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OpenVMS Frequently Asked Questions (FAQ), Part 5/11

( Part1 - Part2 - Part3 - Part4 - Part5 - Part6 - Part7 - Part8 - Part9 - Part10 - Part11 )
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Archive-name: dec-faq/vms/part5
Posting-Frequency: quarterly
Last-modified: 02 Sep 2005
Version: VMSFAQ_20050902-05.TXT

See reader questions & answers on this topic! - Help others by sharing your knowledge
                   System Management Information

          Table 5-1 (Cont.)  PCSI Generation Number


                   0050160000        V7.2-2

                   005017xxxx        V7.2-2 ECOs

                   0060000000        V7.3

                   006001xxxx        V7.3 ECOs

                   0060020000        V7.3-1

                   006003xxxx        V7.3-1 ECOs

                   0060100000        V7.3-2

                   006011xxxx        V7.3-2 ECOs

                   0070040000        V8.2

                   007005xxxx        V8.2 ECOs

                   0070060000        V8.2-1


          5.29  How can I tell what software (and version) is installed?

                   There is unfortunately no consistent nor single way to
                   make this determination-this is one of the reasons that
                   a move to PCSI installations is underway.

                   On OpenVMS Alpha, you can use VMSINSTAL.HISTORY and
                   PRODUCT SHOW PRODUCT to determine what packages have
                   been installed via the VMSINSTAL and PCSI tools,

                   To see which OpenVMS Alpha ECO kits have been applied,
                   look in VMSINSTAL.HISTORY on OpenVMS Alpha prior to
                   V7.1-2, and use PRODUCT SHOW PRODUCT/FULL on OpenVMS
                   Alpha V7.1-2 and later.

                   On OpenVMS VAX, you can use PRODUCT SHOW PRODUCT and
                   (for software that is installed via VMSINSTAL on V7.3
                   and later) in VMSINSTAL.HISTORY.


                   System Management Information

                   For products installed on OpenVMS VAX prior to V7.3
                   using VMSINSTAL, there is no reliable way to determine
                   what products have been installed. If the product
                   provides a RELEASE_NOTES file (as many do), you
                   can look for the list of these files via DIRECTORY
                   SYS$HELP:*.RELEASE_NOTES. Again, this approach is NOT
                   reliable: some kits do not provide release notes, some
                   system managers will install only the release notes,
                   some system managers will delete release notes, and
                   release notes for multiple versions can be present.

                   On most packages, you can generally use ANALYZE/IMAGE
                   on one of the core images, looking at the image
                   identification area. Some of the product-specific
                   mechanisms available are:

                   o  DQS DQS$VERSION logical name

                   o  C CC/VERSION

                   o  C++ CXX/VERSION

                   o  TCP/IP TCPIP SHOW VERSION command

          5.30  What file checksum tools are available for OpenVMS?

                   The undocumented (prior to V8.2) DCL command CHECKSUM
                   is the usual means, and provides a rather simple-minded
                   checksum suitable to detect basic file corruptions.
                   Starting with V8.2, additional algorithms beyond the
                   classic XOR scheme are available.

                   One of the most common schemes beyond the CHECKSUM
                   XOR scheme is MD5, and information and a source code
                   example are available via the MD5 RFC. As of this
                   writing, pre-built versions of MD5 are expected to be
                   made available at or via the OpenVMS Freeware website
                   ( ), and MD5 is
                   expected to be made available on an OpenVMS Freeware
                   release after V7.0. Also see the CHECKSUM/ALGORITHM=MD5
                   command on OpenVMS V8.2 and later.


                   System Management Information

                   The OpenVMS Alpha ECO (patch) kit checksums available
                   at the ECO website are determined using the following
                   DCL command sequence:

                   $ CHECKSUM kitname.pcsi-dcx_axpexe

                   See Section 5.17 for information on acquiring OpenVMS
                   ECO (patch) kits.

          5.31  What (and where) is the OpenVMS Management Station?

                   For information and current kits for the OpenVMS
                   Management Station (OMS), a PC-based tool that permits
                   you to manage an OpenVMS system, please see:


          5.32  How to determine current disk fragmentation level?

                   The HP OpenVMS Disk File Optimizer (DFO)
                   defragmentation package provides a fragmentation
                   monitoring tool, and a DFO product authorization key
                   (PAK) is not required for the fragmentation reporting

                   $ DEFRAG SHOW/VOLUME ddcu:

                   The DFU tool available on the OpenVMS Freeware can
                   generate a report on the disk fragmentation:

                   DFU> REPORT ddcu:

          5.33  SYSBOOT-I-FILENOTLOC, Unable to locate SYS$CPU_ROUTINES?

                   A message at the OpenVMS Alpha bootstrap such as the

                   %SYSBOOT-I-FILENOTLOC, Unable to locate
                   %SYSBOOT-E-LDFAIL, failed to load execlet,
                     status = 00000910


                   System Management Information

                   indicates that the particular OpenVMS Alpha release
                   does not contain support for the target platform. In
                   this case, OpenVMS does not recognize Alpha family 1C
                   member 02 as a supported platform. A later version of
                   OpenVMS might support the platform, or there might be
                   no support on any release. Ensure that you have the
                   most current firmware, and review the minimum version
                   requirements for the platform.

                   The execlet load failure and other similar bootstrap
                   status values can often be decoded using either of the
                   following techniques:

                   $ exit %x910
                   %SYSTEM-W-NOSUCHFILE, no such file

                   $ x = f$message(%x910)
                   $ show symbol x
                     X = "%SYSTEM-W-NOSUCHFILE, no such file"

                   Also see Section

          5.34  How can I customize the DCPS device control for a new

                   To customize DCPS for an otherwise unsupported printer,
                   you can try the following sequence:

                   o  Extract the most closely-associated setup modules
                      from the existing device control library,
                      DCPS$DEVCTL.TLB. (For instance, you can probably
                      extract and use the HP LaserJet 4000 series
                      definitions for the HP LaserJet 4050 series. Each
                      printer will vary, please consult the printer
                      documentation for specifics and requirements.)

                   o  rename each extracted setup module to a



                   System Management Information

                   o  Insert all of the above-renamed setup modules into a
                      newly-created device control library specific to the
                      new printer:

                      $ LIBRARY/TEXT/CREATE -

                      The above assumes the filename HP4050_DEVCTL.TLB,
                      alter as required.

                   o  Set up your DCPS startup procedures to include a
                      search-list logical name such as:

                      $ DEFINE/SYSTEM/EXECUTIVE DCPS_HP4050_LIB  -
                          SYS$LIBRARY:HP4050_DEVCTL.TLB, -

                   o  Supply DCPS_HP4050_LIB as the library parameter
                      in the queue startup for this printer, this
                      is the P3 parameter to the command procedure

                   o  The HP4050_DEVCTL library may/will need to be
                      recreated and modules re-edited and replaced with
                      each DCPS upgrade, particularly if any modules
                      are updated in the original library. You will also
                      want to determine if the upgraded version of DCPS
                      directly supports the particular printer.

                   o  To customize the processing of file extensions
                      within DCPS (to enable or disable graybar output,
                      for instance), use the information available in:


                   to create your own site-specific:


                   Also see Section 5.15.

          5.35  Why do $GETDEV MOUNTCNT and SHOW DEVICE mount counts

                   MOUNTCNT returns the local mount count, while SHOW
                   DEVICE returns the cluster-wide mount count.


                   System Management Information

          5.36  What software is needed for Postscript printers?

                   The NorthLake PrintKit ( and DECprint
                   Supervisor (DCPS) are common choices for support of
                   Postscript printers on OpenVMS.



