The OpenNET Project / Index page

[ новости /+++ | форум | wiki | теги | ]

Поиск:  Каталог документации | DEC

OpenVMS Frequently Asked Questions (FAQ), Part 1/5

This posting contains answers to frequently asked questions about the OpenVMS operating system from Compaq Computer Corporation, and the computer systems on which it runs.
Archive-name: dec-faq/vms/part1
Posting-Frequency: quarterly
Last-modified: 2 Oct 2001
Version: VMS-FAQ-1.TXT(7)

Changes since last edition
Numerous URL and minor text updates, plus...
Add DOC13        What OpenVMS mailing lists are available?
Add DOC14        What is this Ask The Wizard website I've heard about?
Update INTRO8    reflect organizational changes
Add ITAN1        OpenVMS is porting to Intel IA-64?
Add ITAN2        Where can I get Intel Itanium information?
Add MAIL10       How can I block SMTP mail relay spam?
Add MISC22       How do I convert?  Disk Blocks?  KB, MB, GB, TB?
Update MGMT3     VMS File System Internals book reportedly out of print
Update MGMT14    sub/STS/SYS/
Update MGMT16    Add V7.3 to upgrade paths
Add MGMT61       Explain disk (or tape) allocation class settings?
Add MGMT62       How to prevent users from choosing obvious passwords?
Add MGMT63       Volume Shadowing MiniCopy vs MiniMerge?
Add MGMT64       Why is BACKUP not working as expected?
Add PROG22       Dealing with Endian-ness?
Add PROG23       How to resolve LINK-I-DATMISCH errors?
Update SOFT1     XPDF, etc
Update SOFT4     Tomcat, etc
Update SOFT5     sequence points, argument evaluation
Add TIME13       Customizing your TDF (Timezone) Setting?
Add VMS17        memory management, resource management, ...

This is part 1/5 of the Frequently Asked Questions (FAQ) posting for 
the comp.os.vms and comp.sys.dec newsgroups.  (comp.os.vms is
bidirectionally-gatewayed to the INFO-VAX mailing list - see INTRO3
for further details.)  It contains answers to frequently asked
questions about Compaq's OpenVMS operating system and the computer
systems on which it runs.  (Please see INTRO5 before posting.)

Table of Contents - Part 1/5

OV1.     Overview of the OpenVMS FAQ, Updates, Editor, Contact Info

INTRO1.  What is the scope of comp.os.vms?
INTRO2.  What other newsgroups carry VMS-related information?
INTRO3.  What is INFO-VAX?
INTRO4.  How do I subscribe to or unsubscribe from INFO-VAX?
INTRO5.  How do I submit a question or a response?  What is etiquette?
INTRO6.  What is Encompass (DECUS)?
INTRO7.  What archives of comp.os.vms/INFO-VAX are available?
INTRO8.  Who are the corporate contacts for OpenVMS business issues?

General questions about OpenVMS
VMS1.   What is OpenVMS?  What is its history?
VMS2.   What is the difference between VMS and OpenVMS?
VMS3.   How do I port from VMS to OpenVMS?
VMS4.   Which is better - OpenVMS or UNIX?
VMS5.   Is Compaq continuing funding and support for OpenVMS?
VMS7.   What OpenVMS CD-ROM products are available?
VMS8.   In what language is OpenVMS written?
VMS9.   How do I obtain or transfer a VMS license?
VMS10.  What is OpenVMS doing about the Euro currency symbol?
VMS11.  Why hasn't OpenVMS been ported to Intel (IA32) systems?
VMS12.  Are there any general-access OpenVMS systems available?
VMS13.  What version of OpenVMS do I need?
VMS14.  How can I submit OpenVMS Freeware?
VMS15.  Porting applications to OpenVMS?
VMS16.  How do I join Compaq Solutions Alliance?
VMS17.  memory management, resource management, process scheduling, etc?

Documentation and other resources
DOC1.   Where can I find online copies of OpenVMS manuals?
DOC2.   What online information is available?
DOC3.   What books and publications are available?
DOC4.   How do I extract a HELP topic to a text file?
DOC5.   Does OpenVMS Marketing have an e-mail address?
DOC6.   What OpenVMS-related WWW sites are available?
DOC8.   Where can I find info about undocumented OpenVMS features?
DOC9.   Where is documentation on the DECnet Phase IV protocols?
DOC10.  Where can I learn about how the VMS executive works internally?
DOC11.  Where can new users find tutorial information about OpenVMS?
DOC12.  How to access the OpenVMS Netscape Navigator documentation?
DOC13.  What OpenVMS mailing lists are available?
DOC14.  What is this Ask The Wizard website I've heard about?

