Re: whats the diff between "command.com" and "cmd.exe" ? does xp home have it or just xp pro ?

From: Wesley Vogel (123WVogel955_at_comcast.net)
Date: 11/29/04 

Date: Mon, 29 Nov 2004 11:15:57 -0700

Hi R. C.,

I pretty much agree with everything you've stated.

I don't believe that I qualify as an expert. But I had to get my 2¢ worth
in. :-)
===

For a good example of how COMMAND.COM runs CMD.EXE.

Have a look here >>>

The Windows NT Command Shell
http://www.microsoft.com/technet/prodtechnol/winntas/deploy/shellscr.mspx

Scroll down to (or Ctrl + F, for COMMAND.COM runs CMD.EXE) >>>

CMD.EXE and COMMAND.COM
[[You can see COMMAND.COM automatically execute a 32-bit CMD.EXE shell by
using the Windows NT Task Manager application. Follow this procedure:]]

[[This simple experiment shows that every command entered for execution,
regardless of the shell used, is ultimately executed by CMD.EXE, the Windows
NT command shell.]]
===

Also...

NTVDM.EXE is the program that creates the virtual MS-DOS 16-bit environment
and is a Win32 (32-bit) program. NTVDM.EXE = NT Virtual DOS Machine.

We have to remember that Windows XP is really Windows NT 5.1.

When you open command.com, Task Manager shows it as MS-DOS Prompt under
the Applications tab.

In Task Manager, under Applications tab, right click MS-DOS Prompt and
select: Go To Process.

Task Manager will then switch to the Processes tab with ntvdm.exe
highlighted.
===

One of the many ways I seem to learn about things is by posting about
something I think I know about. This usually elicits posts with even more
info about that subject. :-D 

-- 
Hope this helps.  Let us know.
Wes
In news:%23vI6wqi1EHA.2804@TK2MSFTNGP15.phx.gbl,
R. C. White <rc@corridor.net> hunted and pecked:
> Hi, Wes.
>
>> Using command.com will open cmd.exe.
>
> I'm not sure what this means, but as I said in my earlier post:
>
>>> Either CMD.EXE or COMMAND.COM can be used to open a "DOS" window
>
> and
>
>>> When in the CMD.EXE window, type "command" (no quotes) to open the
>>> 16-bit emulator inside the 32-bit; in the COMMAND.COM window, type
>>> "cmd" to open the 32-bit version inside.
>
> CMD.EXE identifies itself in its "DOS" window as:
> Microsoft Windows XP [Version 5.1.2600]
>
> COMMAND.COM identifies itself as:
> Microsoft(R) Windows DOS
>
> Their claimed copyright dates are 1985-2001 for CMD.EXE, 1990-2001 for
> COMMAND.COM.
>
> I'm an accountant (and retired), not a techie, so I'm not sure what
> goes on down in the guts of the OS or the NTVDM.  My comments were
> not meant for experts, but for readers in these newsgroups
> (windowsxp.basics, .general and .newusers) who might have been
> confused by the comment, "CMD.EXE...it's not a DOS window", in
> response to the questions in the Subject line.  It's easy to test
> what I've posted.  EITHER of them will open a "DOS" window; neither
> of them is true MS-DOS; either can be opened inside the other; and
> they both work the same in WinXP Home and WinXP Pro.
>
> RC
> --
> R. C. White, CPA
> San Marcos, TX
> rc@corridor.net
> Microsoft Windows MVP
>
> "Wesley Vogel" <123WVogel955@comcast.net> wrote in message
> news:OrDEhu%230EHA.3840@tk2msftngp13.phx.gbl...
>> Using command.com will open cmd.exe.
>>
>> [[When a command is entered for execution by this shell
>> {command.com}, it does not actually execute it. Instead, it packages
>> the command text and sends it to a 32-bit CMD.EXE command shell for
>> execution.]]
>>
>> --
>> Hope this helps.  Let us know.
>> Wes
>>
>> In news:%23fOb8iP0EHA.3808@tk2msftngp13.phx.gbl,
>> R. C. White <rc@corridor.net> hunted and pecked:
>>> Hi, Thread.
>>>
>>> I hate to resurrect this two-month-old thread, but I disagree some
>>> of the comments in the parts of the thread that have not scrolled
>>> off. Perhaps it was cleared up in posts that I can't see now; if
>>> so, I apologize for butting in.
>>>
>>>> CMD.EXE is the Windows NT command line interface, its not a DOS
>>>> window.
>>>
>>> Either CMD.EXE or COMMAND.COM can be used to open a "DOS" window
>>> ("DOS" in quotes to emphasize that it is an emulator, not true
>>> MS-DOS).  To see for yourself, click Start | Run (or just press
>>> Win+R) and type in the Open box: cmd, then press Enter.  You should
>>> see a "DOS" window open.  Then click Start | Run again and enter:
>>> Command.  You should see a second "DOS" window open.  You can
>>> Alt+Tab between them to see the differences, or resize them to see
>>> both "DOS" windows at once and compare them.
>>>
>>> CMD.EXE is the 32-bit emulator; COMMAND.COM is the 16-bit version.
>>> When in the CMD.EXE window, type "command" (no quotes) to open the
>>> 16-bit emulator inside the 32-bit; in the COMMAND.COM window, type
>>> "cmd" to open the 32-bit version inside.  In either case, Exit
>>> returns you to the parent shell; Exit from the top-level parent
>>> closes the window.  Most MS-DOS commands work in either window,
>>> although there are some differences.  Type Help in either one to see
>>> a list of commands.
>>>
>>> And, yes, this works the same for WinXP Home Edition and
>>> Professional.
>>>
>>> RC
>>>
>>> "S.Sengupta" <ssengupta_@msn.com> wrote in message
>>> news:uMPySOYoEHA.3728@TK2MSFTNGP09.phx.gbl...
>>>> CMD.EXE is the Windows NT command line interface, its not a DOS
>>>> window. Whereas,COMMAND.COM is a 16-bit DOS application which is
>>>> used for older DOS compatibility and actually runs inside the NTVDM
>>>> (NT Virtual DOS Machine) due to its 16-bit nature.
>>>>
>>>> regards,
>>>> ssg MS-MVP
>>>> pronetworks.org
>>>>
>>>>
>>>> *ProteanThread* wrote:
>>>>
>>>>> and does "command.com" pose a risk (as some viruses that attacked
>>>>> older win3x/msdos and win9x machines attached themselves to
>>>>> command.com) ?
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