1    /ALIAS

    Scan all directories on a disk for alias files.

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.

3    /DEVICE=device-name

    Append the device name to the directory-file name. Can only be
    used with /COMPRESS or /DUMP

4    /DUMP

    Produces a dump of the directory file block by block.
    This command may be usefull for debugging corrupted
    or suspected directories.

5    /EMPTY

    Scan the disk for empty directories.

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.

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"

8    /OUTPUT

    /OUTPUT=filename

    This qualifier redirects the output from DFU to an output file.

9    /REBUILD_MFD

    /REBUILD_MFD

    Rebuilds the disk's 000000.DIR directory and makes sure
    the file backlinks to itself.

10    /RECOVER

    /RECOVER

    Rebuilds a corrupted directory file. Do not use this
    command on critical (system)directories!

11    /STATISTICS

    /STATISTICS
    /NOSTATISTICS  (default)

    Controls whether CPU and I/O consumption of the
    command are shown.

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.

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.

14    /VERSION

    /VERSION=n

    Scan all directories of a given device for files which have
    at least 'n' versions.