M ( 1 * C DFU V2.4 !

DFU V2.4

Abstract

7DFU Disk and File Utilities for OpenVMS VAX and Alpha

(Revision Information: This manual supersedes V2.2

Date: August 1996

$Operating System: 1OpenVMS VAX V5.5-2 thru 7.1, Alpha V6.1 thru 7.1

Note: Part of the Freeware CD-ROM

*OpenVMS Freeware for VAX and AXP Systems

:The OpenVMS Freeware CD-ROM contains free software tools 6and utilities to aid software developers in creating 6applications and managing and using OpenVMS systems.

9Many of these tools are popular packages already widely 9known and in use, while others are internally developed 9Digital tools our engineers are making available to our =OpenVMS customers. For example, the OpenVMS Freeware CD-ROM 9includes Bliss-32 for OpenVMS VAX, Bliss-32 for OpenVMS $AXP, and Bliss-64 for OpenVMS AXP.

/Disclaimer on Testing, Quality, and Licensing

8The OpenVMS Freeware for VAX and AXP Systems CD-ROM is 7provided "AS IS" without warranty. Digital imposes no =restrictions on its distribution, nor on the redistribution 8of anything on it. Be aware, however, that some of the 8packages on the CD-ROM may carry restrictions on their <use imposed by the original authors. Therefore, you should =carefully read the documentation accompanying the products.

:Digital Equipment Corporation is providing this software 6free of charge and without warranty. Included in the 6[FREEWARE] directory on this CD are the GNU software 8licenses. Unless otherwise stated in sources or source ;packages, the GNU licenses cover all software supplied on this CD.

=Digital makes no claims about the quality of this software. 3It is provided to the customer as a free service. $

Copyright©August 1996

;

Chapter 1
Introduction

=The Disk and File Utilities (DFU) is a high perfomance tool Imeant as an aid to the system manager who is responsible for monitoring /and maintaining disks, files and directories. IIt makes use of low level I/O features of VMS. As a result a high level @of performance is reached with minimal overhead on the system. CDFU supports all types of disk sets which comply to the VMS ODS-2 standard ?such as volume sets, stripe sets , shadow sets and RAID sets, and combinations of these.

DDFU does NOT work on Spiralog disks. Trying to use DFU on spiralog Fdisks will produce the error "%DFU-E-NOTF11, Device does not have an ODS-2 filesystem" . 6

1.1 Support on DFU

;Although there is no official support on DFU you may send 1questions/remarks/bug-reports to the author via /internet address dorland@utrtsc.enet.dec.com. EA next version of DFU will no longer work on VMS 5.5-2 and VMS 6.0. ;

1.2 General description

@DFU provides the following functions (in alphabetical order) :

DEFRAG : This function allows simple defragmentation of a file or a list of files. F
DELETE : This function allows either a delete by file-id, or a fast delete Hof a complete directory or directory tree with all its subdirectories. 1
DIRECTORY : This function has 6 options :
1. COMPRESS a directory )
2. DUMP a directory block by block 5
3. CREATE a directory with a preallocated size A
4. Search all directories on the disk for files which have multiple versions C
5. Search all directories on the disk for alias file entries B
6. Search all directories on the disk for empty directories
H
REPORT : Generates a file and free space report for a disk. Also a @disk space usage report, based on UIC's or identifiers, can be generated, even *on a disk which has disk quota disabled. I
SEARCH : Look up files on a disk by specific file attributes (eg. +files sizes, dates, ownership, and so on) H
SET : This functions allows setting of file attributes which are %not available through DCL commands. 1
UNDELETE : A safe file recovery function. =
VERIFY : This function performs a fast disk structure verification 9and can optionally repair certain disk structure errors ((comparable with ANALYZE/DISK/REPAIR).
DEach function is described in detail in the corresponding chapter.
HDFU is supported on OpenVMS VAX V5.5-2 through V7.1, and OpenVMS Alpha V6.1 thru EV7.1. DFU has been tested on the Field test versions of VMS 7.1; so Gfar no problems have been found. The official freeware release of DFU will 7be distributed with the official release of VMS V7.1. =
1.3 New features of V2.4

