Am 23.01.2014 22:28, schrieb Orchid Win7 v1:
> On 23/01/2014 03:20 PM, Warp wrote:

>> There are many hurdles that you'll encounter. Firstly, you'll need a
>> hard drive that's small and old enough that MS-DOS will actually be able
>> to use it.
>
> I suspect so long as it isn't native 4K sectors, it'll just be reported
> as 2GB.

Bwahaha! Dream on :-P

I might be wrong, but I'd suspect you'll get anything from 2GB down to 
-2GB, depending on whatever value the result overflows to.

>> There are also probably many problems you will encounter
>> due to the fact that your CPU is so damn fast.
>
> Hell yes!

Indeed. IIRC even in the times of the 386DX-50, programs written in 
Turbo Pascal would already occasionally to crash with a division by zero 
right at the start, because in order to calibrate the delay() loop the 
runtime library would run the loop N times, figure out that it took 0 
seconds, and conclude that for 1 second it would need to run the loop 
N/0 times... Whoops!

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>>> There are many hurdles that you'll encounter. Firstly, you'll need a
>>> hard drive that's small and old enough that MS-DOS will actually be able
>>> to use it.
>>
>> I suspect so long as it isn't native 4K sectors, it'll just be reported
>> as 2GB.
>
> Bwahaha! Dream on :-P
>
> I might be wrong, but I'd suspect you'll get anything from 2GB down to
> -2GB, depending on whatever value the result overflows to.

And I think *you* will find that drives larger than 2GB report 
themselves using a different BIOS API.

>>> There are also probably many problems you will encounter
>>> due to the fact that your CPU is so damn fast.
>>
>> Hell yes!
>
> Indeed. IIRC even in the times of the 386DX-50, programs written in
> Turbo Pascal would already occasionally to crash with a division by zero
> right at the start, because in order to calibrate the delay() loop the
> runtime library would run the loop N times, figure out that it took 0
> seconds, and conclude that for 1 second it would need to run the loop
> N/0 times... Whoops!

OK, well I've never seen *that*... I have seen plenty of PCs with a 
"turbo" button though.

It was there for a reason.

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>> The thing is, nobody runs MS-DOS natively anymore, and haven't done so
>> for well over a decade.
>
> I'm pretty sure the in-store management system that John Lewis use is
> still DOS-based. (Whether it's running natively or in some emulation
> layer is another matter...)

http://en.wikipedia.org/wiki/MSDOS

"As of 2011, MS-DOS is still used in some enterprises to run legacy 
applications, such as this US Navy food service management system."

It is unclear whether this is with or without emulation, however. And 
they could just be running this stuff on really ancient hardware. (When 
I left my previous company, we still had a box in storage with Windows 
98 installed on it. Mercifully, I *never* needed to power it up!)

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>
> Oh I don't know... It'll probably work.
>
>> There are many hurdles that you'll encounter. Firstly, you'll need a
>> hard drive that's small and old enough that MS-DOS will actually be able
>> to use it.
>
> I suspect so long as it isn't native 4K sectors, it'll just be reported
> as 2GB.

No.  The boot drive had to have a primary partition that is less than 
2GB, and fits entirely below cylinder 1023 or else DOS won't understand 
it.  You also need a special driver that loads before IO.SYS in order to 
fake the number of heads and cylinders because it doesn't understand LBA 
mode.  This has been the case as far back as drives that had more than 
1GB of space (Anyone remember OnTrack Disk Manager?), since it usually 
meant more than 1024 cylinders, as you couldn't fit more than 2 platters 
in a regular drive bay.

>> So why is the PC architecture dragging all the useless stuff for MS-DOS
>> compatibility, when nobody's running MS-DOS anyway?
>
> No idea. Presumably because it would mean changing stuff?

You can rest assured that somewhere, there's a nuclear reactor or a 
stock-exchange trading application, or an airline flight scheduler or 
something of the sort that still relies on a DOS based controller, ans 
as long as this exists, no hardware maker is going to risk stopping 
support for it for fear of losing business.

Heck, I just saw today that IBM still officially releases JREs of its 
own flavor of Java for OS/2 Warp.  There mu$t be a good rea$on for it.


-- 
/*Francois Labreque*/#local a=x+y;#local b=x+a;#local c=a+b;#macro P(F//
/*    flabreque    */L)polygon{5,F,F+z,L+z,L,F pigment{rgb 9}}#end union
/*        @        */{P(0,a)P(a,b)P(b,c)P(2*a,2*b)P(2*b,b+c)P(b+c,<2,3>)
/*   gmail.com     */}camera{orthographic location<6,1.25,-6>look_at a }

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> On 22/01/2014 1:40 AM, Francois Labreque wrote:
>> not quite, but...
>>
>> Ever since I tried to install the latest Blender, whenever I boot my PC,
>> I get the system32 folder that opens.  I suppose there's a registry
>> entry somewhere that got created improperly and instead of trying to
>> load "C:\Windows\System32\whatchamacallit.dll" or
>> "%SYSTEM_ROOT%\System32\foobar.exe" it simply loads
>> "C:\Windows\System32".
>>
>> How do I find out which one it is?  Regedit's search function is not
>> smart enough to let me search for ( "system32" except when it's
>> "system32\" )
>>
>>
>
> I've seen this before, have a look here:
>
> http://support.microsoft.com/kb/170086
>
> Cheers Dre

This KB article sent me on the proper path...

I paid a closer look at the syntax of the entries in 
HLCU\Software\Microsoft\Windows\CurrentVersion\Run, and bingo.

It was an invalid entry created by the Epson Printer software installer. 
  (Apologies to the Blender Foundation for wrongly acusing them!)

I also found a gazillion entries where rundll32.exe is not using the 
full path, which could lead to very easy trojan horse injections.

ex:
Good:
[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\htmlfile\shell\print\command]
@="\"C:\\WINDOWS\\system32\\rundll32.exe\" 
\"C:\\WINDOWS\\system32\\mshtml.dll\",PrintHTML \"%1\""


Bad:
[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\jpegfile\shell\open\command]
@="rundll32.exe C:\\WINDOWS\\system32\\shimgvw.dll,ImageView_Fullscreen %1"

-- 
/*Francois Labreque*/#local a=x+y;#local b=x+a;#local c=a+b;#macro P(F//
/*    flabreque    */L)polygon{5,F,F+z,L+z,L,F pigment{rgb 9}}#end union
/*        @        */{P(0,a)P(a,b)P(b,c)P(2*a,2*b)P(2*b,b+c)P(b+c,<2,3>)
/*   gmail.com     */}camera{orthographic location<6,1.25,-6>look_at a }

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> The Raspberry Pi didn't exist ten years ago, but now that I think about
> it, that *would* be an interesting target...

Here's a start:

http://www.cl.cam.ac.uk/projects/raspberrypi/tutorials/os/index.html

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