Mon Jul 08 2019 01:04 pm

    There is nothing stopping you from running 32bit apps on a 64bit linux. For example on Ubuntu you can have both 32bit & 64bit versions of the libraries. I depend on that in a lot of my doors...

    Recently I heard Ubuntu wanted to drop all 32-bit support going forward.
    Now it sounds like Ubuntu has decided to keep supporting selected 32-bit libraries.


    that's gonna suck because my irc services are 32bit.

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  • From wkitty42@VERT/SESTAR to Marisag on Tuesday, July 09, 2019 18:51:17
    Re: Re: New door bundle, Ambr
    By: Marisag to wkitty42 on Mon Jul 08 2019 13:04:11

    i'm pretty sure this has been sussed since it was 3 months ago but one
    word... multiarch... it allows both 32bit and 64bit apps to run and keeps
    the libs separate to that each can load what they need...

    There is nothing stopping you from running 32bit apps on a 64bit linux.

    correct... that's what i was pointing out and providing the keyword for ;)

    For example on Ubuntu you can have both 32bit & 64bit versions of the libraries. I depend on that in a lot of my doors...

    same here :)


    )/\(aldo

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  • From Dumas Walker@VERT/CAPCITY2 to WKITTY42 on Tuesday, July 09, 2019 16:55:00
    i'm pretty sure this has been sussed since it was 3 months ago but one word... >ultiarch... it allows both 32bit and 64bit apps to run and keeps the libs separ
    te to that each can load what they need...

    In the case of writing doors, if you are only writing/porting them for use
    on your system is one thing. If you want others to be able to use them,
    then the way that one is distributed will only work for a very limited
    number of people.

    Multiarch or not, I say you are better off installing a 64-bit library that
    has 32-bit compatibility (which I think is what you are really describing)
    than making any attempt at installing an actual 32-bit version that comes complete with a bunch of 32-bit dependencies that will overwrite any 64-bit versions you have installed (if you can figure out how to force apt to
    install them).

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  • From Nightfox@VERT/DIGDIST to MRO on Tuesday, July 09, 2019 18:34:58
    Re: Re: New door bundle, Ambr
    By: MRO to Nightfox on Tue Jul 09 2019 03:53 pm

    Recently I heard Ubuntu wanted to drop all 32-bit support going
    forward. Now it sounds like Ubuntu has decided to keep supporting
    selected 32-bit libraries.

    that's gonna suck because my irc services are 32bit.

    I can kinda understand the decision, but at the same time, I think it would be good to keep supporting 32-bit software. 64-bit Intel-compatible CPUs support it in the hardware, and I think it would make sense for OSes to continue supporting it in the software too. When hardware support for it dies, perhaps OSes can drop it at that point (and we would have to run emulators for it).

    Nightfox

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  • From MRO@VERT/BBSESINF to Nightfox on Wednesday, July 10, 2019 00:41:13
    Re: Re: New door bundle, Ambr
    By: Nightfox to MRO on Tue Jul 09 2019 06:34 pm

    that's gonna suck because my irc services are 32bit.

    I can kinda understand the decision, but at the same time, I think it would be good to keep supporting 32-bit software. 64-bit Intel-compatible CPUs support it in the hardware, and I think it would make sense for OSes to continue supporting it in the software too. When hardware support for it dies, perhaps OSes can drop it at that point (and we would have to run emulators for it).


    perhaps we can have the best of both worlds and have some type of wrapper for 16 bit apps.

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  • From Vk3jed@VERT/FREEWAY to Nightfox on Wednesday, July 10, 2019 16:57:00
    On 07-09-19 18:34, Nightfox wrote to MRO <=-

    I can kinda understand the decision, but at the same time, I think it would be good to keep supporting 32-bit software. 64-bit
    Intel-compatible CPUs support it in the hardware, and I think it would make sense for OSes to continue supporting it in the software too.
    When hardware support for it dies, perhaps OSes can drop it at that
    point (and we would have to run emulators for it).

    I don't see hardware support for 32 bit dying anytime toon. Adterall, modern CPUs can still run 16 bit software, if running in real mode or virtual 8086 mode.


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  • From Nightfox@VERT/DIGDIST to Vk3jed on Wednesday, July 10, 2019 09:36:29
    Re: Re: New door bundle, Ambr
    By: Vk3jed to Nightfox on Wed Jul 10 2019 04:57 pm

    I don't see hardware support for 32 bit dying anytime toon. Adterall, modern CPUs can still run 16 bit software, if running in real mode or virtual 8086 mode.

