IF EXIST directory does not always work correctly

On windows it is still possible to check if a directory exists in the following way:

if exist C:\WINDOWS\NUL echo C:\WINDOWS exists and is a directory

This does not seem to work on ROS (tested r72073).
(Note that on windows it is not possible to detect a directory this way if the path includes junctions or symbolic links, or if it is quoted).

The recommended way to test for a directory, is to use a backslash at the end. This works in ROS for directories, but it gives a wrong result for files:

if exist c:\freeldr.sys\ echo this should fail

While writing this, I also found out that pagefile.sys cannot be detected on ROS in the following way:

if exist c:\PAGEFILE.SYS echo PAGEFILE.SYS exists on c:\

related:

• http://www.robvanderwoude.com/battech_ifexistfolder.php
• http://code.reactos.org/changelog/reactos?cs=41942