The DIRECTORY command provides 7 different functions depending on the
 qualifiers used.
 Syntax:
    DIRECTORY/COMPRESS <file>
    Compresses one or more directories.
    DIRECTORY/DUMP <file>
    Provides a block level dump of a directory
    DIRECTORY/REBUILD_MFD <device>
    Recovers a corrupted MFD directory (000000.DIR)
    DIRECTORY/RECOVER <file>
    Recovers a corrupted directory
    DIRECTORY/ALIAS <device>
    Searches all directories on the device for alias file entries
    DIRECTORY/EMPTY <device>
    Searches the disk for empty directories.
    DIRECTORY/VERSION=n <device>
    Searches all directories on the device for files which
    have at least n versions.
 The qualifiers /ALIAS, /EMPTY, and /VERSION can be
 combined in one command.
 Other combinations of qualifiers are not possible.
1 – Parameters
file,(@file) The /COMPRESS , /DUMP and /RECOVER qualifier require a directory-file name as a parameter. A logical name or an indirect command file can also be used as a parameter eg.: DIR/COMPRESS @DIR.COM . Thus it is possible to generate a list with SEARCH device/OUTPUT=file and use that file as input to the DIRECTORY command. The list generated by DFU SEARCH will contain the device name in the file specification. If a filelist is used from another source which does not contain the device name, the /DEVICE must be used to append the device name to the file. device The /ALIAS, /EMPTY , /REBUILD_MFD and /VERSION qualifier require a device name as a parameter.
2 – Qualifiers
2.1 /ALIAS
Scan all directories on a disk for alias files.
2.2 /COMPRESS
    Recreates and compresses the directory. Because directories
    are alphabetically sorted files, deleting and entering files
    randomly will create 'holes' in directory files. /COMPRESS
    will remove these holes by rebuilding and truncating the
    directory.
2.3 /DEVICE=device-name
    Append the device name to the directory-file name. Can only be
    used with /COMPRESS or /DUMP
2.4 /DUMP
    Produces a dump of the directory file block by block.
    This command may be usefull for debugging corrupted
    or suspected directories.
2.5 /EMPTY
Scan the disk for empty directories.
2.6 /FILL_FACTOR
    /FILL_FACTOR=percentage
    This qualifier is only valid in combination with /COMPRESS.
    Default behaviour for DFU is to compress a directory as tight
    as possible; this is equivalent to /FILL_FACTOR=100.
    By choosing a lower fill_factor DFU will leave some free
    space in each directory block. /FILL_FACTOR may be between
    50 and 100 %. Caution : choosing a fill_factor lower than
    100% may fail if the directory file is not large enough.
    In that case DFU will signal an error and advise using
    a higher fill_factor.
2.7 /FORMAT
    /FORMAT=format_string
    Used with /VERSION and /OUTPUT. Create an output file using
    the format as described in formatstring. The format string
    MUST contains the !AS directive; DFU fills in the resultant
    file there. Example :
 	DFU> DIR/VERSION=3/OUT=P.COM/FORMAT="$purge !AS"
2.8 /OUTPUT
    /OUTPUT=filename
    This qualifier redirects the output from DFU to an output file.
2.9 /REBUILD_MFD
    /REBUILD_MFD
    Rebuilds the disk's 000000.DIR directory and makes sure
    the file backlinks to itself.
2.10 /RECOVER
    /RECOVER
    Rebuilds a corrupted directory file. Do not use this
    command on critical (system)directories!
2.11 /STATISTICS
    /STATISTICS
    /NOSTATISTICS  (default)
    Controls whether CPU and I/O consumption of the
    command are shown.
2.12 /TEST
    This qualifier can be used only in conjunction with /COMPRESS.
    When /TEST is specified DFU will show the results of a
    directory compression without actually performing a compress
    operation.
2.13 /TRUNCATE
    /TRUNCATE(=n)
    This qualifier is only valid in combination with /COMPRESS.
    After compressing a directory DFU will NOT truncate the
    empty blocks at the end of the directory , unless /TRUNCATE
    is specified. A number 'n' may be specified to let DFU truncate
    no further than 'n' blocks. ('n' will be rounded up to a
    multiple of the disks cluster size.) Example: a 60 block
    directory A.DIR can be compressed to 20 blocks. The results are:
 	DIR/COMPRESS 	            -->  A.DIR size 20/60 blocks.
 	DIR/COMPRESS/TRUNCATE       -->  A.DIR size 20/20 blocks.
 	DIR/COMPRESS/TRUNCATE=40    -->  A.DIR size 20/40 blocks.
2.14 /VERSION
    /VERSION=n
    Scan all directories of a given device for files which have
    at least 'n' versions.