1 DU
 DU (Directory Usage) lists directories and the total number of blocks 
 used and allocated and the total number of files contained within those 
 directories.
 
 DU is considerably faster than DIRECTORY/TOTAL or DIRECTORY/GRAND_TOTAL
 non-trivial disk space hunts, since it works by reading the index file
 directly, not by searching through directories.  Also, it provides single 
 line summaries of each directory matching the given specification, which 
 is more useful than the multi-line summaries given by DIRECTORY/TOTAL.
 
 Execution time is mostly a function of the number of files on the disk.  
 DU processes between 800 and 1000 files per second (a "typical" RA82 
 might contain 10,000 files).
 
 Format:
         $ DU <directory>
2 Parameters
 DU takes only one parameter, the directory name to search.  This can be 
 a wildcard directory specification.  File names are ignored.
 
 If a wildcard is used, the listing will contain one line per directory 
 matching the specification; if there are no wildcards, only one line will 
 show.  
 
 The directory parsing mechanisim will handle most directory syntaxes, 
 including rooted logicals and angle brackets.  PPN-style directory 
 specifications are only supported in for the MFD (ie [0,0]).
2 Qalifiers
/MINIMUM
 /MINIMUM=blocks

 The /MINIMUM qualifier specifies the minimum allocated space a directory 
 (and subdirectories) must occupy to be displayed.  If specified without a 
 value, the default is one block, meaning that empty directories will not 
 appear on the listing.  
/SINCE
 /SINCE=date

 The /SINCE qualifier specifies that only files created or (or modified if 
 used in conjunction with the /MODIFIED qualifier) since the specified 
 date are counted.  The /MINIMUM qualifier is recommended with /SINCE. 
/MODIFIED
 The /MODIFIED flag specifies that the /SINCE=date qualifier use the 
 modified date rather than the creation date when deciding whether to 
 include a file in its statistics.
/OUTPUT
 /OUTPUT=filespec

 The /OUTPUT qualifier directs DU's output to the specified file.
