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From:
[email protected] (Hoff Hoffman)
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[email protected]
Organization: HP
Subject: OpenVMS Frequently Asked Questions (FAQ), Part 4/9
Summary: This posting contains answers to frequently asked questions about
the OpenVMS operating system from HP, and the computer systems on
which it runs.
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Date: Thu, 03 Jul 2003 17:13:08 GMT
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System Management Information
__________________________________________________________
5.24 INITIALIZE ACCVIO and ANSI tape label support?
A change was made (back in 1988) to (as it was then
known) VAX/VMS V5.1-1 that added support for the then-
new ANSI X3.27-1987 magnetic tape label standard. Prior
to the ANSI X3.27-1987 standard, the date field in the
ANSI HDR1 record permits dates only as far as the end
of Year 1999. With ANSI X3.27-1987, dates through Year
1999 and dates from Years 2000 to 2099 are permitted.
Versions of INIT.EXE and MTAACP.EXE from VAX/VMS
releases prior to V5.1-1 will potentially have problems
properly processing ANSI magnetic tapes when Y2K and
later dates are involved-the DCL INITIALIZE command is
known to encounter access violation (ACCVIO) errors.
The available solutions include upgrades, or setting
the date back. Direct initialization of the tape with
the new headers (via $qio) is also clearly possible,
though the limitation within the old MTAACP.EXE magtape
ACP image is not nearly so easy to bypass.
__________________________________________________________
5.25 How do I recover from INSVIRMEM errors?
Prior to OpenVMS Alpha V7.0 and on all OpenVMS VAX
releases, VIRTUALPAGECNT and PGFLQUOTA limit the amount
of virtual address space that is available to each
process.
Further limiting the amount of address space is the
size of system space (S0 and S1 space). On OpenVMS
Alpha versions prior to V7.0 and on all OpenVMS VAX
releases, VIRTUALPAGECNT and MAXPROCESSCNT together
determine the size of the page table data structures
that occupy large tracts of system space. When no
system virtual address space is available for the stuff
that needs it-this includes the page tables, non-paged
pool, and various other structures-then the values of
VIRTUALPAGECNT and MAXPROCESSCNT cannot be increased.
In OpenVMS Alpha V7.0 and later, the page table data
structures have been moved out of S0 and S1 space and
into page table space. In OpenVMS Alpha V7.2 and later,
certain large data structures found in non-paged pool
(eg: lock management structures) have been moved into
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64-bit space, thus freeing up room in non-paged pool
and in S0 and S1 space (where non-paged pool resides)
while also permitting much larger data structures.
__________________________________________________________
5.26 How can I prevent a serial terminal line from initiating a
login?
In SYSTARTUP_VMS.COM, issue the command:
$ SET TERMINAL/NOTYPEAHEAD/PERMANENT ddcu:
This will prevent any unsolicited terminal input on
ddcu:, and this unsolicited input is what triggers
JOB_CONTROL to start up LOGINOUT on the terminal. Once
LOGINOUT starts up on the serial line, you can see
interesting behaviour (eg: audits, process creations,
etc) as LOGINOUT tries to "chat" with whatever device
is hooked onto the remote end of the serial terminal
line.
__________________________________________________________
5.27 How does PCSI use the image BUILD_IDENT field?
The (undocumented) build ident field in an OpenVMS
Alpha image header is 16 bytes long, and is used as
a counted string of 0-15 characters (ie, as an .ASCIC
string, a string with the character count in byte 0)
and was originally introduced to provide information
for use by VMSINSTAL patch kits to determine whether an
image should be replaced or not.
Starting with OpenVMS Alpha V7.1-2, OpenVMS Engineering
uses the PCSI utility to package and install ECO kits
for OpenVMS. PCSI uses the generation attribute (a
32-bit unsigned integer) specified for files in the
product description file (PDF) of a PCSI kit as the
basis for performing file conflict detection and
resolution. When a product is installed, PCSI modifies
the build ident field of Alpha image headers to store
an encoded form of the generation number. It also looks
at the build ident field of previously installed images
to obtain the generation information for those files as
input to the file conflict processing algorithm. (Only
images have this field, obviously.)