OpenVMS System Time
TIME1.   A brief history of OpenVMS Timekeeping, please?
TIME2.   How does OpenVMS VAX maintain system time?
TIME3.   Why does my system time drift?
TIME4.   Managing Timezones, Timekeeping, UTC, and Daylight Savings?
TIME5.   How to troubleshoot TDF problems on OpenVMS?
TIME6.   How can I keep the OpenVMS system time synchronized?
TIME7.   How can I configure TCP/IP Services NTP as a time provider?
TIME8.   How can I drift the OpenVMS system time?
TIME9.   Why does VAX need a SET TIME at least once a year?
TIME10.  Why can't I do a SET TIME command?  Help managing DTSS?
TIME11.  Details of the OpenVMS system time-keeping?
TIME12.  UTC vs GMT vs vs UT1/UT1/UT2 TDF?  What are these acronyms?
TIME13.  Customizing your TDF (Timezone) Setting?

Table of Contents - Part 2/5

System Management
MGMT1.  What is an installed image?
MGMT2.  Are there any known viruses for OpenVMS?
MGMT3.  How do I mount an ISO-9660 CD on OpenVMS?
MGMT4.  How do I extract the contents of a PCSI kit?
MGMT5.  I've forgotten the SYSTEM password - what can I do?
MGMT6.  How do I connect a PostScript printer via TCP/IP?
MGMT9.  How do I change the node name of an OpenVMS System?
MGMT10. What is the correct value for EXPECTED_VOTES in a VMScluster?
MGMT11. Why doesn't OpenVMS see the new memory I just added?
MGMT12. How do I write a BACKUP saveset to a remote tape?
MGMT13. Tell me about SET HOST/DUP and SET HOST/HSC
MGMT14. How do I install DECnet Phase IV on VMS 7.1?
MGMT15. How do I change the text in a user's UIC identifier?
MGMT16. What are the OpenVMS version upgrade paths?
MGMT17. Why do I have negative number in the pagefile reservable pages?
MGMT18. Do I have to update layered products when updating OpenVMS?
MGMT19. How do I change the volume label of a disk?
MGMT20. How do I fix a corrupt BACKUP saveset?
MGMT21. How can I set up a shared directory?
MGMT23. Why do I get extra blank pages on my HP Printer?
MGMT24. How do I configure ELSA GLoria Synergy graphics on OpenVMS?
MGMT25. How do I acquire OpenVMS patches, fixes, and ECOs?
MGMT26. How do I rename a DSSI disk (or tape?)
MGMT27. How do I move the queue manager database?
MGMT28. How do I set a default IP route or gateway on OpenVMS?
MGMT30. How do I delete an undeletable/unstoppable (RWAST) process?
MGMT31. How do I reset the error count(s)?
MGMT32. How do I find out if the tape drive supports compression?
MGMT33. Can I copy SYSUAF to another version? To VAX? To Alpha?
MGMT34. How do I delete (timeout) idle processes?
MGMT35. Why isn't BACKUP/SINCE=BACKUP working?
MGMT36. How can I set up reverse telnet (like reverse LAT)?
MGMT37. Do I need a PAK for the DECevent (Compaq Analyze) tool?
MGMT38. INITIALIZE ACCVIO and ANSI tape label support?
MGMT39. How do I recover from INSVIRMEM errors?
MGMT40. How can I prevent a serial terminal line from initiating a login?
MGMT41. How does PCSI use the image BUILD_IDENT field?
MGMT42. How to configure allocation classes and Multi-Path SCSI?
MGMT43. How can I tell what software (and version) is installed?
MGMT44. Where can I get Fibre Channel Storage (SAN) information?
MGMT45. How can I split up an OpenVMS Cluster?
MGMT46. What file checksum tools are available for OpenVMS?
MGMT47. Configuring Cluster SCS for path load balancing?
MGMT48. What (and where) is the OpenVMS Management Station?
MGMT49. Determining disk fragmentation level?
MGMT51. How can I customize the DCPS device control for a new printer?
MGMT52. Why do $GETDEV MOUNTCNT and SHOW DEVICE mount counts differ?
MGMT53. What software is needed for Postscript printers?
MGMT54. Does volume shadowing require a non-zero allocation classes?
MGMT56. How do I remove a PCSI-installed patch (ECO) kit?
MGMT57. SYSINIT-E, error mounting system device, status=0072832C
MGMT58. Performing SET HOST/MOP in DECnet-Plus?
MGMT59. Resolving License PAK Problems?