                   You may also require the installation of an IP
                   transport stack.

                   Also please see Section 15.2.2 and Section 15.2.3.

          5.37  How do I remove a PCSI-installed patch (ECO) kit?

                   You cannot PRODUCT REMOVE a PCSI patch (ECO) kit.

                   In order to remove an ECO kit, PCSI would have to have
                   copies of all the other version of the files from
                   all other patches and products that previously were
                   installed. This can clearly involve a large number of
                   files and a large archive of old file versions and a
                   substantial quantity of disk space. While removal is
                   clearly theoretically possible, it is not currently

                   The following is the supported mechanism to remove a
                   PCSI patch kit.

                   1  Execute a PRODUCT SHOW PRODUCT product-name. /FULL
                      command. The "maintenance" column (132 column width)
                      shows the patches that have been installed. Keep a
                      copy of this listing.

                   2  Acquire kits for all of the maintenance kits listed.

                   3  Re-install the prior FULL version of the product.
                      This will remove all patch kits, setting to product
                      back to "original" condition.

                   4  Re-install all the patches in the list from step 1,
                      except those patches which you have determined you
                      do not want.


                   System Management Information

                   The above information also applies to PCSI PARTIAL

          5.38  SYSINIT-E, error mounting system device, status=0072832C

                   This message can arise during an OpenVMS system

                   %MOUNT-F-DIFVOLMNT, different volume already mounted on this device

                   For details and further information, use the DCL

                   $ HELP/MESSAGE /STATUS=%X72832C

          5.39  Resolving License PAK Problems?

                   The PAK release date, the PAK termination date, and
                   the PAK version are the usual culprits when a license
                   product authorization key (PAK) check failure occurs.

                   The PAK termination date is the date when the license
                   PAK will expire.

                   The PAK release date is the date of the most recent
                   release date of the software package that will be
                   permitted by the particular license PAK. (The release
                   date check is analogous to a product version check.)
                   The PAK version indicates the most recent product
                   version that is permitted by the license.

                   Having multiple license PAKs registered (and active)
                   can also cause problems if an expired PAK gets loaded.
                   You will want to DISABLE license PAKs you do not wish
                   to have loaded.

                   Other problems include a failure to register each PAK
                   in all license databases throughout a multiple-system-
                   disk cluster, with a consistent set of /INCLUDE lists
                   specified across each of the duplicated PAKs.

                   Additionally, you could have an invalid LMF$LICENSE
                   logical name defined. (If no LMF$LICENSE logical
                   name is defined, the standard license database named
                   SYS$SYSTEM:LMF$LICENSE.LDB will be used.)


                   System Management Information

                   You can display license failures by defining the
                   following logical name:


                   Enable your terminal as a license operator
                   (REPLY/ENABLE=LICENSE), define the LMF$DISPLAY_
                   OPCOM_MESSAGE logical name, and then try the failing
                   operation again. You should see one or more OPCOM
                   messages displayed.

                   If you have the LMF$DISPLAY_OPCOM_MESSAGE logical name
                   defined, you can (will?) see spurious license check
                   failures-various products will check for multiple
                   licenses, and a few products will check for PAKs that
                   either have not yet been or will not be issued. Once
                   you figure out which license has failed, you will want
                   to deassign this logical name.


                      That there are no license check failures does not
                      indicate that the particular product or operation
                      or use is permissible per applicable licensing
                      agreements. Please consult the applicable
                      agreement(s) for licensing-related information
                      and requirements.

                   To register a license PAK on a DECwindows system
                   when DECwindows cannot start (because of an expired
                   license or other licensing problem), follow the steps
                   outlined in section Section 5.6 up through the use
                   of the AUTHORIZE command. In place of the AUTHORIZE
                   command, use the console to register the license PAKs.
                   Also see Section 12.4 for licensing and troubleshooting

                   For information on licensing and on the numbers of
                   license units required for various products and various
                   platforms, the License Unit Requirements Table (LURT)
                   is available at:



                   System Management Information

          5.40  Changing the OpenVMS Version Number?

                   Fool your friends, baffle your enemies, run the OpenVMS
                   version of your choice!

                   On OpenVMS Alpha systems:

                   $ SET DEFAULT SYS$COMMON:[SYS$LDR]
                   $ RUN SYSVER
                   REPLACE V9.9
                   $ EXIT

                   On OpenVMS VAX systems:

                   $ set default SYS$COMMON:[SYS$LDR]
                   $ copy SYS.EXE SYS.EXE_IN-CASE-I-FAIL
                   $ patch SYS.EXE
                   define sys$gq_version=800044b8
                   set mode ascii
                   !examine sys$gq_version
                   !examine sys$gq_version+4
                   deposit sys$gq_version   = "V9.9"
                   deposit sys$gq_version+4 = "    "
                   $ Exit

                   Then reboot the system at your leisure.

          5.41  How to prevent users from choosing obvious passwords?

                   To prevent users from selecting obvious passwords on
                   OpenVMS, you will want to use the reserved password
                   (password screening) mechanism. Effectively, you merge
                   your list of reserved passwords into the existing
                   reserved words database maintained by OpenVMS. (You can
                   also then require all users to reset their passwords-
                   via the pre-expired password mechanism-thus forcing
                   users to select new passwords.) For details on the
                   password screening mechanism, of the reserved password
                   database (VMS$PASSWORD_DICTIONARY.DATA), and details
                   of how to merge your list of prohibited passwords
                   into the database, please see the associated chapter
                   in the OpenVMS security manual. For details of the


                   System Management Information

                   password expiration mechanism, see the AUTHORIZE
                   command qualifier /PWDEXPIRED.

                   You can also implement a site-specific password filter
                   with the information provided in the back of the
                   OpenVMS Programming Concepts manual. The password
                   filter permits you to establish particular and site-
                   specific password requirements. For details, please
                   see the system parameter LOAD_PWD_POLICY and the
                   programming concepts manual, and see the examples in
                   SYS$EXAMPLES:. (Examples and documentation on V7.3
                   and later reflect both platforms, the examples are
                   found only on OpenVMS VAX kits on earlier releases.
                   The capabilities have existed on both the VAX and Alpha
                   platforms for some time now.)

                   To verify current passwords, you can also use a
                   technique known to system crackers as the "dictionary
                   attack" - the mechanism that makes this attack somewhat
                   more difficult on OpenVMS is the hashing scheme used on
                   OpenVMS, and the file protections used for the SYSUAF
                   authorization database. Given a dictionary of words and
                   the unprotected contents of the SYSUAF file, a search
                   for obvious passwords can be performed. Interestingly,
                   a "dictionary attack" also has the unfortunate side-
                   effect of exposing the password to the user-while this
                   is clearly the goal of a system cracker, authorized
                   privileged and non-privileged system users should not
                   know nor have access to the (cleartext) passwords of
                   other users.

                   Accordingly, OpenVMS does not store the cleartest
                   password. Further, OpenVMS uses a password hashing
                   algorithm, not an encryption algorithm. This means that
                   storage of a cleartext password is deliberated avoided,
                   and the cleartext value is deliberately very difficult
                   to obtain. The hash is based on a Purdy Polynomial,
                   and the hash itself includes user-specific values in
                   addition to the password, values that make the results
                   of the password hash unique to each user.

                   Regardless of the use of a password hashing scheme, if
                   a copy of your password file should become available to
                   a system cracker, you will want to force all users to
                   use new passwords immediately.