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PCSI interprets the build ident field of a previously
installed image as follows:
o if the string length is 15, the 5th character is
a hyphen, and the last ten characters are a ten
digit number with leading zeros, then the last ten
characters are treated as a valid generation number.
o for V7.1-2 through V7.2-1, inclusive, if the above
test fails, the information is obtained from the
PCSI product database.
o in releases after V7.2-1 and with current PCSI ECO
kits, if the above test fails, an invalid generation
number is treated as 0000000000 so that the ECO kit
will simply replace the image rather than assuming
the PCSI database is in error.
So, what will you see in the image identification
displayed via the ANALYZE/IMAGE command?
For an image that has been built as part of an OpenVMS
Engineering system build, you will generally see a
build ID string in the format "X6TE-SSB-0000"-X6TE is
the build number for the OpenVMS Alpha V7.2-1 release.
This id format is used within the OpenVMS system build,
and can generally only be seen associated with images
that have not yet been processed via PCSI.
During the installation of V7.2-1, PCSI will modify
the image header to have a build ident string of
"X6TE-0050120000". During installation of an ECO
kit containing this image with a generation number
of 50130052, for example, PCSI would determine that
50130052 is greater than 50120000, and will replace the
existing image on the target disk with the version of
the image included in the ECO kit.
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__________________________________________________________
5.28 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,
respectively.
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.
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
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__________________________________________________________
5.29 What file checksum tools are available for OpenVMS?
The undocumented DCL command CHECKSUM is the usual
means, and provides a rather simple-minded checksum
suitable to detect basic file corruptions. For
information and an OpenVMS version of the MD5 checksum
tool, see:
o
http://www.support.compaq.com/svctools/md5-
instructions.html
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
$ SHOW SYMBOL CHECKSUM$CHECKSUM
See Section 5.16 for information on acquiring OpenVMS
ECO (patch) kits.
__________________________________________________________
5.30 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:
o
http://www.openvms.compaq.com/openvms/products/argus/
__________________________________________________________
5.31 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
tool:
$ DEFRAG SHOW/VOLUME ddcu:
The DFU tool available on the OpenVMS Freeware can
generate a report on the disk fragmentation:
DFU> REPORT ddcu:
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System Management Information
__________________________________________________________
5.32 SYSBOOT-I-FILENOTLOC, Unable to locate SYS$CPU_ROUTINES?
A message at the OpenVMS Alpha bootstrap such as the
following:
%SYSBOOT-I-FILENOTLOC, Unable to locate SYS$CPU_ROUTINES_1C02.EXE
%SYSBOOT-E-LDFAIL, failed to load execlet, status = 00000910
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 14.4.4.1.
__________________________________________________________
5.33 How can I customize the DCPS device control for a new
printer?
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.)
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o rename each extracted setup module to a
corresponding:
LPS$$UNRECOGNIZED_*
o Insert all of the above-renamed setup modules into a
newly-created device control library specific to the
new printer:
$ LIBRARY/TEXT/CREATE -
SYS$COMMON:[SYSLIB]HP4050_DEVCTL.TLB
LPS$$UNRECOGNIZED*
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$LIBRARY:HP4050_DEVCTL.TLB, -
SYS$LIBRARY:DCPS$DEVCTL.TLB
o Supply DCPS_HP4050_LIB as the library parameter
in the queue startup for this printer, this
is the P3 parameter to the command procedure
SYS$STARTUP:DCPS$EXECUTION_QUEUE.COM.
o The HP4050_DEVCTL library may/will need to be
recreated and modules re-edited and replaced with
each DCPS upgrade, particularly if any modules
are updated in the original library. You will also
want to determine if the upgraded version of DCPS
directly supports the particular printer.
o To customize the processing of file extensions
within DCPS (to enable or disable graybar output,
for instance), use the information available in:
SYS$LIBRARY:DCPS$FILE_EXTENSION_DATA_TYPE.DAT_DEFAULT
to create your own site-specific:
SYS$LIBRARY:DCPS$FILE_EXTENSION_DATA_TYPE.DAT
Also see Section 5.14.