?This version of DFU offers several improved and new features, "as well as a couple of bugfixes. %The new functions and features are:
- Improved handling of UIC's and Identifiers. DFU now accepts all Cvalid numeric and alphanumeric UIC's and identifiers. This option Fis used in the /OWNER and /IDENTIFIER qualifier. The SEARCH, SET and UNDELETE commands use these qualifiers. E
- In some cases the DFU_ALLPRIV identifier was too restrictive; $therefore it has been removed from 9the DIRECTORY/COMPRESS, DELETE/DIR and the SET command. ;
- Output formatting is now possible on the SEARCH and DIRECTORY/VERSION Hcommands via the /FORMAT qualifier. This allows the building of action DDCL command procedures directly from the output of these commands. F
- Output file handling : the new /APPEND qualifier allows DFU to add Boutput to an existing output file instead of creating a new one. I
- DELETE/DIRECTORY : the new /KEEP qualifier allows preservation of the 8directory tree; only the directory content is deleted. B
- SEARCH : added the /OVER_ALLOCATED qualifier to search for over allocated files. F
- REPORT : Several new qualifiers allow control over the output. The /USAGE Bqualifier can now also be used as /USAGE=<uic> to report a specific uic or identifier. =
- UNDELETE: ability to undelete files marked for delete A
- VERIFY : several enhancements. VERIFY /DIRECTORY allows a complete Adirectory check; this results in better detection of lost files Aand some cases of directory problems. Note that /DIRECTORY_SCAN &replaces the DIRECTORY/CHECK comand. DAlso incorrect backlinks of the Master File Directory (000000.DIR) can now be repaired. EFinally the output of multiple allocated blocks has been improved ( is now sorted by LBN's).
%The following bugs have been fixed:
- On VAX/VMS V5.5-2 without the patch on SMGSHR installed, DFU could >exit with an ACCVIO error. A workaround has been build in to avoid this problem. A
- When processing a corrupt directory DFU could end with an 6ACCVIO error. This has been fixed by better checking of the directory file. )
- SET/MAXREC did not work properly. I
- If, during an UNDELETE command CTRL/Y was entered an extra RETURN Chad to be given to abort the UNDELETE command. This is now fixed. H
- VERIFY/FIX and UNDELETE did not always reenter the file with its Goriginal version number. DFU will now enter the file with the correct Cversion number, or the next higher version if the current version already exists. I
- Issue a correct error message when trying to use DFU on non ODS-2 "disks such as a Spiralog volume. F
- In a batch job DFU could produce unwanted blank pages when the logical DFU$NOSMG was defined.
C
1.4 Restrictions and Parameters

*The DFU program has a few restrictions :
- DFU can not handle volume sets with more than 32 members. H
- Due to changes in VMS run time libraries for DEC C DFU.EXE files Hlinked on VMS 6.2 cannot be run on VMS 6.1 and lower without relinking Dthe image. The best solution is to reinstall DFU on those systems. ;
- The SMG interface may not work at all on VMS 5.5-2. =In that case you need to install CSCPAT_0320 and re-install IDFU. Warning: CSCPAT_0320 replaces SMGSHR.EXE and may have side effects +on other applications using SMG routines.
EThe following minimum process quotas are recommended for DFU usage:
- WSQUOTA : 1500
- WSEXTENT : 3000
- DIOLM : 40
- ASTLM : 40
- FILLM : 40
- BYTLM : 30000
- PGFLQUOTA : 30000
FIf you use DFU on volume sets with a large number of members you may 3need to increase the SYSGEN parameter CHANNELCNT.
FIf you use the directory command on very large directory files (> 1000 Dblocks) and run into errors you may need to increase the following parameters:
- WSQUOTA at least 1000 + size-of-largest directory file *
- WSEXTENT : WSQUOTA + at least 1000 2
- CTLPAGES (SYSGEN parameter) : at least 100 4
- WSMAX (SYSGEN parameter) : at least WSEXTENT
FDo not change parameters unless you run into errors such as EXCEEDED QUOTA %or INSUFFICIENT WORKING SET LIMITS.
8
Chapter 2
Using DFU