Table of Contents - Part 3/5

MGMT (Continued)

MGMT60. Changing the OpenVMS Version Number?
MGMT61. Explain disk (or tape) allocation class settings?
MGMT62. How to prevent users from choosing obvious passwords?
MGMT63. Volume Shadowing MiniCopy vs MiniMerge?
MGMT64. Why is BACKUP not working as expected?

MAIL1.  How do I send Internet mail?
MAIL2.  How do I get IN% or MX% added automatically to Internet addresses?
MAIL3.  How do I automatically append a signature file to my mail messages?
MAIL4.  Do I have to use VMS MAIL?  I like my Unix mailer better.
MAIL5.  How can I forward my mail?  Can I forward it to an Internet address?
MAIL6.  How can I forward my mail to a list of addresses?
MAIL7.  MAIL keeps saying I have new messages, but I don't.  What do I do?
MAIL8.  How do I extract all of my mail messages to a file?
MAIL9.  How do I send or read attachments in VMS MAIL?
MAIL10. How can I block SMTP mail relay spam?

Other Utilities
UTIL1.  How do I play an audio CD on my workstation?
UTIL2.  How do I access a MS-DOS floppy disk from OpenVMS?
UTIL3.  How do I play sound files on an AlphaStation?  DECsound doesn't work
UTIL4.  Why is DECmigrate not working with Fortran?
UTIL5.  How do I read IBM EBCDIC tapes on OpenVMS?
UTIL6.  How can I patch an OpenVMS Alpha image?

DCL and command usage
DCL1.   How do I run a program with arguments?
DCL2.   How can I redefine control keys in DCL?
DCL3.   How can I clear the screen in DCL?
DCL4.   Using REPLY/LOG from DCL?  Disabling Console OPCOMs?
DCL5.   How do I generate a random number in DCL?
DCL6.   What does the MCR command do?
DCL7.   How do I change the OpenVMS system prompt?
DCL8.   Can I do DECnet task-to-task communication with DCL?
DCL9.   How can I get the width setting of a terminal?
DCL10.  How can I substitute symbols in a PIPE?
DCL11.  Use of RUN/DETACH and logical names?
DCL12.  How to use escape and control characters in DCL?

File System and RMS
FILE1.  How can I undelete a file?
FILE2.  Why does SHOW QUOTA give a different answer than DIR/SIZE?
FILE3.  How do I make sure that my data is safely written to disk?
FILE4.  What are the limits on file specifications and directories?
FILE5.  What is the largest disk volume size OpenVMS can access?
FILE6.  What is the maximum file size, and the RMS record size limit?
FILE7.  How do I write recordable CD media (CD-R) on OpenVMS?
FILE8.  What I/O transfer size limits exist in OpenVMS?
FILE9.  Can I use ODBC to connect to OpenVMS database files?

PROG1.  How do I call <routine_name> from <language_name>?
PROG2.  How do I get the arguments from the command line?
PROG3.  How do I get a formatted error message in a variable?
PROG4.  How do I link against SYS$SYSTEM:SYS.STB on an Alpha system?
PROG5.  How do I do a SET DEFAULT from inside a program?
PROG6.  How do I create a shareable image transfer vector on an Alpha system?
PROG7.  How do I turn my Fortran COMMON into a shareable image on Alpha?
PROG8.  How do I convert between IEEE and VAX floating data?
PROG9.  How do I get the argument count in a Fortran routine?
PROG10. How do I get a unique system ID for licensing purposes?
PROG11. What is an executable, shareable, system or UWSS image?
PROG12. How do I do a file copy from a program?
PROG13. What is a descriptor?
PROG14. How many bytes are in a disk block?
PROG15. How many bytes are in a memory page?
PROG16. How do I create a process under another username?
PROG17. Why do lib$spawn, lib$set_symbol fail in detached processes?
PROG18. Where can I obtain Bliss, and the libraries and supporting files?
PROG19. How can I open a file for shared access?
PROG20. How can I have common sources for messages, constants?
PROG21. How do I activate the OpenVMS Debugger from an application?
PROG22. Dealing with Endian-ness?
PROG23. How to resolve LINK-I-DATMISCH errors?