                   System Management Information

                   If you should require a user to verify a password,
                   use the username, the user's salt value (this value
                   is acquired via $getuai) and the user's specified
                   cleartext password, and compare the resulting hashed
                   value (using a call to $hash_password) against the
                   saved hashed password value (this value also acquired
                   via $getqui). For reasons of security, avoid saving
                   a cleartext password value in any data files, and do
                   not maintain the cleartext password in memory longer
                   than required. (Use of sys$acm on V7.3-1 and later is

                   Kerberos authentication (client and server) is
                   available on OpenVMS V7.3 and later. Integration of
                   Kerberos support into various Compaq and into third-
                   party products is expected.

                   External authentication is available in V7.3-1
                   and later, with support for user-written external
                   authentication in V7.3-2 and later.

                   If you are simply looking for OpenVMS access and
                   the SYSTEM and all other privileged passwords are
                   forgotten or otherwise unavailable, please see section
                   Section 5.6 and/or the OpenVMS documentation set.

                   Also please see the NCSC C2 guidelines in the OpenVMS
                   security manual.

          5.42__Please_help_me_with_the OpenVMS BACKUP utility?

          5.42.1  Why isn't BACKUP/SINCE=BACKUP working?

                   If you are seeing more files backed up than previously,
                   you are seeing the result of a change that was made to
                   ensure BACKUP can perform an incrementation restoration
                   of the files. In particular, if a directory file
                   modification date changes, all files underneath it are
                   included in the BACKUP, in order to permit incremental
                   restoration should a directory file get renamed.


                   System Management Information

  Why has OpenVMS gone through the agony of this change?

                   When a directory is renamed, the modified date is
                   changed. When the restoration needs to restore the
                   directory and its contents, and the restoration should
                   not result in the restoration of the older directory
                   name when a series of incremental BACKUPs are restored.
                   Thus an incremental BACKUP operation needs to pick up
                   all of the changes.

                   Consider performing an incremental restoration, to
                   test the procedures. This testing was how OpenVMS
                   Engineering found out about the problem that was
                   latent with the old BACKUP selection scheme-the
                   old incremental BACKUP scheme would have missed
                   restoring any files under a renamed directory. Hence
                   the change to the selection mechanisms mentioned in
                   Section 5.42.1.

  Can you get the old BACKUP behaviour back?

                   Yes, please see the /NOINCREMENTAL qualifier available
                   on recent OpenVMS versions (and ECO kits). Use of
                   this qualifier informs BACKUP that you are aware of
                   the limitations of the old BACKUP behaviour around
                   incremental disk restorations.

          5.42.2  What can I do to improve BACKUP performance?

                   Use the documented commands in the manual for
                   performing incremental BACKUPs. Use the documented
                   incremental procedures. Don't try to use incremental
                   commands in a non-incremental context.

                   Also consider understanding and then using /NOALIAS,
                   which will likely be a bigger win than will anything to
                   do with the incremental BACKUPs, particularly on system
                   disks and any other disks with directory aliases.

                   See the OpenVMS documentation for additional details.


                   System Management Information

                   Ignoring hardware performance and process quotas, the
                   performance of BACKUP during a disk saveset creation is
                   typically limited by three factors:

                   1  Default extend size

                      The default behavior can have poor performance,
                      as the extend operation can involve extensive
                      additional processing and I/O operations. Consider
                      changing the default extend value on the volume, or
                      change the extend for the process:

                      $ set rms/extend=65000

                   2  Output IO size

                      The default IO size for writing an RMS sequential
                      file is 32 blocks, an increase from the value of
                      16 blocks used on earlier versions. Setting this to
                      the maximum of 127 can reduce the number of IOs by
                      almost a factor of 4:

                      $ set rms/block=127

                      Note that the performance might be better on some
                      controllers if the block count is a multiple of 4 -
                      e.g. 124

                   3  Synchronous writes to the saveset

                      Starting with OpenVMS V7.3, you can now persuade
                      RMS to turn on write-behind for sequential files
                      opened unshared. (Please see the V7.3 release notes
                      or more recent documentation for details.) Enabling
                      the write-behind operations involves setting the
                      dynamic system parameter RMS_SEQFILE_WBH to 1.
                      This parameter is dynamic, and it can be enabled
                      and disabled without a reboot, and changes in its
                      setting can and will directly effect the running
                      system. In order to get the full benefit from write-
                      behind operations, you also need to increase the
                      RMS local buffer count from the default of 2 to a
                      larger number. Raising the value to 10 is probably a
                      reasonable first estimate for this value.


                   System Management Information

                      $ run sys$system:sysman
                      PARAMETERS USE ACTIVE
                      PARAMETERS SET RMS_SEQFILE_WBH 1
                      PARAMETERS WRITE ACTIVE
                      $ SET RMS/BUFFER=10/EXTEND=65000/BLOCK=127
                      $ BACKUP source-specification ddcu:[dir]saveset.bck/SAVE

          5.42.3  Why is BACKUP not working as expected?

                   First, please take the time to review the BACKUP
                   documentation, and particularly the BACKUP command
                   examples. Then please download and install the most
                   current BACKUP eco kit. Finally, please please set the
                   process quotas per the System Management documentation.
                   These steps tend to resolve most problems seen.

                   BACKUP has a very complex interface, and there
                   are numerous command examples and extensive user
                   documentation available. For a simpler user interface
                   for BACKUP, please see the documentation for the
                   BACKUP$MANAGER tool.

                   As for recent BACKUP changes, oddities, bugs, etc:

                   o  A change made in OpenVMS V6.2 WILL cause more files
                      to be included into a file-based BACKUP saveset
                      using /SINCE=BACKUP as all files underneath any
                      directory with a sufficiently recent (selected)
                      date will be included in the saveset. This change
                      was deliberate and intentional, and was mandated
                      by the need to provide a functional incremental

                      Without the inclusion of these apparently-extra
                      files, an incremental saveset can NOT be reliably

                   o  As part of the OpenVMS V6.2 change, the /SINCE
                      command-without the specification of the =BACKUP
                      keyword-selected more files than it should have.
                      This is a bug. This bug has been remedied in the
                      OpenVMS BACKUP source code and in some of (all of?)
                      the BACKUP ECO kits.


                   System Management Information

                   When working with BACKUP, you will want to:

                   o  Ensure you have your process quotas set per the
                      recommendations in the OpenVMS System Management
                      documentation. Deviation from these values can and
                      will lead to access violation (ACCVIO) and other
                      untoward behaviour.

                   o  Get the current BACKUP ECO kit and install it BEFORE
                      you attempt to troubleshoot any problems.

                   o  Learn about the /NOINCREMENTAL (new) and /NOALIAS
                      (V6.2 and later) command qualifiers. The former
                      qualifier returns to the pre-V6.2 behaviour of the
                      /SINCE file selection mechanism, while the latter
                      (specified with /IMAGE) reduces the replication
                      of files on system disks and other disks with file
                      alias and directory alias entries. Both of these can
                      reduce the numbers of files that will be selected
                      and thus included into the saveset.

                      Learn what /IGNORE=INTERLOCK means. This command
                      probably does not provide what you think it does-
                      those file system interlocks that this command is
                      ignoring were implemented for a reason, after all.
                      Ignoring these interlocks can lead to missed data
                      and potentially to corruptions to individual files
                      stored within the output saveset, corruptions that
                      may or may not be reported. For details on this
                      BACKUP command qualifier, please see the Ask The
                      Wizard topic (2467).