EThis chapter describes the installation procedure and other actions !which must be taken to run DFU. >
2.1 Installation procedure

=DFU can be installed with the VMSINSTAL utility. During the installation VMSINSTAL does the following:
- Moves the documentation to SYS$HELP (Optional)
- Relinks DFU @
- Creates the DFU_ALLPRIV identifier needed to perform the &special functions. (See chapter 2.2)
1The DFU utility in fact contains just 2 files :
1. DFU.EXE : the DFU program *
2. DFUHLP.HLB : the on-line help file
CDFU.EXE will be moved to SYS$SYSTEM, and DFUHLP.HLB will be moved to SYS$HELP.
BYou can optionally get documentation of DFU during installation. =To install DFU log in into a privileged account and enter :
```
 $ @sys$update:vmsinstal    8  VAX/VMS Software Product Installation Procedure V6.2      It is 01-Aug-1996 at 13:46.    3  Enter a question mark (?) at any time for help.    B  * Are you satisfied with the backup of your system disk [YES]?    
```
DVMSINSTAL now asks for the distribution media and product. You can Galso specify the directory where you have the DFU_FREEWARE_024.A file instead of a device name:
```
 =  * Where will the distribution volumes be mounted: [DDCU:]    N  Enter the products to be processed from the first distribution volume set.        * Products: DFU_FREEWARE_024  8  * Enter installation options you wish to use (none):    -  The following products will be processed:             DFU_FREEWARE_ 2.4    :  Beginning installation of DFU_FREEWARE_ V2.4  at 13:46    :  %VMSINSTAL-I-RESTORE, Restoring product save set A ...      Installing DFU version 2.4    
```
C The next question will prompt you for the documentation files. H The DFU documentation is available in Line printer, PostScript, HTML and @ Bookreader format. The documentation files will be copied to SYS$HELP.
```
 @  * Do you want the documentation in Lineprinter format ? [Y]?  8  %VMSINSTAL-I-DOCMOVED, DFU024.LINE moved to SYS$HELP    E  * Do you want the documentation in PostScript(TM) format ?   [N]?  ?  * Do you want the documentation in Bookreader format ? [N]?  9  * Do you want the documentation in HTML format ? [N]?    
```
BVMSINSTAL now links the DFU image and adds the identifier to the Rightslist 6(see chapter 2.2 for the meaning of the identifier).
```
   Linking DFU image ...  *  %DFU-I-LINK, Linking DFU 2.4  image...     %DFU-S-DONE, DFU.EXE created    
```
ENext VMSINSTAL will create the DFU_ALLPRIV identifier if necessary.
```
   D  %VMSINSTAL-I-ACCOUNT, This installation adds an identifier named      DFU_ALLPRIV.  G  %UAF-I-RDBADDMSG, identifier DFU_ALLPRIV value: %X80010008 added to      rights data base      <  %VMSINSTAL-I-MOVEFILES, Files will now be moved to their     target directories...    0  Installation of DFU V2.4  completed at 13:47    
```
>You must grant any DFU user including yourself the necessary DDFU_ALLPRIV identifier if a user be allowed to use the special DFU functions. 5See chapter 2.2 for the meaning of this identifier. ;
2.2 Security and access