Table of Contents - Part 4/5

DECW1.  How do I let someone else display something on my workstation?
DECW2.  How do I create a display on another workstation?
DECW3.  How can I get the information from SHOW DISPLAY into a symbol?
DECW4.  How do I get a log of a DECterm session?
DECW5.  Problem - the DELETE key deletes forward instead of backward!
DECW6.  Why is DECwindows Motif not starting?
DECW9.  How do I set the title on a DECterm window?
DECW10. How do I customize DECwindows, including the login screen?
DECW11. Why doesn't XtAppAddInput() work on OpenVMS?
DECW12. Why do the keyboard arrow keys move the DECwindows cursor?
DECW13. Why does half my DECwindows display blank?
DECW14. %DECW-W-NODEVICE, No graphics device found on this system?
DECW15. How can I reset the warning bell volume?
DECW16. How can alter the DECwindows CDE backdrop?
DECW17. How can I enable the DECwindows TCP/IP Transport

MISC2.    Where can I find information on escape and control sequences?
MISC6.    What does "failure on back translate address request" mean?
MISC7.    How to determine the network hardware address?
MISC9.    Why can't I use PPP and RAS to connect to OpenVMS Alpha?
MISC12.   Does DECprint (DCPS) work with the LRA0 parallel port?
MISC13.   How do I check for free space on a (BACKUP) tape?
MISC14.   So what happened to sys$cmsuper?
MISC15.   How can I send radio pages from my OpenVMS system?
MISC17.   How do I reset the LAN (DECnet-Plus NCL) counters?
MISC18.   What are the prefixes for the powers of ten?
MISC19.   OpenVMS Cluster (SCS) over DECnet?  Over IP?
MISC20.   Correctly using license PAKs and LMF?
MISC21.   Third-party disk/tape/controllers/SCSI/widgets on OpenVMS?
MISC22.   How do I convert?  Disk Blocks?  KB, MB, GB, TB?

SOFT1.    Where can I find freeware/shareware/software for OpenVMS?
SOFT2.    Where can I find the UNIX <whatever> tool for OpenVMS?
SOFT3.    Where can I get the Netscape Navigator Web Browser?
SOFT4.    Where can I get Java for OpenVMS?
SOFT5.    VAX C and DEC C, and other OpenVMS C Programming Considerations?
SOFT6.    Obtaining user input in DCL CGI script?
SOFT7.    How do I get my own batch entry number?
SOFT8.    How do I convert to new CMS libraries?
SOFT9.    Where can I get new certificates for Netscape Navigator?
SOFT10.   Why doesn't DCL symbol substitution work?
SOFT12.   Where can I get Perl for OpenVMS?
SOFT13.   Where can I get DECmigrate (VEST and TIE)?

Table of Contents - Part 5/5

Alpha and Alpha-based systems
ALPHA1.   What do the letters AXP stand for?
ALPHA2.   What are the OpenVMS differences between VAX and Alpha?
ALPHA5.   Seeking performance information for Alpha (and VAX) systems?
ALPHA6.   Where can I get updated console firmware for Alpha systems?
ALPHA7.   How do I boot an AlphaStation without monitor or keyboard?
ALPHA8.   Will OpenVMS run on a Multia? AlphaPC 164LX? 164SX?
ALPHA9.   What is the least expensive system that will run OpenVMS?
ALPHA10.  Where can I get more information on Alpha systems?
ALPHA11.  What are the APB boot flag values?
ALPHA12.  What are Alpha console environment variables?
ALPHA13.  Will OpenVMS run on a NoName AXPpci33?
ALPHA14.  How do I reload SRM firmware on a half-flash Alpha system?
ALPHA15.  Will OpenVMS run on the Alpha XL series?
ALPHA16.  Describe Alpha instruction emulation and instruction subsets?
ALPHA17.  What is the Accuracy of the Alpha Time of Year (BB_WATCH) Clock?
ALPHA18.  So how do I open up the DEC 3000 chassis?
ALPHA19.  What is byte swizzling?
ALPHA20.  What commands are available in the Alpha SRM console?
ALPHA21.  How do I switch between AlphaBIOS/ARC and SRM consoles?
ALPHA22.  OpenVMS on the Personal Workstation -a and -au series?
ALPHA23.  OpenVMS and Personal Workstation IDE bootstrap?
ALPHA24.  Which terminal device name is assigned to the COM ports?