    I think only 32-bit processors have hardware support for running 16-bit software? 64-bit processors lack that feature and only go back as far as 32-bit software. If you want to run 16-bit software on a 64-bit processor these days, you'll need to use an emulator of some kind.

    Nightfox

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  • From Digital Man@VERT to Nightfox on Wednesday, July 10, 2019 12:45:56
    Re: Re: New door bundle, Ambr
    By: Nightfox to Vk3jed on Wed Jul 10 2019 09:36 am

    Re: Re: New door bundle, Ambr
    By: Vk3jed to Nightfox on Wed Jul 10 2019 04:57 pm

    I don't see hardware support for 32 bit dying anytime toon. Adterall, modern CPUs can still run 16 bit software, if running in real mode or virtual 8086 mode.

    I think only 32-bit processors have hardware support for running 16-bit software? 64-bit processors lack that feature and only go back as far as 32-bit software. If you want to run 16-bit software on a 64-bit processor these days, you'll need to use an emulator of some kind.

    "real mode" is the true 8086 16-bit compatible mode (capable of running PC/MS-DOS) of all x86 CPUs. Processors supporting x86-64 (64-bit x86) still power on in real mode for full backward compatibility, as x86 processors have done since the 80286.
    https://en.wikipedia.org/wiki/X86-64

    digital man

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  • From Nightfox@VERT/DIGDIST to Digital Man on Wednesday, July 10, 2019 17:22:36
    Re: Re: New door bundle, Ambr
    By: Digital Man to Nightfox on Wed Jul 10 2019 12:45 pm

    I think only 32-bit processors have hardware support for running
    16-bit software? 64-bit processors lack that feature and only go back
    as far as 32-bit software. If you want to run 16-bit software on a
    64-bit processor these days, you'll need to use an emulator of some
    kind.

    "real mode" is the true 8086 16-bit compatible mode (capable of running PC/MS-DOS) of all x86 CPUs. Processors supporting x86-64 (64-bit x86) still power on in real mode for full backward compatibility, as x86 processors have done since the 80286.
    https://en.wikipedia.org/wiki/X86-64

    Interesting.. I've always heard that 64-bit x86 processors aren't able to run 16-bit DOS apps, hence the occasional question about DOS doors failing to run on BBSes running in 64-bit Windows. I knew 64-bit Windows doesn't have the 16-bit DOS subsystem, and I thought that was because a 64-bit processor lacks support for 16-bit software, but perhaps that's not true? Come to think of it, my BBS machine is running a 64-bit Linux, and is running a 32-it Windows in a VM, and the 32-bit Windows is able to run DOS doors even though the host processor is a 64-bit processor..

    Nightfox

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  • From Digital Man@VERT to Nightfox on Wednesday, July 10, 2019 18:13:45
    Re: Re: New door bundle, Ambr
    By: Nightfox to Digital Man on Wed Jul 10 2019 05:22 pm

    Re: Re: New door bundle, Ambr
    By: Digital Man to Nightfox on Wed Jul 10 2019 12:45 pm

    I think only 32-bit processors have hardware support for running
    16-bit software? 64-bit processors lack that feature and only go back
    as far as 32-bit software. If you want to run 16-bit software on a
    64-bit processor these days, you'll need to use an emulator of some
    kind.

    "real mode" is the true 8086 16-bit compatible mode (capable of running PC/MS-DOS) of all x86 CPUs. Processors supporting x86-64 (64-bit x86) still power on in real mode for full backward compatibility, as x86 processors have done since the 80286. https://en.wikipedia.org/wiki/X86-64

    Interesting.. I've always heard that 64-bit x86 processors aren't able to run 16-bit DOS apps, hence the occasional question about DOS doors failing to run on BBSes running in 64-bit Windows. I knew 64-bit Windows doesn't have the 16-bit DOS subsystem, and I thought that was because a 64-bit processor lacks support for 16-bit software, but perhaps that's not true?

    If you booted the processer into "real mode", it certainly could run 16-bit software. But that's it. You can't run any 32-bit or 64-bit software in "real mode".

    Come to think of it, my BBS machine is running a 64-bit Linux, and is running a 32-it Windows in a VM, and the 32-bit Windows is able to run DOS doors even though the host processor is a 64-bit processor..

    Running DOS in emulator is different than running DOS in real mode. There's another x86 mode called virtual 86 mode:
    https://en.wikipedia.org/wiki/Virtual_8086_mode

    x64 processors running in 64-bit mode not support virtual 86 mode. That's the issue. So if you run an x64 processor in 32-bit (e.g. running a 32-bit version of Windows), v86 mode is available and NTVDM is supported and works fine.

    digital man

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  • From Vk3jed@VERT/FREEWAY to Nightfox on Thursday, July 11, 2019 08:06:00
    On 07-10-19 09:36, Nightfox wrote to Vk3jed <=-

    I think only 32-bit processors have hardware support for running 16-bit software? 64-bit processors lack that feature and only go back as far
    as 32-bit software. If you want to run 16-bit software on a 64-bit processor these days, you'll need to use an emulator of some kind.