                   When working with the BACKUP callable API:

                   o  Build your applications with the most current BACKUP
                      API available. Changes made to the V7.1-2 and V7.2
                      API were incompatible with the V7.1 and V7.2-1 and
                      later APIs, and this incompatibility was repaired
                      via a BACKUP ECO kit. Do NOT build your application
                      with the versions of the BACKUP API that shipped
                      with V7.1-2 and V7.2, as these are incompatible with
                      the BACKUP API constants that were used on other


                   System Management Information

          5.42.4  How do I fix a corrupt BACKUP saveset?

                   BACKUP savesets can be corrupted by FTP file transfers
                   and by tools such as zip (particularly when the zip
                   tool has not been asked to save and restore OpenVMS
                   file attributes or when it does not support OpenVMS
                   file attributes), as well as via other means of

                   If you have problems with the BACKUP savesets after
                   unzipping them or after an FTP file transfer, you can
                   try restoring the appropriate saveset attributes using
                   the tool:


                   This tool is available on the OpenVMS Freeware (in
                   the [000TOOLS] directory). The Freeware is available
                   at various sites-see the Freeware location listings
                   elsewhere in the FAQ-and other similar tools are also
                   available from various sources.

                   In various cases, a SET FILE/ATTRIBUTES command can
                   also be used. As the parameters of this command must be
                   varied as the target BACKUP saveset attributes vary,
                   this approach is not recommended.

                   Also see the "SITE VMS", /FDL, and various other file-
                   attributes options available in various FTP tools. (Not
                   all available FTP tools support any or all of these

                   Browser downloads (via FTP) and incorrect (binary or
                   ascii FTP transfer modes) are notorious for causing
                   RMS file corruptions and particularly BACKUP saveset
                   corruptions. You can sometimes help encourage the
                   browser to select the correct FTP transfer type code
                   (via RFC1738):

                   o  ftp://host/urlname.ext;type=i ! request ftp
                      image/binary transfer

                   o  ftp://host/urlname.ext;type=a ! request ftp
                      ascii/text transfer


                   System Management Information

                   You can also often configure the particular web browser
                   to choose the appropriate transfer mode by default,
                   based on the particular file extensions, using a
                   customization menu available in most web browsers. You
                   can select that the specific file extentions involved
                   use the FTP binary transfer mode, which will reduce the
                   number of corruptions seen.

          5.42.5  How do I write a BACKUP saveset to a remote tape?

                   How to do this correctly was described at DECUS long
                   ago. On the OpenVMS host with the tape drive, create
                   the following SAVE-SET.FDL file:

                           FORMAT                  fixed
                           SIZE                    8192

                   Then create BACKUP_SERVER.COM:

                   $ !
                   $ ! BACKUP_SERVER.COM - provide remote tape service for BACKUP.
                   $ !
                   $ set noon
                   $ set rms/network=16
                   $ allocate mka500 tapedev
                   $ mount/nounload/over:id/block=8192/assist tapedev
                   $ convert/fdl=SAVE-SET sys$net tapedev:save-set.
                   $ dismount/unload tapedev
                   $ stop/id=0

                   On the node where you want to do the backup, use the
                   DCL command:

                   $ backup -
                       srcfilespec -
                       node"user pwd"::"task=backup_server"/block=8192/save

                   One area which does not function here is the volume
                   switch; multi-reel or multi-cartridge savesets. Since
                   the tape is being written through DECnet and RMS and
                   the magtape ACP, BACKUP won't see the media switch
                   and will split an XOR group across the reel boundary.
                   BACKUP might well be willing to read such a multi-
                   reel or multi-cartridge saveset (directly, not over


                   System Management Information

                   the net) as the XOR blocks are effectively ignored
                   until and unless needed for error recovery operations.
                   BACKUP likely will not be able to perform an XOR-based
                   recovery across reel or cartridge boundaries.

                   Unfortunately BACKUP can't read tapes over the network
                   because the RMS file attributes on a network task
                   access look wrong; the attributes reported include
                   variable length records.

          5.42.6  How to perform a DoD security disk erasure?

                   Sometimes refered to as disk, tape, or media
                   declassification, as formatting, as pattern erasure,
                   or occasionally by the generic reference of data
                   remanence. Various references to the US Deparment of
                   Defence (DoD) or NCSC "Rainbow Books" documentation are
                   also seen in this context.

                   While this erasure task might initially appear quite
                   easy, basic characteristics of the storage media and
                   of the device error recovery and bad block handling
                   can make this effort far more difficult than it might
                   initially appear.

                   Obviously, data security and sensitivity, the costs
                   of exposure, applicable legal or administrative
                   requirements (DoD, HIPPA or otherwise), and the
                   intrinsic value of the data involved are all central
                   factors in this discussion and in the decision of the
                   appropriate resolution, as is the value of the storage
                   hardware involved.

                   With data of greater value or with data exposure
                   (sometimes far) more costly than the residual value
                   of the disk storage involved, the physical destruction
                   of the platters may well be the most expedient,
                   economical, and appropriate approach. The unintended
                   exposure of a bad block containing customer healthcare
                   data or of credit card numbers can quite be costly,
                   of course, both in terms of the direct loss, and the
                   longer-term and indirect costs of such exposures.


                   System Management Information

                   Other potential options include the Freeware RZDISK
                   package, the OpenVMS INITIALIZE/ERASE command (and
                   potentially in conjunction with the $erapat system
                   service) and OpenVMS Ask The Wizard (ATW) topics
                   including (841), (3926), (4286), (4598), and (7320).
                   For additional information on sys$erapat, see the
                   OpenVMS Programming Concepts manual and the OpenVMS
                   VAX examples module SYS$EXAMPLES:DOD_ERAPAT.MAR. Some
                   disk controllers and even a few disks contain support
                   for data erasure. Some DSSI Disk ISEs, for instance.

                   For the prevention of casual disk data exposures,
                   a generic INITIALIZE/ERASE operation is probably
                   sufficient. This is not completely reliable,
                   particularly if the data is valuable, or if legal,
                   administrative or contractual restrictions are
                   stringent-there may well be revectored blocks that
                   are not overwritten or not completely overwritten by
                   this erasure, as discussed above, and these blocks can
                   obviously contain at least part of most any data that
                   was stored on the disk - but this basic disk overwrite
                   operation is likely sufficient to prevent the typical
                   information disclosures.

                   You will want to consult with your site security
                   officer, your corporate security or legal office, with
                   HP Services or your prefered service organization,
                   or with a firm that specializes in erasure or data
                   declassification tasks. HP Services does traditionally
                   offer a secure disk declassification service.

          5.42.7  How to enable telnet virtual terminals?

                   To enable virtual terminal support for telnet and
                   rlogin devices, add the following logical name
                   definitions into SYLOGICALS.COM:


                   See SYS$STARTUP:SYLOGICALS.TEMPLATE for details on the
                   typical contents of SYLOGICALS.COM.


                   System Management Information

                   In SYSTARTUP_VMS.COM, ensure that a command similar to
                   the following is invoked:


                   In MODPARAMS.DAT, add the following line or (if already
                   present) mask the specified hexidecimal value into an
                   existing TTY_DEFCHAR2, and perform a subsequent AUTOGEN
                   with an eventual reboot:

                   TTY_DEFCHAR2 = %X20000

                   This value is TT2$M_DISCONNECT.

                   On older TCP/IP Services-versions prior to V5.0-you
                   will have to perform the following UCX command:

                   $ UCX

  Volume Shadowing MiniCopy vs MiniMerge?

