From: "Paul G." <pgarceau AT attbi DOT com>
Organization: Paul G.
To: "Mingw users list" <mingw-users AT lists DOT sourceforge DOT net>,
   "DJGPP List" <djgpp AT delorie DOT com>
Date: Mon, 23 Sep 2002 17:57:56 -0700
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Subject: RE: [Mingw-users] command.com vs. cmd.exe
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On 23 Sep 2002 at 10:53, Andrew Stadt wrote:

[snip]

> >	Umm...as others have noted, I do not believe there is such
> >a thing as
> >"command.com" under Win2k or XP.
> 
> On two of my machines with W2k on them, there is a command.com.

	Considering that the Win2k OS is thought of (for MS software revison releases) as 
"NT5", it does not surprise me that "command.com" exists under Win2k.

	Since it does, according to the poster of this reply, exist, then it is invoked in the 
same way that command.com is invoked under NT4 (and possibly even NT3).

>  While I
> haven't been able to figure out the exact trigger for it to load/unload, I
> did notice the following:
> 1.  %comspec% is set to cmd.exe, and cmd.exe is loaded whenever you open a
> command prompt, or call 'system(...)' from within an application.
> 2.  .cmd & .bat files both seem to processes by cmd.exe (e.g. they will work
> with out command.com being present) - provided that they do not attempt to
> call a dos based application.
> 3.  command.com seems to be loaded whenever you attempt to run a 16 bit dos
> application, it will attempt to reload itself (if necessary) after the
> program exits, only to then exit back to cmd.exe

	You can also invoke command.com from the cmd.exe prompt by simply typing 
"command".  This immediately opens a new (16bit) command prompt (comand line 
processor) shell within the cmd.exe (32bit command line processor) shell.

> 
> According to some text in the config.nt file: When you return to the command
> prompt from a TSR or while running an MS-DOS-based application, Windows runs
> command.com. This allows the TSR to remain active. To run cmd.exe, the
> Windows command prompt, rather than command.com, abd the ntcmdprompt to
> config.nt or other startup file.
> 
> I can't speak for XP.

	Paul G.