DIRECTORY EXISTENCE TESTS

As stated in the CONDITION topic, EXIST always fails for directory names, but
by using a device name, an IF test can determine whether X (which may be an 
environment variable, replaceable parameter, or explicit FOR loop-variable) is 
a file or some type of disk name or directory. 

        CONDITION:	TRUE implies that X is:
    IF EXIST X		a file
    IF EXIST XNUL	a disk name, a non-existent disk name, root, a 
			pathname with trailing \, or part of filename that 
			ends in "NUL".
    IF EXIST X.\NUL	a disk name, root, or a pathname (except ..), with or 
			without a trailing \
    IF EXIST X..\NUL	a disk name, pathname, or possible pathname ending in \
    IF EXIST X\.\NUL	a disk name, or pathname (with or without trailing \)
    IF EXIST X\..\NUL	a pathname, or possible pathname (with or without 
    	    		trailing \)

Any device name can be used. Root (\) is not a pathname that ends in \.