                   MiniMerge support has been available for many years
                   with OpenVMS host-based volume shadowing, so long as
                   you had MSCP controllers (eg: HSC, HSJ, or HSD) which
                   supported the Volume Shadowing Assist known as "Write
                   History Logging".

                   If you are interested in mini-merge and similar
                   technologies, please see the Fibre Channel webpage
                   and the information available there:


                   Mini-Merge support was originally intended to be
                   controller-based and was expected with HSG80 series
                   storage controllers and was expected to require ACS 8.7
                   and OpenVMS Alpha V7.3-1.

                   Host-based Mini-Merge (HBMM) is now available for
                   specific OpenVMS releases via a shadowing ECO kit,
                   and is also present in OpenVMS V8.2 and later. HBMM
                   applies to the HSG80 series and-like host-based volume
                   shadowing-to most other (all other?) supported storage


                   System Management Information

                   The following sections describe both Mini-Copy and
                   Mini-Merge, and can provide a basis for discussions.


                   A Shadowing Full Copy occurs when you add a disk to an
                   existing shadowset using a MOUNT command; the entire
                   contents of the disk are effectively copied to the
                   new member (using an algorithm that goes through in
                   127-block increments and reads one member, compares
                   with the target disk, and if the data differs, writes
                   the data to the target disk and loops back to the
                   read step, until the data is equal for that 127-
                   block section). (This is one of the reasons why the
                   traditional recommendation for adding new volumes to
                   a shadowset was to use a BACKUP/PHYSICAL copy of an
                   existing shadowset volume, simply because the reads
                   then usually matched and thus shadowing usually avoided
                   the need for the writes.)

                   If you warn OpenVMS ahead of time (at dismount time)
                   that you're planning to remove a disk from a shadowset
                   but re-add it later, OpenVMS will keep a bitmap
                   tracking what areas of the disk have been modified
                   while the disk was out of the shadowset, and when you
                   re-add it later with a MOUNT command OpenVMS only has
                   to update the areas of the returned disk that the bit-
                   map indicates are now out-of-date. OpenVMS does this
                   with a read source / write target algorithm, which is
                   much faster than the shenanigans the Full Copy does,
                   so even if all of the disk has changed, a Mini-Copy is
                   faster than a Full Copy.


                   A Shadowing Merge is initiated when an OpenVMS node
                   in the cluster (which had a shadowset mounted) crashes
                   or otherwise leaves unexpectedly, without dismounting
                   the shadowset first. In this case, OpenVMS must ensure
                   that the data is identical, since Shadowing guarantees
                   that the data on the disks in a shadowset will be
                   identical. In a regular Merge operation, Shadowing uses


                   System Management Information

                   an algorithm similar to the Full Copy algorithm (except
                   that it can choose either of the members' contents
                   as the source data, since both are considered equally
                   valid), and scans the entire disk. Also, to make things
                   worse, for any read operations in the area ahead of
                   what has been merged, Shadowing will first merge the
                   area containing the read data, then allow the read to

                   A Merge can be very time-consuming and very I/O
                   intensive. If a node crashes, the surviving nodes can
                   query to determine what exact areas of the disk the
                   departed node was writing to just before the crash,
                   and thus Shadowing only needs to merge just those few
                   areas, so this tends to take seconds, as opposed to
                   potentially requiring many minutes or even hours for a
                   regular full Merge.

          5.43  Please explain DELETE/ERASE and File Locks?

                   DELETE/ERASE holds the file lock and also holds a
                   lock on the parent directory for the duration of the
                   erasure. This locking can obviously cause an access
                   conflict on either the file or on the directory-
                   it might well pay to rename files into a temporary
                   directory location before issuing the DELETE/ERASE,
                   particularly for large files and/or for systems with
                   multiple overwrite erase patterns in use; for any
                   systems where the DELETE/ERASE erasure operation will
                   take a while.

          5.44  Managing File Versions?

                   Some applications will automatically roll file
                   version numbers over, and some will require manual
                   intervention. Some will continue to operate without the
                   ability to update the version, and some will be unable
                   to continue. Some sites will specifically (attempt to)
                   create a file with a version of ;32767 to prevent the
                   creation of additional files, too.


                   System Management Information

                   To monitor and resolve file versions, you can use
                   commands including:

                   $ SET FILE/VERSION_LIMIT=n filename
                   $ SET DIRECTORY/VERSION_LIMIT=n [directory]

                   And you can also monitor file version numbers, and
                   can report problems with ever-increasing file versions
                   to the organization(s) supporting the application(s)
                   generating files with ever-increasing version numbers
                   for details on potential problems, and for any
                   recommendations on resetting the version numbers for
                   the particular product or package. If required, of

                   The following pair of DCL commands-though obviously
                   subject to timing windows- can be used to rename
                   all the versions of a file back down to a contiguous
                   sequence of versions starting at 1:

                   $ RENAME file.typ;*   RENAME.TMP;
                   $ RENAME RENAME.TMP;* file.typ;

                   The key to the success of this RENAME sequence is the
                   specification of (only) the trailing semicolon on the
                   second parameter of each of the RENAME commands.

                   You may also see the numbers of files reduced with
                   DELETE commands, with multiple directories, or with
                   PURGE commands such as the following examples:

                   $ PURGE/BEFORE="-2-"
                   $ PURGE/BEFORE="TODAY-2-"
                   $ PURGE/KEEP=10"

                   You can use DFU (Freeware) to quickly and efficiently
                   scan for all files with large(r) version numbers:

                   DFU SEARCH/VERSION=MINIMUM=nnnn

                   If you are creating or supporting an application,
                   selecting temporary or log file filenames from among
                   a set of filenames-selecting filenames based on time,
                   on process id, on the day of week, week number, or
                   month, on the f$unique lexical (V7.3-2 and later), etc-
                   is often useful, as this approach more easily permits
                   on-line adjustments to the highest file versions and
                   easily permits on-line version compression using


                   System Management Information

                   techniques shown above. With differing filenames,
                   you are less likely to encounter errors resulting
                   from files that are currently locked. You can also
                   detect the impending version number limit within the
                   application, and can clean up older versions and roll
                   the next file version creation to ;1 or such.

                   Also see Section 9.4.

          5.45  Host-based Volume Shadowing and RAID?

                   Host-based Volume Shadowing (HBVS) is Disk Mirroring is
                   RAID Level 1.

                   HBVS is capable of shadowing devices of different
                   geometries, of different block counts (with
                   dissimilar device shadowing; allowing for mixtures
                   of hardware) and-with dynamic volume expansion-of
                   growing volumes on the fly, and HBVS is capable of
                   shadowing/mirroring/raid-1 operations across cluster
                   configurations up to the full span-please see the
                   Cluster SPD for the current supported span; the
                   supported span limit is currently multiple hundreds
                   of kilometers-of a cluster. HBVS can be layered onto
                   controller (hardware) RAID, as well.

                   For information on host-based striping, please see the
                   StorageWorks RAID product.



          6        Information on Mail

          6.1  MAIL keeps saying I have new messages, but I don't. What do
               I do?

                   if you see the %MAIL-W-NONEWMAIL, no new messages error
                   reported when MAIL indicates you have messages, then
                   the NEWMAIL count has become skewed from reality.

                   The count of new mail messages is kept separately
                   from your mail folder, and is stored in VMSMAIL_
                   PROFILE.DATA. It sometimes happens that this count
                   differs from what is stored in your mail folder. If
                   this arises, invoke MAIL and repeatedly enter the
                   READ/NEW command (or press the keypad hyphen key on
                   an LK-compatible keyboard) until you see no new mail
                   messages. Then enter the command one more time. This
                   will resynchronize the counters.