EDFU has some functions which must not be made available for general 2usage. Therefore DFU has 2 groups of functions :
1. Normal functions
  1. DELETE/DIRECTORY
  2. DIRECTORY
  3. REPORT
  4. SEARCH
  5. SET
  6. SPAWN 7
  7. VERIFY (except VERIFY/FIX and VERIFY/REBUILD)
  !
2. Special functions
  1. DEFRAG
  2. DELETE/FILE
  3. UNDELETE '
  4. VERIFY/FIX and VERIFY/REBUILD
7The normal functions need SYSPRV or BYPASS privilege. ?The special functions require BYPASS privilege as well as the DFU_ALLPRIV identifier granted. ?The DFU_ALLPRIV identifier is created during the installation Eprocedure. To enable a user to perform special functions the system 1manager must grant this identifier as follows :
```
 $ mc authorize  'UAF> grant/id DFU_ALLPRIV username  
```
>It is highly recommended that special functions are NOT made available to the world.
3
2.3 Running DFU

To run DFU you can enter :
```
 $ RUN disk:[mydir]DFU  
```
&or (if DFU is installed systemwide):
```
 
$ MC DFU  
```
:You can also define and use a symbol for DFU as follows:
```
 $ DFU == "$DFU"  $ DFU  
```
DFU now prompts with :
```
 2    Disk and File Utilities for OpenVMS DFU V2.4      Freeware version  6    Copyright (C) 1996 Digital Equipment Corporation    	DFU>  
```
7You can now enter DFU commands. HELP gives you online 5help. After each command DFU returns to the DFU> 8prompt. You can recall and edit commands, just as with 8DCL (20 commands will be stored in the recall buffer). "Use EXIT or CTRL/Z to leave DFU. 9If you use a symbol for DFU , you also process a single (command and return to DCL immediately:
```
 $DFU SEARCH disk/qualifiers  
```
9During a DFU run , you can interrupt DFU with CTRL/C or &CTRL/Y. These interrupts are catched 2by DFU to allow a correct rundown of the current *command. It may therefore take some time 1before DFU responds to a CTRL/C or Y interrupt. C
2.4 Using an indirect file list

>There are 3 commands, DIRECTORY, DEFRAG and SET which accept Dan indirect file as input parameter. This is achieved by using the I@ sign. An indirect file is a file containing a list of valid filenames I(each line in such a file must contain exactly one file). Such indirect =files can be the output file of the DFU Search command eg.:
```
 $ DFU  1DFU> SEARCH mydisk/CHAR=DIRECTORY/OUTPUT=x.x  !DFU> DIRECTORY/COMPRESS @x.x  
```
G
Chapter 3
The SMG output interface

IAs of version V2.2 DFU uses SMG (Screen management routines) to perform ?output for an interactive DFU session. This chapter describes Ethe layout of the DFU screen, the special commands used only in the BSMG interface and other items with respect to the SMG interface. >
3.1 Enabling/Disabling SMG

DDFU automatically selects SMG output if you run an interactive DFU :session on a terminal or workstation which supports SMG. HIn a batch job or a non-DEC terminal DFU will use normal line oriented @output. You can explicitly disable SMG by defining the logical DFU$NOSMG to any value. U
3.2 Automatic switching between SMG and Line mode
EYou may prefer to perform interactive DFU sessions in SMG mode, and Dsingle DFU commands in normal line mode. This can be done by using %the command procedure listed below:
```
   1$! Procedure to switch beteen SMG and line mode  $ DFU = "$DFU"  $ if p1 .eqs. ""  $ then  $!Interactive seesion  "$ def/user sys$input sys$command  $ dfu  $ else  !$!Single command so disable SMG  $ def/user dfu$nosmg x  /$ dfu 'p1' 'p2' 'p3' 'p4' 'p5' 'p6' 'p7' 'p8'  	$ endif  $ exit  
```
@
3.3 Layout of the SMG screen