5-39
System Management Information
__________________________________________________________
5.34 Why do $GETDEV MOUNTCNT and SHOW DEVICE mount counts
differ?
MOUNTCNT returns the local mount count, while SHOW
DEVICE returns the cluster-wide mount count.
__________________________________________________________
5.35 What software is needed for Postscript printers?
The NorthLake PrintKit (
http://www.nls.com/)
and DECprint Supervisor (DCPS;
http://www.openvms.compaq.com/openvms/Print/print_
sw_prods.html) 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.
__________________________________________________________
5.36 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
implemented.
The following is the supported mechanism to remove a
PCSI patch kit.
1 Execute a PRODUCT SHOW PRODUCE <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.
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System Management Information
4 Re-install all the patches in the list from step 1,
except those patches which you have determined you
do not want.
The above information also applies to PCSI PARTIAL
kits.
__________________________________________________________
5.37 SYSINIT-E, error mounting system device, status=0072832C
This message can arise during an OpenVMS system
bootstrap...
%MOUNT-F-DIFVOLMNT, different volume already mounted on this device
For details and further information, use the DCL
command:
$ HELP/MESSAGE /STATUS=%X72832C
__________________________________________________________
5.38 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.
5-41
System Management Information
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.)
You can display license failures by defining the
following logical name:
$ DEFINE/SYS/EXEC LMF$DISPLAY_OPCOM_MESSAGE TRUE
Enable your terminal as a license operator
(REPLY/ENABLE=LICENSE), define the LMF$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.
Note: that there is no license check failure does NOT
indicate that the particular product or operation is
permissible per the license.
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 5.5 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 12.5 for licensing and troubleshooting
information.
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:
o
http://www.compaq.com/products/software/info/
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System Management Information
__________________________________________________________
5.39 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
WRITE
$ 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 = " "
update
exit
$ Exit
Then reboot the system at your leisure.
__________________________________________________________
5.40 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$PASSWORD_DICTIONARY.DATA), and details
of how to merge your list of prohibited passwords
into the database, please see the associated chapter
in the OpenVMS security manual. For details of the
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password expiration mechanism, see the AUTHORIZE
command qualifier /PWDEXPIRED.
You can also implement a site-specific password filter
with the information provided in the back of the
OpenVMS Programming Concepts manual. The password
filter permits you to establish particular and site-
specific password requirements. For details, please
see the system parameter LOAD_PWD_POLICY and the
programming concepts manual, and see the examples in
SYS$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.
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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 $ACM on V7.3-1 and later is
recommended.)
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 expected 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 5.5 and/or the OpenVMS documentation set.
Also please see the C2 guidelines in the OpenVMS
security manual.
__________________________________________________________
5.41__Please_help_me_with_the OpenVMS BACKUP utility?
5.41.1 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.
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System Management Information
_____________________________
5.41.1.1 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 5.41.1.
_____________________________
5.41.1.2 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.
_____________________________
5.41.2 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 V6.2 release notes for additional
details.
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System Management Information
_____________________________
5.41.3 Why is BACKUP not working as expected?
First, PLEASE READ THE BACKUP MANUAL.
Second, PLEASE GET THE CURRENT BACKUP ECO KIT.
Third, PLEASE SET THE PROCESS QUOTAS PER THE
DOCUMENTATION.
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
restoration.
Without the inclusion of these apparently-extra
files, an incremental saveset can NOT be reliably
restored.
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.
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.