    No, 64 bit processors that (AMD64) support all of the modes that the 32 bit ISA supports, in addition to the 64 bit modes. That's why you can run 16 bit apps under 32 bit Windows on a 64 bit processor, just like you can on a 32 bit processor. It's only when in 64 bit mode that 16 bit apps aren't supported (without some sort of VM or emulation).


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  • From Nightfox@VERT/DIGDIST to Digital Man on Wednesday, July 10, 2019 20:25:21
    Re: Re: New door bundle, Ambr
    By: Digital Man to Nightfox on Wed Jul 10 2019 06:13 pm

    If you booted the processer into "real mode", it certainly could run 16-bit software. But that's it. You can't run any 32-bit or 64-bit software in "real mode".

    Ah, I didn't know that. And it's been a long time since I read about the different x86 processor modes.

    Running DOS in emulator is different than running DOS in real mode. There's another x86 mode called virtual 86 mode: https://en.wikipedia.org/wiki/Virtual_8086_mode

    x64 processors running in 64-bit mode not support virtual 86 mode. That's the issue. So if you run an x64 processor in 32-bit (e.g. running a 32-bit version of Windows), v86 mode is available and NTVDM is supported and works fine.

    Ah, interesting.

    I think it's interesting that Intel and AMD have supported things like this (at least in 32-bit mode) for as long as they have. Nobody really mentions these things when they talk about their latest processor anymore, but I suppose if they were to remove some of these legacy features, they'd have a smaller CPU die, which I suppose may (or may not) reduce power consumption & heat production a little bit.

    Nightfox

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  • From poindexter FORTRAN@VERT/REALITY to Nightfox on Wednesday, July 10, 2019 20:49:16
    Re: Re: New door bundle, Ambr
    By: Nightfox to Digital Man on Wed Jul 10 2019 05:22 pm

    Interesting.. I've always heard that 64-bit x86 processors aren't able to run 16-bit DOS apps, hence the occasional question about DOS doors failing to run on BBSes running in 64-bit Windows.

    it's not the processor, it's the OS. 64 bit Windows OSes don't have the DOSVDM subsystem that allows 32-bit Windows to run 16-bit apps.

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  • From Digital Man@VERT to Nightfox on Wednesday, July 10, 2019 21:56:03
    Re: Re: New door bundle, Ambr
    By: Nightfox to Digital Man on Wed Jul 10 2019 08:25 pm

    Re: Re: New door bundle, Ambr
    By: Digital Man to Nightfox on Wed Jul 10 2019 06:13 pm

    If you booted the processer into "real mode", it certainly could run 16-bit software. But that's it. You can't run any 32-bit or 64-bit software in "real mode".

    Ah, I didn't know that. And it's been a long time since I read about the different x86 processor modes.

    Running DOS in emulator is different than running DOS in real mode. There's another x86 mode called virtual 86 mode: https://en.wikipedia.org/wiki/Virtual_8086_mode

    x64 processors running in 64-bit mode not support virtual 86 mode. That's the issue. So if you run an x64 processor in 32-bit (e.g. running a 32-bit version of Windows), v86 mode is available and NTVDM is supported and works fine.

    Ah, interesting.

    I think it's interesting that Intel and AMD have supported things like this (at least in 32-bit mode) for as long as they have.

    Without, it'd be hard(er) to boostrap all the OSes and tools that use PC hardware. Eventually, I imagine everything will be UEFI and nothing will really need an x86 "real mode", but I think that day is a ways off still.

    Nobody really mentions
    these things when they talk about their latest processor anymore, but I suppose if they were to remove some of these legacy features, they'd have a smaller CPU die, which I suppose may (or may not) reduce power consumption & heat production a little bit.

    So little, it's like nothing/free to include it. All the other enhancements and caches, etc. that have been added to x86 CPUs over the years dwarf the little "real mode" x86 instructions/mode buried in there. No harm leaving it there for those few that do need it.

    digital man

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  • From Digital Man@VERT to poindexter FORTRAN on Wednesday, July 10, 2019 22:05:44
    Re: Re: New door bundle, Ambr
    By: poindexter FORTRAN to Nightfox on Wed Jul 10 2019 08:49 pm

    Re: Re: New door bundle, Ambr
    By: Nightfox to Digital Man on Wed Jul 10 2019 05:22 pm

    Interesting.. I've always heard that 64-bit x86 processors aren't able to run 16-bit DOS apps, hence the occasional question about DOS doors failing to run on BBSes running in 64-bit Windows.

    it's not the processor, it's the OS. 64 bit Windows OSes don't have the DOSVDM subsystem that allows 32-bit Windows to run 16-bit apps.