2After starting DFU the screen looks as follows :
```
 U+-----------------------< DFU V2.4 (Freeware ) >----------------------------+  O|                                                                           |  O|     Disk and File Utilities for OpenVMS DFU V2.4                          |  O|     Freeware version                                                      |  O|     Copyright � 1996 Digital Equipment Corporation                        |  O|                                                                           |  O|     DFU functions are :                                                   |  O|                                                                           |  O|     DEFRAGMENT : Defragment files                                         |  O|     DELETE     : Delete files by File-ID; delete directory (trees)        |  O|     DIRECTORY  : Manipulate directories                                   |  O|     REPORT     : Generate a complete disk report                          |  O|     SEARCH     : Fast file search                                         |  O|     SET        : Modify file attributes                                   |  O|     UNDELETE   : Recover deleted files                                    |  O|     VERIFY     : Check and repair disk structure                          |  O|                                                                           |  O|                                                                           |  O+----------------------------------Statistics-------------------------------+  O|                                                                           |  O|                                                                           |  O+---------------------------------------------------------------------------+  O DFU>                                                                       
```
)This screen is divided into 3 sections:
- Main Screen : the top part of the screen is used for the output from @DFU commands. Also broadcast messages are send to this window. H
- Statistics : the lower part contains statistics from the current Acommand. During most of the commands this screen will contain a :progress indicator and a status for the current command. G
- DFU prompt : the bottom line is used as the input command line.
?
3.4 Special Screen commands

<In SMG mode the following keys perform special functions :
- DO : invokes a subprocess (same as the SPAWN command) H
- HELP or PF2 : invokes a special SMG window for the help command. #
- CTRL/W : redraws the screen @
- PF4 : creates a screen dump into the file DFU_SCREEN.TXT 5
- PREV SCREEN : Scrolls back the output screen. 7
- NEXT SCREEN : Scrolls forward the output screen 4
- SELECT : Toggles between 80 and 132 columns.
EAlthough only some 20 lines are visible in the output (main) screen ADFU in fact remembers 500 output lines. You can scroll back and Aforward through these lines with the NEXT and PREV SCREEN keys. CAt the beginning of each new DFU command these lines are cleared.
HOn a workstation with DecWindows/Motif you can change the DecTerm size >to be more than the standard 24 lines. DFU's SMG screen will automatically .adjust to the screen size of such a DecTerm. 4
3.5 Side effects

EThere are a few side effects when using SMG mode. CTRL/C and CTRL/Y Eare catched but not echoed. Also all broadcast messages are trapped Dand will be displayed in the main screen at the end of the current IDFU command. Sometimes this may slightly disrupt the main screen, which &can be repaired with the CTRL/W key.
@Further, during the execution of a DFU command the cursor will disappear. DAfter the command finishes the cursor will reappear at the DFU> prompt.
9
Chapter 4
DFU basics