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System Management Information
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
versions.
_____________________________
5.41.4 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
corruptions.
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System Management Information
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:
$ @RESET_BACKUP_SAVESET_FILE_ATTRIBUTES.COM
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
options.)
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
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.
5-49
System Management Information
_____________________________
5.41.5 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:
RECORD
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
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.
5-50
System Management Information
_____________________________
5.41.6 How to perform a 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. While initially easy, characteristics of
the media and of the device error recovery and bad
block handling can make this effort far more difficult
than it might initially appear.
Security and sensitivity of the data is central to this
discussion, as is the value of the storage hardware
involved-with data of greater value than the disks
involved, physical destruction of the platters may
be the most expedient, economical, and appropriate
approach.
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 topics such as
(841), (3926), (4286), (4598), and (7320).
_____________________________
5.41.7 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:
$ DEFINE/SYSTEM/EXECUTIVE TCPIP$RLOGIN_VTA TRUE
$ DEFINE/SYSTEM/EXECUTIVE TCPIP$TELNET_VTA TRUE
See SYS$STARTUP:SYLOGICALS.TEMPLATE for details on the
typical contents of SYLOGICALS.COM.
In SYSTARTUP_VMS.COM, ensure that a command similar to
the following is invoked:
$ SYSMAN IO CONNECT VTA0/NOADAPTER/DRIVER=SYS$LOADABLE_IMAGES:SYS$TTDRIVER.EXE
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
5-51
System Management Information
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
UCX> SET CONF COMM/REMOTE=VIRTUAL
5-52
_______________________________________________________
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?
6-1
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
http://www.process.com/
o
http://www.agh.cc.kcl.ac.uk/files/vms/pine-vms/
o
ftp://ftp2.kcl.ac.uk/pub/vms/pine-vms/
o If you are working from an X11 server, 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:
o
http://seqaxp.bio.caltech.edu/pub/SOFTWARE/mmail.com
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.
6-2
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),-
F$CVUI(8,8,MY_ADDRESS_LONG),F$CVUI(16,8,MY_ADDRESS_LONG),-
F$CVUI(24,8,MY_ADDRESS_LONG))'"
$ MY_ADDRESS_REVERSE=F$FAO("!UB.!UB.!UB.!UB",-
F$CVUI(24,8,MY_ADDRESS_LONG),F$CVUI(16,8,MY_ADDRESS_LONG),-
F$CVUI(8,8,MY_ADDRESS_LONG),F$CVUI(0,8,MY_ADDRESS_LONG))'"
$ WRITE SYS$OUTPUT F$TIME()+" "+F$TRNLNM("SYS$REM_NODE")+MY_ADDRESS
$ UCX SHOW HOST 'MY_ADDRESS_REVERSE'.INPUTS.ORBS.ORG
$ IF $STATUS.EQ.1
$ THEN
$ WRITE SYS$OUTPUT "SPAM from relay rejected"
$ EXIT
$ ENDIF
$ UCX SHOW HOST 'MY_ADDRESS_REVERSE'.SPAMSOURCES.ORBS.ORG
$ 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
6-3
_______________________________________________________
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
(www.openvms.compaq.com/freeware/dqdriver/), and these
updates are also included on OpenVMS Freeware V5.0,
and OpenVMS ECO kits containing newer versions of the
driver are available.
OpenVMS Alpha V7.3 and later include a version of
SYS$DQDRIVER with the necessary IO$_DIAGNOSE support.
7-1
Information on Utilities
__________________________________________________________
7.2 How do I access a Microsoft Windows floppy disk from
OpenVMS?
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.
ProGIS in Germany sells a product called VMove which
supports DOS files on many different device types. For
more information, send mail to
[email protected].
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
[email protected] 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.
o
http://www.madgoat.com/
__________________________________________________________
7.3 How do I play sound files on an AlphaStation? DECsound
doesn't work.