                   If you are operating in a cluster and find your mail
                   counts inconsistent across cluster members, your
                   customer is likely missing a definition of the VMSMAIL_
                   PROFILE logical name-and is probably also missing
                   definitions of other logical names associated with
                   other shared files-or has one or more inconsistent
                   definitions of this and likely of other logical names.

                   For details on the configuration data files that
                   must be shared within a cluster, please see
                   SYS$STARTUP:SYLOGICALS.TEMPLATE on V7.2 and later.

          6.2  How do I send or read attachments in VMS MAIL?

                   Is there any way to send or read mail with files as
                   attachments from VMS?


                   Information on Mail

                   Not directly with the OpenVMS MAIL facility, but there
                   are several other options:

                   o  Install PINE, available commercially from Innosoft
                      or free from Andy Harper. With PINE you can both
                      send and receive MIME messages, if you have the
                      appropriate viewers available.




                   o  If you are working from an X Windows display, you
                      can use the OpenVMS version of Netscape Navigator or
                      Mozilla. The mail download protocol chosen to access
                      the mail server from the Navigator or Mozilla mail
                      client can be POP or IMAP, with the former causing
                      messages to be downloaded while the latter permits
                      messages to be retained on the mail server. Most
                      folks prefer IMAP for this reason.

                   o  MPACK/MUNPACK. To send a MIME mail, construct the
                      message with attachments manually using MPACK. You
                      cannot send the resulting file directly through MAIL
                      because an extra blank header line will be inserted
                      between your message and the OpenVMS MAIL headers,
                      which will cause the message to appear as plain text
                      in most mail programs. Some TCP/IP stacks provide
                      a work around for this problem, and if that doesn't
                      work, you should generally be able to force the
                      message directly into the SMTP port of your mail
                      machine. Examples of both methods are in:


                      To read a MIME mail message, open it in MAIL,
                      extract it to a file, then use MUNPACK to break
                      out and decode the attachments.

                      MPACK/MUNPACK tools are also available on OpenVMS
                      Freeware V5.0.

                   o  With OpenVMS V7.2 and later, use the MIME tool
                      supplied with OpenVMS.


                   Information on Mail

          6.3  How can I block SMTP mail relay spam?

                   Use the anti-spam capabilities present in the TCP/IP
                   Services V5.1 and later SMTP servers.

                   Use a firewall.

                   On earlier TCP/IP Services releases, some simple DCL
                   can reportedly prevent relay SMTP spam. Use the UCX
                   command SHOW SERVICE SMTP/FULL to find the directory
                   containing the UCX$SMTP_RECV_STARTUP.COM file, and
                   insert the following DCL:

          $       !
          $       ! Block spam.
          $       !
          $       MY_ADDRESS_LONG[0,32]=F$INTEGER(F$TRNLNM("SYS$REM_NODE")-"::")
          $       MY_ADDRESS=F$FAO("!UB.!UB.!UB.!UB",F$CVUI(0,8,MY_ADDRESS_LONG),-
          $       MY_ADDRESS_REVERSE=F$FAO("!UB.!UB.!UB.!UB",-
          $       IF $STATUS.EQ.1
          $       THEN
          $         WRITE SYS$OUTPUT "SPAM from relay rejected"
          $         EXIT
          $       ENDIF
          $       IF $STATUS.EQ.1
          $       THEN
          $         WRITE SYS$OUTPUT "SPAM source relay rejected"
          $         EXIT
          $       ENDIF
          $       !
          $       ! Run receiver.
          $       !
          $       run sys$system:ucx$smtp_receiver.exe
          $       goto exit



          7        Information on Utilities

          7.1  How do I play an audio CD on my workstation?

                   If you've installed the DECwindows examples, you'll
                   find DECW$CDPLAYER.C, .DAT, .EXE, .UIL, and .UID.
                   Copy the .UID and .DAT files to DECW$USER_DEFAULTS:
                   (typically SYS$LOGIN:), define the logical name
                   DECW$CD_PLAYER to be the device name of your CD-ROM
                   drive (eg. DKA400:), give yourself PHY_IO and DIAGNOSE
                   privileges, and run the .EXE. (These privileges are
                   required, as the access to the CD-related extensions
                   will require the use of the privilege-protected IO$_
                   DIAGNOSE I/O function code.) You can also install
                   the image with these privileges. See the source for
                   additional details - note that the comments regarding
                   the need for SYSGEN CONNECT are no longer applicable
                   (at least as of VMS V5.5-2).

                   There's also SYS$EXAMPLES:CDROM_AUDIO.C and .EXE,
                   a non-Motif program, available on OpenVMS VAX, and
                   DECW$EXAMPLES:DECW$CDPLAYER.* on OpenVMS VAX and
                   OpenVMS Alpha.

                   The standard OpenVMS ATA (IDE) SYS$DQDRIVER device
                   driver does not support the necessary does not
                   support the necessary IO$_DIAGNOSE function code
                   that is required for access to audio CD media
                   commands (on OpenVMS versions prior to V7.3), but
                   an updated SYS$DQDRIVER device driver (source
                   code and all) with this capability and with the
                   source code of an updated DECW$CDPLAYER CD audio
                   player is available on the OpenVMS Freeware website
                   (, look for the
                   directory /dqdriver/), and these updates are also
                   included on OpenVMS Freeware V5.0, and OpenVMS ECO
                   kits containing newer versions of the driver are
                   available. Freeware V6.0 has a version of DQDRIVER
                   that is newer than that of the OpenVMS Alpha V7.3-2


                   Information on Utilities

                   release, with additional capabilities and with improved
                   error diagnostics.

                   OpenVMS Alpha V7.3 and later include a version of
                   SYS$DQDRIVER with the necessary IO$_DIAGNOSE support.

          7.2  How do I access a Microsoft Windows floppy disk from

                   The HP Advanced Server (formerly known as PATHWORKS)
                   for OpenVMS product includes an unsupported and
                   undocumented utility called PCDISK, and this tool can
                   read and write various Microsoft MS-DOS and Microsoft
                   Windows FAT-format diskettes, and can usually access
                   FAT-format volumes written by other operating systems.

                   ProGIS in Germany sells a product called VMove which
                   supports DOS files on many different device types. For
                   more information, send mail to

                   Engineering Software has a product called VAKSAT
                   which will read, write, and erase files on MS-DOS FAT
                   diskettes. Available for both VAX and Alpha. Contact
          for more information.

                   MadGoat PC Exchange (PCX) is a utility for copying
                   files to and from MS-DOS and Microsoft Windows (FAT)
                   format diskettes under OpenVMS, using an RX23 (3.5"),
                   RX26 (3.5"), or RX33 (5.25") diskette drive. For 3.5"
                   diskettes, high-density disks can be read or written;
                   double-density disks are read-only. Only high-density
                   disks are supported on the RX33.


                   The Freeware package WINFX is available on Freeware
                   V6.0, and can read the FAT volume structure.



                   Information on Utilities

          7.3  How do I play sound files on an AlphaStation? DECsound
               doesn't work.

                   Various of the more recent AlphaStation systems use
                   a different sound board (Microsoft Sound System) than
                   the earlier DEC 3000 series systems, and DECsound,
                   as supplied by DECwindows Motif, doesn't support
                   this board nor this interface. HP offers an optional
                   product, Multimedia Services (MMOV) for OpenVMS:


                      OpenVMS typically uses SPD 25.01.xx, SPD 41.87.xx,
                      and SPD 82.35.xx.

                   which provides a replacement for DECsound for this card
                   as well as many other features (an AVI and MPEG player,
                   video capture support, etc.)