    Well, it's both. The Windows NTVDM uses x86 "virtual 86" mode to run its DOS subsystem and v86 mode doesn't exist in the 64-bit mode of x86-64 processors (so-called "long mode"). There's really nothing Microsoft could do and I imagine AMD and Intel thought it just wasn't worth the cost/risk to bother trying to support v86 mode in the 64-bit mode of x64 processors.

    From https://en.wikipedia.org/wiki/X86-64:

    Long mode

    Long mode is the architecture's intended primary mode of operation; it is a combination of the processor's native 64-bit mode and a combined 32-bit and 16-bit compatibility mode. It is used by 64-bit operating systems. Under a 64-bit operating system, 64-bit programs run under 64-bit mode, and 32-bit and 16-bit protected mode applications (that do not need to use either real mode or virtual 8086 mode in order to execute at any time) run under compatibility mode. Real-mode programs and programs that use virtual 8086 mode at any time cannot be run in long mode unless those modes are emulated in software.
    However, such programs may be started from an operating system running in long mode on processors supporting VT-x or AMD-V by creating a virtual processor running in the desired mode.

    Legacy mode

    Legacy mode is the mode used by 32-bit or 16-bit "protected mode" operating systems. In this mode, the processor acts like an older x86 processor, and only 16-bit and 32-bit code can be executed. Legacy mode allows for a maximum of 32 bit virtual addressing which limits the virtual address space to 4 GB. 64-bit programs cannot be run from legacy mode.

    ...

    So it looks like special virtualization features could be used in certain X64 processors to create a "virtual processor" would could run in real mode or V86 mode - so maybe there is some hope for a future of NTVDM on 64-bit Windows (?).

    digital man

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  • From Nightfox@VERT/DIGDIST to Vk3jed on Wednesday, July 10, 2019 22:31:41
    Re: Re: New door bundle, Ambr
    By: Vk3jed to Nightfox on Thu Jul 11 2019 08:06 am

    No, 64 bit processors that (AMD64) support all of the modes that the 32 bit ISA supports, in addition to the 64 bit modes. That's why you can run 16 bit apps under 32 bit Windows on a 64 bit processor, just like you can on a 32 bit processor. It's only when in 64 bit mode that 16 bit apps aren't supported (without some sort of VM or emulation).

    Yeah, I'm not sure why I was thinking of it like I was. I knew you can run 16-bit DOS apps on a 32-bit OS on a 64-bit procesor. :)

    Also, Digital Man shared an informative link: https://en.wikipedia.org/wiki/Virtual_8086_mode

    Nightfox

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  • From Nightfox@VERT/DIGDIST to poindexter FORTRAN on Wednesday, July 10, 2019 22:32:12
    Re: Re: New door bundle, Ambr
    By: poindexter FORTRAN to Nightfox on Wed Jul 10 2019 08:49 pm

    Interesting.. I've always heard that 64-bit x86 processors aren't
    able to run 16-bit DOS apps, hence the occasional question about DOS
    doors failing to run on BBSes running in 64-bit Windows.

    it's not the processor, it's the OS. 64 bit Windows OSes don't have the DOSVDM subsystem that allows 32-bit Windows to run 16-bit apps.

    Yeah, I'm not sure what I was thinking.. I've run 32-bit versions of Windows ona 64-bit processor before, for running DOS doors on my BBS..

    Nightfox

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  • From Nightfox@VERT/DIGDIST to Digital Man on Wednesday, July 10, 2019 22:36:48
    Re: Re: New door bundle, Ambr
    By: Digital Man to Nightfox on Wed Jul 10 2019 09:56 pm

    Nobody really mentions
    these things when they talk about their latest processor anymore, but
    I suppose if they were to remove some of these legacy features, they'd
    have a smaller CPU die, which I suppose may (or may not) reduce power
    consumption & heat production a little bit.

    So little, it's like nothing/free to include it. All the other enhancements and caches, etc. that have been added to x86 CPUs over the years dwarf the little "real mode" x86 instructions/mode buried in there. No harm leaving it there for those few that do need it.

    Yeah, they've definitely added a lot of stuff over the years.