VAX and VAX-based systems
VAX1.   Please explain the back panel of the MicroVAX II
VAX2.   What is the layout of the VAX floating point format?
VAX3.   Where can I find more info on VAX systems?
VAX4.   Where can I find information on NetBSD for VAX systems?
VAX5.   What system disk size limit on the MicroVAX and VAXstation 3100?
VAX7.   What are the VMB boot flag values?
VAX9.   Which serial port is the console on the MicroVAX 3100?
VAX10.  How can I set up an alternate console on a VAXstation?
VAX11.  What are the VAX processor (CPU) codes?

Intel Itanium-based systems
ITAN1.  OpenVMS is porting to Intel IA-64?
ITAN2.  Where can I get Intel Itanium information?

Hardware and Software Support resources
SUPP1.  Where can I get software and hardware support information?
SUPP2.  Where can I get hardware self-maintenance support assistance?
SUPP3.  Why does my system halt when I power-cycle the console terminal?
SUPP4.  Can I reuse old keyboards, mice and monitors with a PC?
SUPP5.  Which video monitor works with which graphics controller?
SUPP6.  Where can I get information on storage hardware?
SUPP7.  Problem - My LK401 keyboard unexpectedly autorepeats
SUPP8.  Problem - My LK411 sends the wrong keycodes or some keys are dead
SUPP9.  Which DE500 variant works with which OpenVMS version?

SCSI-related Hardware information
SCSI1.  Are the 2X-KZPCA-AA and SN-KZPCA-AA LVD Ultra2 SCSI?
SCSI2.  Resolving DRVERR fatal device error?

Wiring-, Adapter-, Connector-, and Pinout-related Hardware information
WIRES1. Looking for connector wiring pinouts?
WIRES2. What connectors and wiring adapters are available?
WIRES3. What is flow control and how does it work?

NET1.  How to connect OpenVMS to the Internet?
NET2.  How to connect OpenVMS to a Modem?

OV1.  Overview of the OpenVMS FAQ, Updates, Editor, Contact Info

  The OpenVMS FAQ is archived in the following locations:
    comp.answers and news.answers newsgroups

  Other internet FAQs are generally available in these locations:

    comp.answers and news.answers newsgroups

  User-created HTML versions of the OpenVMS FAQ are located at:

Please do NOT send technical questions to the Frequently Asked Questions 
(FAQ) editor -- well, please do not email any questions that do not also
include the answer(s).  Please post these questions to the appropriate 
newsgroup instead -- and see INTRO5 before posting.  To make suggestions 
for changes or additions to this FAQ list, please send mail to the FAQ 
editor at the address listed in the sig file.  Again, the FAQ editor is 
*not* in a position to answer general questions.

Some general notes:

The term "VMS" is synonymous with "OpenVMS".  "Alpha", "AlphaGeneration" or 
"AXP" generally refers to any system or product based on or related to 
Compaq's Alpha processor architecture.  OpenVMS manual names mentioned are
those as of V7.2 -- names may be different in other editions of the
documentation set.

World-Wide Web Universal Resource Locator (URL) notation is used for FTP

Many people have contributed to this list, directly or indirectly.  In
some cases, an answer has been adapted from one or more postings on the
comp.os.vms newsgroup.  Our thanks to all of those who post answers.
The name (or names) at the end of an entry indicate that the information
was taken from postings by those individuals; the text may have been
edited for this FAQ.  These citations are only given to acknowledge the

Although the editor of this FAQ is an employee of Compaq Computer
Corporation, this posting is not an official statement of Compaq.

AlphaGeneration, AlphaServer, AlphaStation, Alpha AXP, AXP, DEC, DECstation,
DECsystem, OpenVMS, ULTRIX, VAX and VMS are trademarks of Compaq.  Compaq 
and the names of Compaq products are trademarks and/or registered trademarks 
and/or service marks of Compaq Computer Corporation.  OSF/1 is a registered 
trademark of the Open Software Foundation.  UNIX is a registered trademark 
in the United States and other countries, licensed exclusively through 
X/Open Company Ltd.  Other names are properties of their respective owners.

INTRO1.  What is the scope of comp.os.vms?