                   Ensoniq sound support is also available.

          7.4  How do I read IBM EBCDIC tapes on OpenVMS?

                   Most (all?) IBM EBCDIC-based systems can read and write
                   ANSI-labeled ASCII magtapes. Fixed-length records
                   (MOUNT /FOREIGN /BLOCKSIZE=512 /RECORDSIZE=512, for
                   one-block records) and the DCL COPY command can be
                   used to transfer fixed-record-size text files out onto
                   tape media, or to read from fixed-record tape media.
                   Please consult the IBM documentation for the details
                   and command syntax needed when reading and writing ANSI
                   media using IBM JCL or other applicable IBM command

                   There exists various freeware around (TAPECOPY, ETAPE,
                   TCOPY, MTEXCH) that can read and write EBCDIC tapes.
                   Visit the Encompasserve (DECUS) website software
                   archives search engine and search for "EBCDIC" for


                   OpenVMS does not include an integrated tool for
                   EBCDIC tape processing, but does provide a character
                   conversion API useful within application programs.


                   Information on Utilities

                   One source for ETAPE is:


                   The OpenVMS Freeware V5.0 distribution included this
                   ETAPE tool, as well.

          7.5  How can I patch an OpenVMS Alpha image?

                   Using the OpenVMS Freeware tool ZAP:

                   o  Look for the RMS_TOOLS directory on Freeware V5.0:

                   tell ZAP to read a block (bucket) of information
                   based on the virtual block number (VBN), using X for
                   hexadecimal. Dump yourself into the OpenVMS debugger
                   with R2 pointing into the buffer, EXAMINE/INSTRUCTION
                   as needed, alter the buffer as required, GO to get out
                   of the debugger and back into ZAP, and use the ZAP W
                   command to write the updated block.



          8        DCL Details

          8.1  DCL Symbols and OpenVMS Logical Names?

                   DCL symbols are programming-style variables implemented
                   within the DCL command interpreter, and these are
                   used both for programming and to provide command
                   verb synonyms. Symbols are local to the command
                   interpreter operating within a particular process,
                   and are not shared. Lists of symbols can be copied into
                   subprocesses during a subprocess creation operation,
                   but these symbols are neither copied back into the
                   parent process when the subprocess exits, nor are
                   symbols ever shared across processes.

                   Symbols can be specified in and utilized in basic
                   mathematical operations, and bit-level operations are
                   available with the f$cvsi and f$cvui bit extraction
                   lexical functions, and with the square-brackets
                   notation for bit insertion (see Section 8.13 for an
                   example), and with bitwise operators. Symbols are of
                   two basic types, STRING and INTEGER, and these (or an
                   undefined symbol) can be differentiated with the f$type
                   lexical function. DCL symbols can also be used as a
                   mechanism to abbreviate a DCL command verb, or an easy
                   way to invoke a DCL command procedure.

                   Symbols can have local or global scope within a
                   process, and scope is affected by nested procedure
                   calls and DCL constructs such as CALL and SET SCOPE,
                   but such discussions are beyond the scope of this

                   OpenVMS Logical names can store device names, device
                   and directory specifications, rooted or searchlist
                   specifications, and full filenames. Logical names can
                   also store arbitrary data, but there are no native
                   mathematical or bitwise operators available. Analogous
                   to DCL symbols, process-local logical names can be
                   copied into subprocesses during a subprocess creation


                   DCL Details

                   operation, but these process-local logical names are
                   neither copied back into the parent process when the
                   subprocess exits, nor are these logical names ever

                   Logical names are implemented deep within the OpenVMS
                   executive, and are organized into logical name tables.
                   Logical names can be stored in tables private to a
                   process( LNM$PROCESS, the process-local logical name
                   table) , that can be shared among processes in the same
                   job tree ( LNM$JOB, the job logical name table) or in
                   logical name tables that are shared among larger groups
                   of processes (eg: LNM$GROUP, the UIC group logical
                   name table and LNM$SYSTEM, the system-wide logical name
                   table). Logical names are centrally intended to provide
                   various I/O-related capabilities, including device
                   independence and configuration customization-correctly-
                   written application programs can use logical names to
                   avoid embedding specific device or device and directory
                   specifications, and to allow filename and configuration

                   One of the most powerful capabilities of logical names
                   beyond the device independence provided involves the
                   defaulting capabilities; you can use RMS parsing
                   (directly, or with mechanisms such as the f$parse
                   lexical function) to provide a filename and a default
                   filename. To provide the mechanism that allows SYSUAF
                   to be located in an arbitrary position or even an
                   arbitrary filename, a construct similar to the
                   following is used:

                   $ UAF = F$PARSE("SYSUAF","SYS$SYSTEM:.DAT")

                   This design allows the logical name SYSUAF to be
                   optionally defined, and - when present-to specify the
                   particular location and name of the file. Portions
                   of the full file specification that are omitted are
                   retrieved using the default translation of SYS$SYSTEM:
                   and the file type of .DAT.

                   Logical names also have assigned processor modes, as
                   some translations must be trustworthy. In the example
                   above, only trusted and privileged system users should
                   be able to redirect the SYSUAF authorization database,


                   DCL Details

                   so any definition of the SYSUAF logical name must be
                   made in EXECUTIVE mode in a trusted logical name table.

                   As for common OpenVMS terminology, logical names are
                   "defined" and the associated processing is refered to
                   as "translation", while symbols are "equated" and the
                   associated processing is refered to as "substitution".
                   "Lexical functions" are processing routines built
                   into DCL, and typically prefixed with f$. Many of the
                   lexical functions are built upon correspondingly-named
                   system services, though not all.

                   Symbol substitution occurs only when the DCL command
                   interpreter is reading and processing the command
                   input; for information on DCL symbol substitution, see
                   Section 8.10. For program access, see the RTL routines
                   lib$set_symbol and lib$get_symbol.)

                   For information on logical name translation, please see
                   f$trnlnm lexical function and the DCL commands DEFINE
                   and DEASSIGN, as well as underlying system services
                   such as sys$trnlnm. Logical name translation occurs
                   when requested, or as the file or I/O operation is

                   Please see the OpenVMS User's Guide in the OpenVMS
                   documentation set for a far more detailed description
                   of these constructs.

                   For related materials, please see Section 8.10 and
                   Section 8.11.

          8.2  How do I run a program with arguments?

                   The RUN command does not accept arguments. To pass
                   arguments to a program, you must use what is called
                   a "foreign command", and either an explicit command
                   as shown here, or an automatic foreign command. For

                   $ unzip :== $disk:[dir]unzip.exe
                   $ unzip -?


                   DCL Details

                   The leading $ in the equivilence name for the symbol
                   definition is what makes the DCL symbol a foreign
                   command. If the device and directory are omitted,
                   SYS$SYSTEM: is assumed.

                   Under OpenVMS V6.2 and later, DCL supports automatic
                   foreign command definition via the logical name
                   DCL$PATH. An example of a definition of this logical
                   name is:

                   $ DEFINE DCL$PATH SYS$DISK:[],ddcu:[mytooldir],SYS$SYSTEM:

                   DCL will first look for a command in the DCL command
                   table, and if no match is found and if DCL$PATH is
                   defined, it will then look for command procedures and
                   executable images with filenames matching the command
                   specified, in the directories specified via DCL$PATH.
                   The first match found is invoked, and under OpenVMS,
                   the DCL$PATH support will cause a command procedure to
                   be activated in preference to an executable image.