The new 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. HP offers
an optional product, Multimedia Services for OpenVMS:
o
http://www.compaq.com/info/spd/
OpenVMS typically uses SPD 25.01.xx and/or SPD
41.87.xx.
which provides a replacement 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.
7-2
Information on Utilities
__________________________________________________________
7.4 Why is DECmigrate not working with Fortran?
%OTS-F-INDATCOR internal data corrupted in Run-
time Library
This error can arise with Fortran programs if you are
running a recent version of OpenVMS Alpha, and are
using DECmigrate to translate Fortran applications. The
DECmigrate Run-Time Library attempts to support mixed
translated-native I/O to the same unit by sharing the
native Fortran RTL's internal data structures, and in
OpenVMS 7.2 these structures changed and the translated
RTL was not updated accordingly.
You can copy DEC$FORRTL.EXE from OpenVMS 7.1, copying
it to some spare directory, and then defining the
logical name DEC$FORRTL to point to it before running
your translated application. Or rebuilding the
application to use the available native Fortran
compiler. Or you can apply the current Fortran RTL
kit, which has a fix for this.
See Section 13.11.
__________________________________________________________
7.5 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
language.
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 (via
http://www.decus.org/),
and search for "EBCDIC" for details.
OpenVMS does not include an integrated tool for
EBCDIC tape processing, but does provide a character
conversion API useful within application programs.
7-3
Information on Utilities
One source for ETAPE is:
o
http://www.ualr.edu/ftp/vms/ETAPE_SRC/
The OpenVMS Freeware V5.0 distribution included this
ETAPE tool, as well.
__________________________________________________________
7.6 How can I patch an OpenVMS Alpha image?
Using the OpenVMS Freeware tool ZAP:
o www.openvms.compaq.com/freeware/freeware50/rms_
tools/
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.
7-4
_______________________________________________________
8 DCL Details
__________________________________________________________
8.1 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". For example:
$ unzip :== $disk:[dir]unzip.exe
$ unzip -?
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
8-1
DCL Details
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
$ RUN/DETACHED SYS$SYSTEM:LOGINOUT /INPUT=TEMP_INPUT.COM
Various OpenVMS library calls (such as lib$spawn(),
cli$dcl_parse(), and the C library system() call)
require access to a command line interpreter such as
DCL to perform requested actions, and will not operate
if a CLI is not available.
When a CLI is not available, these calls typically
return the error status SS$_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
SYS$STARTUP:TCPIP$DEFINE_COMMANDS.COM.
Also see Section 8.10.
__________________________________________________________
8.2 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
LOGIN.COM:
$ CLS :== TYPE/PAGE NLA0:
__________________________________________________________
8.3 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:
8-2
DCL Details
$ 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
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
OPERATOR.LOG.
__________________________________________________________
8.4 How do I generate a random number in DCL?
Here is a 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).
8-3
DCL Details
$! RAND - returns a positive random number ("RANDOM") between 0 and
$! __CEIL - 1.
$! sharris-at-sdsdmvax.fb3.noaa.gov
$ 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
$
$ __SEED == __SEED * 69069 + 1
$
$ RANDOM == (__SEED.AND.%X3FFFFFFF)/(%X40000000/__CEIL)
$
$ RETURN
__________________________________________________________
8.5 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
8-4
DCL Details
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 8.1.
__________________________________________________________
8.6 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
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
ftp://ftp.hhs.dk/pub/vms/setpmt/
8-5
DCL Details
o
ftp://ftp.tmesis.com/sys_service_hook.src
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.
__________________________________________________________
8.7 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:
o
http://www.openvms.compaq.com/wizard/
o
http://www.openvms.compaq.com/wizard/wizard.zip
For additional information, please see Section 3.9.