The comp.os.vms newsgroup is the primary newsgroup for discussion of 
Compaq's OpenVMS operating system and the computer systems on which it
runs.  Questions about layered products which run on OpenVMS are also
welcome, though many of them (in particular, language compilers and
database systems) have more specific newsgroups.  If a question has
some relationship to OpenVMS, it belongs here.

INTRO2.  What other newsgroups carry VMS-related information?

The vmsnet.* hierarchy, run by DECUS, contains several newsgroups of
interest, including vmsnet.misc and vmsnet.alpha, the latter being mostly
devoted to Alpha topics.  There's also vmsnet.sources (and 
vmsnet.sources.d) to which sources for or pointers to freeware are posted.
See the separate "What is VMSNET" monthly posting for further details.

Sprechen Sie Deutsch? Besuchen Sie bitte den newsgroup de.comp.os.vms. 

The comp.sys.dec newsgroup carries general discussions about various Compaq 
computer systems, and specifically systems that were acquired by Compaq as 
part of the acquisition of Digital Equipment Corporation (DEC).

INTRO3.  What is INFO-VAX?

INFO-VAX is a mailing list which is bidirectionally gatewayed to the
comp.os.vms newsgroup.  This means that postings to comp.os.vms get
automatically sent to INFO-VAX subscribers and messages sent to the INFO-VAX
list are automatically posted to comp.os.vms.  INFO-VAX can be a useful way
to participate in the newsgroup if you can't access the group directly
through a news reader.

An important point to keep in mind is that propagation delays vary, both
within the newsgroup and with INFO-VAX mailings.  It's possible that
postings may not be delivered for several days and some may appear out of

INTRO4.  How do I subscribe to or unsubscribe from INFO-VAX?

The address for subscription requests, as well as notes intended for the
moderator, is Info-VAX-Request@Mvb.Saic.Com.  Subscription requests are handled
automatically by a mail server.  This mail server ignores the subject line and
processes each line of the message as a command.  The syntax for subscribing
and unsubscribing and setting digest or non-digest modes is:
SUBSCRIBE INFO-VAX      (ADD is a valid synonym)
SET INFO-VAX DIGEST     (to receive in Digest format)
SET INFO-VAX NODIGEST   (to receive each message individually)
Case is irrelevant and attempts to fetch a copy of the mailing list will be
rejected (I consider the information to be confidential).  Any message not
understood by the mailserver will be forwarded to a human (allegedly) for
manual processing.

If you are on Bitnet, send a mail message containing the text 
"SUBSCRIBE INFO-VAX" to LISTSERV@(nearest listserv system).  To unsubscribe,
send a message containing the text "SIGNOFF INFO-VAX" to the *SAME* listserv

If you are on the Internet in the UK, send a message containing the

INTRO5.  How do I submit a question or a response?  What is etiquette?

If you are using a news reader, post your question to comp.os.vms.  If you
want to submit through INFO-VAX, send the message to

Before posting, please use available local resources, such as the manuals,
HELP and this FAQ first.  Also make a point of reading the release notes for
the product you're using, generally placed in SYS$HELP.  Often you'll find
the answer, and will save time and effort for all concerned.  (And you won't 
"annoy the natives"...)

When posting, please consider the following suggestions:

    1.  Include a valid e-mail address in the text of your posting or
        in a "signature" appended to the end.  Reply-to addresses in
	headers often get garbled.

    2.  If you are submitting a question, please be as specific as you
        can.  Include relevant information such as processor type, product
	versions (OpenVMS and layered products that apply), error message(s),
        DCL command(s) used, and a short, reproducible example of problems.  
        Say what you've tried so far, so that effort isn't duplicated.  Keep 
        in mind that there's not yet a telepathy protocol for the Internet.
        (The more detailed your description, the better that people can help 
        you with your question.)

    3.  If responding to a posting, include in your reply only as much of
        the original posting as is necessary to establish context.  As
	a guideline, consider that if you've included more text than you've 
	added, you've possibly included too much.  Never include signatures 
	and other irrelevant material.

    4.  Be polite.  If the question isn't worded the way you think is
        correct or doesn't include the information you want, try to
	imagine what the problem might be if viewed from the poster's
	perspective.  Requests for additional information are often
	better sent through mail rather than posted to the newsgroup.

    5.  If you have a problem with Compaq (or any other vendor's) product,
        please use the appropriate support channel.  Don't assume that
	newsgroup postings will get read, will be responded to by the 
        appropriate developers, or will be later followed up on...