BNote : this chapter is meant for first time users of DFU. If you already 5used DFU before you may probably skip this chapter.
GThis chapter gives a brief overview of the commands which can be used @with DFU, and how they can provide the system manager with the necessary information.
DOne of most common actions by a system manager is trying to locate specific Ffiles eg. files with a certain file size. Although a lot can be done with Bthe VMS DIRECTORY command this can be a time consuming process , especially if Ithe complete disk much be scanned. The SEARCH command of DFU is exactly meant Hfor this situation. It gives a very quick list of specific files, with Ftheir size, and if needed the number of file fragments. Some usefull SEARCH commands are :
```
 @DFU> SEARCH disk/SIZE=MINIMUM=1000 (files > 1000 blocks)  :DFU> SEARCH disk/IDENT=SYSTEM (files owned by SYSTEM)  LDFU> SEARCH disk/FRAGMENT=MINIMUM=10 (files with at least 10 fragments)  ?DFU> SEARCH disk/CHAR=MARKED (all files marked for delete)  QDFU> SEARCH disk/CREATED=SINCE=YESTERDAY (all files created since YESTERDAY)  
```
BOf course these qualifiers can be combined to narrow the search. FAs the SEARCH command scans INDEXF.SYS , not directories, the output Hgenerated by SEARCH may look a bit random (but it is just the order in Cwhich the file headers are in the INDEXF.SYS file). To smooth the output use the /SORT qualifier.
IAnother important action for a system manager is to gather some overall Hdisk information , such as number of files , free space statistics and Dfragmentation information. The REPORT command will generate such a Hdisk report. To get individual disk space usage information the /USAGE Fqualifier can be used. This will work even if there is no disk quota enabled on the disk.
EAt regular intervals a system manager may need to check a disk with EANALYZE/DISK. The DFU VERIFY command provides more or less the same Bfunctionality but many times faster. The /FIX qualifier provides Hsome REPAIR options which (unlike ANALYZE/DISK/REPAIR) do NOT lock the =disk, and thus do not interfere with other disk operations. CHowever, the disk can be rebuild completely by using the /REBUILD qualifier.
COccasionaly a user will delete the wrong file, leaving the system manager Gor operator with the tedious task of restoring the file from a backup set. HThe UNDELETE command may be able to recover the file if it has not yet Hbeen overwritten with a new one. Much care has been taken to make this Hcommand as safe as possible; therefore no disk corruptions will be the Hresult of an UNDELETE. If DFU encounters a problem with a deleted file it will refuse to UNDELETE it.
IAnother type of typical system manager problems deals with directories. CThe DFU command DIRECTORY can handle such problems. DIRECTORY can generate Ireports about empty directories (/EMPTY qualifier) or directories which >contains files with a certain number of versions (/VERSION=n qualifier). DAlso , directories may become internally fragmented which degrades Bperformance. This can be quickly solved by using DFU's directory (compressing (the /COMPRESS qualifier).
HA second problem with directories is in deleting a directory with many files. IOn large directories this may take several hours using a DCL DELETE *.* !command. This problem is solved @by using DFU's DELETE/DIRECTORY command which can delete large directories Gsome 10 times faster than the normal DELETE command does. Also, using EDELETE/DIR/TREE will delete a complete directory tree with just one command.
HThe last 2 commands deal with individual files. SET allows settings of Isome special file attributes. Since VMS V6.0 this functionality is also Fprovided by the DCL SET FILE/ATTRIBUTE command, but DFU's SET offers Gsome more options. The DEFRAG command is an interface to the MOVEFILE >function offered by VMS 5.5 and higher. This allows a simple defragmentation of individual files.
GThe next chapters gives a detailed description of each individual DFU command.

5
Chapter 5
DEFRAG

GThis chapter describes the DEFRAG command with the related parameters and qualifiers. 3
5.1 Description

GThe DEFRAG command can be used to defragment a single file or a group of Ifiles. You can also enter an indirect command file containing a list of Efiles. This feature allows you to create an output file with SEARCH %and use that as an input to DEFRAG.
EDEFRAG makes use of the file-primitive MOVEFILE function. Therefore >files which are open, or which are marked NOMOVE will not be DEFRAGmented. FStill you should be cautious about using DEFRAG. You should not make ,this function available for general usage.
6
5.2 Error messages

1The most common errors returned by DEFRAG are :
- ACCONFLICT: File is open by another user ;
- DEVICEFULL: Device has not enough contiguous free space to move the entire file 1
- FILNOTACC: File has been set to NOMOVE. G
- FILENUMCHK: You tried to move a reserved file (eg INDEXF.SYS). ;
- RMS Errors: Almost always caused by an invalid or wrong file specifcation.
(
DEFRAG

3Defragment a file or a list of files on the disk.

Format

&
DEFRAG file1,file2,@file...

PARAMETERS

file1,file2,@file...
FThe file(s) to be defragmented. You can also use an indirect command Ffile (@file) which contains a list of files to be defragmented. This may be :an output file generated with the SEARCH/OUTPUT command.