DCL does not include support asynchronous I/O, thus a
predetermined protocol or a predetermined "turn-around"
command sequence must be implemented in order to avoid
protocol deadlocks-cases where both tasks are trying to
write or both tasks are trying to read. The task that
is writing messages to the network must write (or write
and read) a predetermined sequence of messages, or it
must write a message that tells the reader that it can
now start writing messages. (This is the essence of a
basic half-duplex network protocol scheme.)
__________________________________________________________
8.8 How can I get the width setting of a terminal?
$ width = f$getdvi(terminal,"DEVBUFSIZ")
8-6
DCL Details
__________________________________________________________
8.9 How can I substitute symbols in a PIPE?
Use DCL ampersand substitution, and not apostrophe
substitution.
$ pipe show system | search sys$input opcom | (read sys$input pid ;
pid=f$element(0," ",pid) ; define/system opcom_pid &pid)
$ show log opcom_pid
"OPCOM_PID" = "0000020B" (LNM$SYSTEM_TABLE)
__________________________________________________________
8.10 Use of RUN/DETACH, LOGINOUT, and logical names?
With a command to create a detached process such as:
$ RUN/DETACHED SYS$SYSTEM:LOGINOUT /INPUT=TEMP_INPUT.COM
If you are trying to use a logical name as the /INPUT,
/OUTPUT or /ERROR on a RUN/DETACH command, then
you must translate the logical name specifications
to physical references before passing them, or the
definitions must reside in a logical name table that is
visible to the newly-created process.
Also note that LOGINOUT only creates the SYS$LOGIN,
SYS$LOGIN_DEVICE, and SYS$SCRATCH logical names if it
is processing a login that is based on the contents of
a SYSUAF record-without access to the associated SYSUAF
record, this information is not available to LOGINOUT.
(If you want to see these particular logical names
created, then please specify the /AUTHORIZE qualifier
on the RUN/DETACHED command.)
If you do not specify LOGINOUT as the image, then
there is no easy way to get these logical names. Also,
any logical names that are used in the target image
file specification must also be in a logical name
table accessible (by default) by the newly-created
detached process. Shared tables include the group (if
the process is in the same UIC group) and the system
table. (If the target process is to be in another UIC
group, a suitablly privileged user or application can
create the necessary logical name(s) directly in the
other group logical name table.)
8-7
DCL Details
When in doubt, create a short DCL command file as
input, and use a SHOW LOGICAL and similar commands
to examine the context. (And use physical device and
directory references on the RUN/DETACH of the LOGINOUT
image, when specifying this command file as /INPUT.)
Also remember to check both security auditing and
system accounting when troubleshooting problems with
the RUN/DETACH.
Also see Section 8.1.
__________________________________________________________
8.11 How to use escape and control characters in DCL?
To write a message and then the bell character, use:
$ bell[0,7] = 7
$ write sys$output "Hello''bell'"
To write blinking text, use:
$ esc[0,7] = 27
$ text = "Blinking Text"
$ write sys$output "''esc'[5m''text'''esc'[m"
Also see sections Section 11.7, Section 12.1.
8-8
_______________________________________________________
9 Files
__________________________________________________________
9.1 How can I undelete a file?
OpenVMS doesn't have an "undelete" function. However,
if you are quick to write-protect the disk or if you
can guarantee that no new files get created or existing
files extended, your data is still on the disk and
it may be possible to retrieve it. The FLORIAN tool
available from various websites can potentially recover
the file, see question Section 13.1 for pointers. Other
alternatives here include the DFU tool, available on
the OpenVMS Freeware CD-ROM distribution.
If you are setting up a user environment for yourself
or for others, it is quite easy to use DCL to intercept
the DELETE command, using a symbol:
$ DEL*ETE :== @SYS$LOGIN:MYDELETE.COM
The DELETE symbol will cause the procedure to
be invoked whenever the user enters the DELETE
command, and it can copy the file(s) to a "trashcan"
subdirectory before issuing a "real" DELETE on the
files. Other procedures can retrieve the file(s) from
the "trashcan" subdirectory, and can (and should) clean
out the "trashcan" as appropriate. (Realize that this
DELETE symbol can interfere with DELETE/GLOBAL and
other similar DCL commands.)
