
 > Is there any way us non-programmer types could test for the
 > presence of 4DOS
 > from a batch file? Something that would return an errorlevel
 > different from one
 > that would be returned by conventional DOS?

=====================
if %@eval[2*2] == *@eval[2+2] goto 4dos_loaded
....
commands to be executed under command.com only
.....
goto end
:4dos_loaded
...
commands to be executed under 4dos only
....
:end
====================

Under 4dos the expressions on either side of the "==" evaluate to 4 so 
the batch will branch to :4dos_loaded.

Command.com merely tests to see if the strings on either side of the 
"==" are identical and since they are not, no branch takes place.