QUALIFIERS
/BESTTRY
DNormally DEFRAG tries to create a contiguous file. If there is not enough Bcontiguous free space the operation will fail. With the /BESTTRY qualifier DDEFRAG tries to move the file with the contiguous-best-try method. IThis means a maximum of 3 fragments. You should only use this qualifier Gwhen a normal DEFRAG fails. If a DEFRAG/BESTTRY also fails this is an Findication that the disks free space is too fragmented. Run a REPORT command Fto see what the largest contiguous free space is, and check the free space fragmentation index.
/DEVICE
GThe device on which the files reside. The device name is added to the Dfile name. If you generate a file list with the DFU SEARCH command Dyou don't need this qualifier anymore. However you may have a list Hof files produced from another source and thus need to append a device name to it. Example:
```
 6  DFU> SEARCH mydisk/...../frag=min=50/output=x.x    DFU> DEFRAG @x.x  
```
#
/LBN=logical-block-number
IForces a single file to be moved to the specified logical block number. <Do not use this qualifier when processing a list of files.
/STATISTICS
GThis qualifier displays the performance statistics: CPU time, Elapsed Time, I/O and PageFaults.
/WRITECHECK
<Perform a writecheck on the resultant file. The default is /NOWRITECHECK. CNote that a writecheck doubles the number of involved disk I/O's.
5
Chapter 6
DELETE

GThis chapter describes the DELETE command with the related parameters and qualifiers. 4
6.1 Introduction

0The DELETE command is designed for 2 purposes:
1. Delete a file by file id (with the /FILE qualifier). This functionality Dis needed to be able to delete files which no longer have a parent directory. FThis way 'lost' files and (sometimes) files marked for delete can be removed from a disk. H
2. A fast method to delete a complete directory or even a directory tree C(with the /DIRECTORY and /TREE qualifier). First all entries of a directory are Ddeleted without removing the directory entry ; this saves a lot of unnecessary directory updates. DFinally the directory file itself is deleted, unless the new /KEEP qualifier is used. DThis way a directory is cleaned up many times faster than with the IDCL DELETE *.* command. On large directories DFU may be even 10 or more times faster than DCL. >To delete a complete directory tree use the /TREE qualifier. =The DCL command DELETE [.SUBDIR...]*.*;* will almost always Ifail to delete the intermediate subdirectory files forcing you to issue Gthis command several times. The DFU DELETE command is smart enough to delete Ethe files and the subdirectory files in the proper order; therefore only @one command is sufficient to delete a complete directory tree. F
  The new /KEEP qualifier allows you to preserve the directory tree. DThe contents are deleted but the directory file(s) remains intact.
(
DELETE

Deletes files or directories.

Format

0
DELETE device[:] or directory-file(s)

PARAMETERS

device
8The device on which to perform the DELETE/FILE=file-id command.
directory-file(s)
<The filespecification of the directory on which to perform Ithe DELETE/DIRECTORY command. Wildcard file specifications may be used. HDFU will automatically add .DIR to the filespecification if a filetype is not provided.

QUALIFIERS

/DIRECTORY
ISpecify the directory file which must be deleted. Wildcards may be used Hbut must be used very carefully. Make sure that the directory does not Icontain non-empty subdirectories. Files within such a subdirectory will Fbecome lost after the DELETE/DIRECTORY command (but can be recovered *with ANALYZE/DISK/REPAIR). Note that the 6directory file itself will also be deleted. Example:
0
Next page... | ,Contents

DFU V2.4

Abstract

Copyright©August 1996

Contents

Chapter 1Introduction

Chapter 2Using DFU

Chapter 3The SMG output interface

Chapter 4DFU basics

Chapter 5DEFRAG

DEFRAG

Format

DEFRAG file1,file2,@file...

PARAMETERS

file1,file2,@file...

QUALIFIERS

/BESTTRY

/DEVICE

/LBN=logical-block-number

/STATISTICS

/WRITECHECK

Chapter 6DELETE

DELETE

Format

DELETE device[:] or directory-file(s)

PARAMETERS

device

directory-file(s)

QUALIFIERS

/DIRECTORY

Chapter 1
Introduction

Chapter 2
Using DFU

Chapter 3
The SMG output interface

Chapter 4
DFU basics

Chapter 5
DEFRAG

Chapter 6
DELETE