    This past week, I've been seeing a lot of articles & videos with benchmarks for AMD's new 3rd-generation Ryzen processors (which were just released on July 7th). The benchmarks look pretty good, and the AMD Ryzen 9 3900X looks particularly impressive. I've been using Intel CPUs for the last 8 years (I had been using AMD for a longtime before that). Competition between Intel and AMD always seems to push them both to produce better processors.

    Nightfox

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  • From Vk3jed@VERT/FREEWAY to Nightfox on Thursday, July 11, 2019 16:19:00
    On 07-10-19 17:22, Nightfox wrote to Digital Man <=-
    https://en.wikipedia.org/wiki/X86-64

    Interesting.. I've always heard that 64-bit x86 processors aren't able
    to run 16-bit DOS apps, hence the occasional question about DOS doors failing to run on BBSes running in 64-bit Windows. I knew 64-bit

    You're confusing 64 bit processors with 64 bit OSs. 64 bit processors can run anything from DOS to the latest 64 bit OSs designed to run on the Intel/AMD architecture. However, 64 bit OSs can't run 16 bit software without some assitance, because the processor doesn't support 16 bit real mode code, when in 64 bit "long mode".

    However, booting a 32 bit OS on a 64 bit processor can run 16 bit apps, because the processor is running in the same 32 bit protected mode or virtual 808s mode, same as any processot since the 80386.

    Windows doesn't have the 16-bit DOS subsystem, and I thought that was because a 64-bit processor lacks support for 16-bit software, but
    perhaps that's not true? Come to think of it, my BBS machine is
    running a 64-bit Linux, and is running a 32-it Windows in a VM, and the 32-bit Windows is able to run DOS doors even though the host processor
    is a 64-bit processor..

    It's to do with the different processor modes.

    From Wikipedia:

    Long mode
    Main article: Long mode

    Long mode is the architecture's intended primary mode of operation; it is a combination of the processor's native 64-bit mode and a combined 32-bit and 16-bit compatibility mode. It is used by 64-bit operating systems. Under a 64-bit operating system, 64-bit programs run under 64-bit mode, and 32-bit and 16-bit protected mode applications (that do not need to use either real mode or virtual 8086 mode in order to execute at any time) run under compatibility mode. Real-mode programs and programs that use virtual 8086 mode at any time cannot be run in long mode unless those modes are emulated in software.[11]:11 However, such programs may be started from an operating system running in long mode on processors supporting VT-x or AMD-V by creating a virtual processor running in the desired mode.

    Since the basic instruction set is the same, there is almost no performance penalty for executing protected mode x86 code. This is unlike Intel's IA-64, where differences in the underlying instruction set mean that running 32-bit code must be done either in emulation of x86 (making the process slower) or with a dedicated x86 coprocessor. However, on the x86-64 platform, many x86 applications could benefit from a 64-bit recompile, due to the additional registers in 64-bit code and guaranteed SSE2-based FPU support, which a compiler can use for optimization. However, applications that regularly handle integers wider than 32 bits, such as cryptographic algorithms, will need a rewrite of the code handling the huge integers in order to take advantage of the 64-bit registers.

    Legacy mode
    Legacy mode is the mode used by 32-bit or 16-bit "protected mode" operating systems[28]. In this mode, the processor acts like an older x86 processor, and only 16-bit and 32-bit code can be executed. Legacy mode allows for a maximum of 32 bit virtual addressing which limits the virtual address space to 4 GB.[11](p14)(p24)(p118) 64-bit programs cannot be run from legacy mode.

    from https://en.wikipedia.org/wiki/X86-64#Operating_modes

    So yeah, it's the real mode DOS code that's the problem. Seems 16 bit protected mode instructions can be used when in long mode (64 bit).


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  • From Nightfox@VERT/DIGDIST to Vk3jed on Thursday, July 11, 2019 09:43:28
    Re: Re: New door bundle, Ambr
    By: Vk3jed to Nightfox on Thu Jul 11 2019 04:19 pm

    You're confusing 64 bit processors with 64 bit OSs. 64 bit processors can run anything from DOS to the latest 64 bit OSs designed to run on the Intel/AMD architecture. However, 64 bit OSs can't run 16 bit software without some assitance, because the processor doesn't support 16 bit real mode code, when in 64 bit "long mode".

    However, booting a 32 bit OS on a 64 bit processor can run 16 bit apps, because the processor is running in the same 32 bit protected mode or virtual 808s mode, same as any processot since the 80386.

    Yeah, I was confusing 64-bit processors with 64-bit OSes. I have even run 32-bit editions of Windows with a 64-bit processor in order to run DOS doors. :P

    Nightfox

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