__________________________________________________________
9.2 Why does SHOW QUOTA give a different answer than DIR/SIZE?
DIRECTORY/SIZE doesn't take into account the size of
file headers which are charged to your quota. Also,
unless you use DIRECTORY/SIZE:ALL, you will see only
the "used" size of the file, not the allocated size
which is what gets charged against your quota. Also,
you may have files in other directories.
9-1
Files
$ DIRECTORY/SIZE=ALL/GRAND [username...]
Grand total of D1 directories, F1 files, B1/B2 blocks.
$ DIRECTORY/SIZZ=ALL/GRAND [-]username.DIR
Grand total of 1 directory, 1 file, B3/B4 blocks.
$ SHOW QUOTA
User [username] has B5 blocks used, B6 available
of B7 authorized and permitted overdraft of B8 blocks on disk
If the user has no files in other directories and
all file-headers are only 1 block, then the following
should apply:
B5=B2+B4+F1+1
If the diskquota has drifted out of synchronization,
then the system-manager can force a quota rebuild-due
to various factors, the quota file can potentially
drift from the actual use over time, and a periodic
rebuild can be performed at appropriate intervals.
Also be aware that the DIRECTORY/SIZE command can
report larger values than might otherwise be expected
when used to evaluate files and/or directories that
are alias links-such as the system roots on OpenVMS
system disks-as the command reports a total that
is cumulative over all of the files and directories
examined, without regard for which ones might be
alias entries and which are not. (In other words, a
DIRECTORY/SIZE of an entire OpenVMS system disk will
report a disk useage value larger than the (usually
more accurate) value reported by the SHOW DEVICE
command. This as a result of the alias entries linking
each SYS$SYSDEVICE:[SYSCOMMON]SYS*.DIR directory file
and the SYS$SYSDEVICE:[000000]VMS$COMMON.DIR file
together.)
__________________________________________________________
9.3 How do I make sure that my data is safely written to disk?
If your application must absolutely guarantee that
data is available, no matter what, there's really no
substitute for RMS Journaling and host- or controller-
based shadowing. However, you can achieve a good degree
of data integrity by issuing a SYS$FLUSH RMS call at
appropriate times (if you're using RMS, that is.) If
you're using a high-level language's I/O system, check
9-2
Files
that language's documentation to see if you can access
the RMS control blocks for the open file. In C you can
use fflush followed by fsync.
For details on disk bad block handling on MSCP and
on SCSI disk devices, please see Ask The Wizard (ATW)
topic (6926).
o
http://www.openvms.compaq.com/wizard/
o
http://www.openvms.compaq.com/wizard/wizard.zip
For additional information, please see Section 3.9.
__________________________________________________________
9.4 What are the limits on file specifications and directories?
A file specification has an aggregate maximum size
of 255 characters at present. The node and device
specification may be up to 255 characters each -
file name and file types may be up to 39 characters
each. File versions are from 1 through 32767, though
0 (latest version), -0 (oldest version) and -n (n'th
previous version) can be used in most contexts. A file
specification may not have more than 8 directories
and subdirectories - while it is possible to create
subdirectories of greater depth, accessing them is
problematic in most cases and this should be avoided.
Application developers should use OpenVMS-supplied
routines for parsing file specifications - this ensures
that changes in what is allowable will not tend to
break your application. Consider that various parts of
the file specification may contain quoted strings with
embedded spaces and other punctuation! Some routines
of interest are SYS$FILESCAN, SYS$PARSE and LIB$TRIM_
FILESPEC. For further information, see the OpenVMS
Guide to File Applications.
Performance of larger directory files improves
(greatly) with OpenVMS V7.2 and later-operations on
directory files of 128 blocks and larger were rather
slower on earlier OpenVMS releases due to the smaller
size of the directory cache and due to the directory
I/O processing logic.