                   For more information on foreign commands or on
                   automatic foreign command support, see the OpenVMS
                   User's Manual.

                   See also Section 10.3.

                   If you want to create a detached process that takes
                   arguments from a command line, it must be run under the
                   control of a command line interpreter (CLI) (typically
                   DCL). This is done by placing the command line in a
                   file, specifying SYS$SYSTEM:LOGINOUT.EXE as the image
                   to run and the command file as the input. For example:

                   $ OPEN/WRITE CMD TEMP_INPUT.COM
                   $ WRITE CMD "$ MYCOMMAND arguments"
                   $ CLOSE CMD

                   Various OpenVMS library calls (such as lib$spawn(),
                   cli$dcl_parse(),  and the C library system() call)
                   require access to a command line interpreter such as
                   DCL to perform requested actions, and will not operate
                   if a CLI is not available.


                   DCL Details

                   When a CLI is not available, these calls typically
                   return the error status SS$_NOCLI. And as mentioned
                   above, invoke the image LOGINOUT to cause a CLI (such
                   as DCL) to be mapped into and made available in the
                   context of the target process.

                   For examples of how TCP/IP Services sets up its foreign
                   commands (which includes tools such as uuencode
                   and uudecode), please see the DCL command procedure

                   Also see Section 8.12.

          8.3  How can I clear the screen in DCL?

                   The simplest way is the TYPE/PAGE NLA0: command.

                   You can set up a symbol to clear the screen in your

                   $ CLS :== TYPE/PAGE NLA0:

          8.4  Using REPLY/LOG from DCL? Disabling Console OPCOMs?

                   Your terminal must be enabled as an operator terminal
                   before the REPLY/LOG command can be used, but a DCL
                   procedure (batch command file, system startup, etc)
                   does not have an associated terminal. To make this
                   work, use the following sequence to enable the OPA0:
                   console as the operator terminal, then the REPLY/LOG
                   command will be accepted:

                   $ DEFINE/USER SYS$COMMAND _OPA0:
                   $ REPLY/LOG
                   $ DEFINE/USER SYS$COMMAND _OPA0:
                   $ REPLY/ENABLE

                   To disable the system console terminal (OPA0:) as an
                   operator terminal, use the following command:

                   $ DEFINE/USER SYS$COMMAND _OPA0:
                   $ REPLY/DISABLE


                   DCL Details

                   Also see SYLOGICALS.COM (and SYLOGICALS.TEMPLATE) for
                   information on configuring the behaviour of OPCOM,
                   including the (default) use of the system console
                   (OPA0:) as an operator terminial and the specific
                   contents and behaviour of the system operator log file

          8.5  How do I generate a random number in DCL?

                   With V7.3-2 and later, f$unique can be useful
                   here. Alternatively, here is a pseudo-random number
                   generator, just do a GOSUB RAND and the global symbol
                   RANDOM will contain a randomly generated number. You
                   can feed the generator a ceiling value (__CEIL)  or a
                   new seed (__SEED).

          $! RAND - returns a positive random number ("RANDOM") between 0 and
          $!        __CEIL - 1.
          $ RAND:
          $ IF F$TYPE(__SEED) .EQS. ""
          $ THEN
          $     ! seed the random number generator, ...
          $     __NOW = F$CVTIME()
          $     __HOUR = 'F$EXTRACT(11,2,__NOW)'
          $     __MINUTE = 'F$EXTRACT(14,2,__NOW)'
          $     __SECOND = 'F$EXTRACT(17,2,__NOW)'
          $     __TICK = 'F$EXTRACT(20,2,__NOW)'
          $     __SEED == __TICK + (100 * __SECOND) + (6000 * __MINUTE) + -
                   (360000 * __HOUR)
          $     ! the generator tends to do better with a large, odd seed, ...
          $     __SEED == (__SEED .OR. 1)
          $     ! clean up, ...
          $     DELETEX/SYMBOL __NOW
          $     DELETEX/SYMBOL __HOUR
          $     DELETEX/SYMBOL __MINUTE
          $     DELETEX/SYMBOL __SECOND
          $     DELETEX/SYMBOL __TICK
          $ ENDIF
          $ IF F$TYPE(__CEIL) .EQS. "" THEN __CEIL = %X3FFFFFFF


                   DCL Details

          $ __SEED == __SEED * 69069 + 1
          $ RANDOM == (__SEED.AND.%X3FFFFFFF)/(%X40000000/__CEIL)
          $ RETURN

          8.6  What does the MCR command do?

                   The MCR is an artifact of RSX compatibility mode, the
                   operating system from which OpenVMS is descended. MCR
                   is the Monitor Console Routine, and the command is
                   intended to activate RSX compatibility mode utilities.
                   When used on OpenVMS, the command is most commonly
                   used to run the specified image and-because the tool
                   detects the image is not a compatibility-mode image-
                   it acts as a form of RUN command with the default
                   file specification of SYS$SYSTEM:.EXE. MCR passes any
                   (optional) command line arguments in a fashion similar
                   to a foreign command. In other words:

                   $ MCR FOO BAR

                   is equivalent to:

                    $ FOO :== $FOO
                    $ FOO BAR

                   MCR is not documented. Use of a foreign command or the
                   DCL$PATH mechanism is preferred. For details on this,
                   see Section 8.2.

          8.7  How do I change the OpenVMS system prompt?

                   You can use the SET PROMPT command for this purpose.
                   SET PROMPT sets the DCL prompt to the specified string.

                   When you want to display variable information, you
                   will need to establish a tie-in that provides the
                   information to the SET PROMPT command as required.

                   If you wish to display the default directory for
                   instance, you will have to establish a tie between
                   the SET DEFAULT command and the SET PROMPT commands, as
                   there is no direct way to get the default directory as


                   DCL Details

                   the DCL prompt. You can easily acquire or create a set
                   of DCL command procedures that perform the SET DEFAULT
                   and SET PROMPT for you. These DCL command procedures
                   often use a command such as:

                   $ set prompt='f$environment("default")'

                   More advanced users could implement a system service or
                   other intercept, and use these tools to intercept the
                   directory change and reset the prompt accordingly.
                   (This approach likely involves some kernel-mode
                   programming, and requires write access to various
                   undocumented OpenVMS data structures.)

                   There are related tools available from various sources,
                   including the following web sites:



                   o  James F. Duff has also made available a Macro32 tool
                      known as TIME_PROMPT, a tool that sets the prompt to
                      the current system time.

                   o  Many folks have contributed DCL procedures to
                      perform this task. Visit the newsgroup archives
                      for information and examples.

          8.8  Can I do DECnet task-to-task communication with DCL?

                   Yes, you can do this with DCL.

                   The OpenVMS DECnet documentation shows various simple
                   examples using the task object and the TYPE command to
                   trigger the execution of a DCL command procedure on a
                   remote node. An example DCL command procedure that is
                   rather more advanced than using the TYPE command as a
                   trigger is included in the Ask The Wizard area:


                   For additional information on the OpenVMS Ask The
                   Wizard (ATW) area and for a pointer to the available
                   ATW archive, please see Section 3.8.


 ---------------------------- #include <rtfaq.h> -----------------------------
    For additional, please see the OpenVMS FAQ --
 --------------------------- pure personal opinion ---------------------------
        Hoff (Stephen) Hoffman   OpenVMS Engineering   hoff[at]

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Last Update March 27 2014 @ 02:11 PM