9-3
Files
For fastest directory deletions, consider a reverse
deletion-delete from the last file in the directory to
the first. This reversal speeds the deletion operation
by avoiding unnecessary directory I/O operations as
the files are deleted. Tools such as the Freeware DFU
can be used for this purpose, as can various available
reverse-DELETE DCL command procedures.
__________________________________________________________
9.5 What is the largest disk volume size OpenVMS can access?
One Terabyte (TB; 2**31 blocks of 2**9 bytes;
0x07FFFFFFF blocks). 255 volumes in a volume set.
The largest contiguous allocation possible for any
particular file is 0x03FFFFFFF blocks.
Prior to the release of V6.0, the OpenVMS file system
was limited to disk volumes of 8.38 GB (2**24 blocks,
16777216 blocks) or less.
On some systems, there are restrictions in the console
program that limit the size of the OpenVMS system disk.
Note that data disks are not affected by console
program limits. For example, all members of the
VAXstation 3100 series are limited to a system disk
to 1.073 GB or less due to the console, though larger
data disks are possible. This limit due to the SCSI
drivers used by and built into the console ROM to read
the OpenVMS bootstrap files, and these same drivers are
also used by OpenVMS to write the system crashump.
There are numerous discussions of this VAXstation
3100 in the comp.os.vms newsgroup archives. Please
use Google newsgroup search to search the archives for
further details, for discussions of the workarounds,
and for details of the potential for a simple failed
bootstrap and particularly for discussions of the
potential for severe system disk corruptions on
crashes.
Some SCSI disks with capacities larger than 8.58
gigabytes (GB) will require the use of an OpenVMS ECO
kit (eg: ALPSCSI04_062 or later; see Section 14.26
for details) for new SCSI device drivers. Failure to
use this ECO can cause "rounding errors" on the SCSI
disk device capacity-OpenVMS will not use nor display
9-4
Files
the full capacity of the drive-and "%sysinit-e-error
mounting system device status equals 000008C4" (8C4
-> "%SYSTEM-?-FILESTRUCT, unsupported file structure
level") errors during bootstrap. (One workaround for
the bootstrap when the bitmap is located far into the
disk is the use of INIT/INDEX=BEGIN.) The problem here
involves the particular extensions and fields used for
larger capacity disks within the SCSI specifications
and within the various intepretations of same.
For ATA (IDE) disk drives:
o Versions of SYS$DQDRIVER *BEFORE* X-15 topped out at
8.455 GB.
Fixed drivers (equal or greater than "X-15") were
shipped in:
o OpenVMS Alpha V7.2-1, and later
o V7.2 UPDATE V1.0 ECO, and later
o V7.1-2 UPDATE V1.0 ECO, and later
o V7.1-2 UPDATE V3.0 ECO, and later
o The newer SYS$DQDRIVER driver operates to disks up
to 33 GB without (known) problems, and effectively
works with rather larger disks (up to circa 137
GB) but is known to report an incorrect number of
"cylinders" with disks above 33 GB.
See Section 14.4.4.2 for additional ATA SYS$DQDRIVER
information.
Be aware that a known restriction in certain older
versions of the Alpha SRM Console prevents booting most
ATA (IDE) drives larger than 8.455 GB, depending on
exactly where the various files are located on the
volume. Updated SRM consoles for systems with SRM
and ATA (IDE) drive support are (will be) available.
(OpenVMS Engineering has successfully bootstrapped
20GB ATA (IDE) disks using the appropriate SRM console
version.)
9-5
---------------------------- #include <rtfaq.h> -----------------------------
For additional, please see the OpenVMS FAQ -- www.hp.com/go/openvms/faq
--------------------------- pure personal opinion ---------------------------
Hoff (Stephen) Hoffman OpenVMS Engineering hoff[at]hp.com