    6.  If you are posting from a web browser, news reader or if you are 
        posting via email sent to INFO-VAX, please turn off MIME, vcard, 
        attachments, and other mechanisms that assume anyone reading the 
        post has the corresponding capability -- use the text-only option 
        of your web browser, news reader, or mailer.  Usenet is traditionally
	a text-only medium, and many comp.os.vms participants will use tools 
	that have this support disabled, or that do not have this support.
	If the message uses MIME or attachments or such, the text of your 
	message will be buried in a large pile of gibberish, and some tools 
	will send multiple copies of the text within a single posting.

Before posting your question to the comp.os.vms newsgroup or sending your 
message to the INFO-VAX list, also please take the time to review available 
etiquette information, such as that included in the following documents:

This information will document the etiquette of newsgroups, as well as 
providing you with the knowledge the vast amount of newsgroup-related 
information that is readily available to you, and where to find it...


Rather, please report these problems directly to Compaq.  (Why?  So that 
Compaq has a change to resolve and distribute a fix before other customer 
sites can be affected.  Most folks in the newsgroups are honest and deserve 
to know about potential security problems, but a few folks can and will make 
nefarious use of this same information.  Other sites will hopefully return 
the favor, and not post information that will potentially compromise YOUR 
site and YOUR computer environment.

INTRO6.  What is Encompass (DECUS)?

Encompass, the Enterprise Computing Association, is a Compaq user group
consisting of information technology professionals interested in the
products, services, and technologies of Compaq Computer Corporation and
related vendors. Encompass reaches out to experts and engineers alike, and
brings them together to promote awareness of and provide solutions for the
real IT problems and challenges your business faces every day. The Encompass
mission is to help you and your organization be more successful by providing
an open, objective knowledge exchange network.

For more information on Encompass, please visit the Encompass web site:

                                        [Jim Becker]

Encompass is a descendent of the organization known as DECUS, the Digital 
Equipment Computer Users Society.

INTRO7.  What archives of comp.os.vms/INFO-VAX are available?

Everything posted since 1990 is archived and available at:

					[Arne VajhЬj]

INTRO8.  Who are the corporate contacts for OpenVMS business issues?

  The following folks are the Compaq corporate contacts for 
  OpenVMS business issues, listed in descending order from the 
  Comoaq Corporate President to the OpenVMS Vice President (VP).
    Michael Capellas     Compaq President and CEO

    Mike Winkler         VP, Global Business Units

    Howard Elias         VP, Business Critical Solution Group

    Rich Marcello        VP, High Performance Server Division

    Mark Gorham          VP, Open Systems Software Group

  These folks will obviously respond best to cogently-worded OpenVMS
  corporate-level business issues.  These folks are NOT appropriate 
  contacts for any OpenVMS technical support issues nor for any OpenVMS
  technical support requests, nor for any other non-corporate-related, 
  non-business-related issues.  (For technical issues, please contact 
  the local Compaq Customer Support Center or your Compaq Reseller.)

VMS1.   What is OpenVMS?  What is its history?

OpenVMS, originally called VMS (Virtual Memory System), was first conceived in
1976 as a new operating system for the then-new, 32-bit, virtual memory line
of computers, eventually named VAX (Virtual Address eXtension).  The first VAX
model, the 11/780, was code-named "Star", hence the code name for the VMS
operating system, "Starlet", a name that remains to this day the name for the
system library files (STARLET.OLB, etc.).  VMS version X0.5 was the first
released to customers, in support of the hardware beta test of the VAX-11/780,
in 1977.  VAX/VMS Version V1.0 shipped in 1978, along with the first
revenue-ship 11/780s.

OpenVMS was designed entirely within Compaq (Digital Equipment Corporation).
The principal designers were Dave Cutler and Dick Hustvedt, with a wide
variety of other contributors.  OpenVMS was conceived as a 32-bit, virtual 
memory successor to the RSX-11M operating system for the PDP-11.  Many of 
the original designers and programmers of OpenVMS had worked previously on 
RSX-11M, and many concepts from RSX-11M were carried over to OpenVMS.

OpenVMS VAX is a 32-bit, multitasking, multiprocessing virtual memory 
operating system. Current implementations run on VAX systems from Compaq
and other vendors.

OpenVMS Alpha is a 64-bit multitasking, multiprocessing virtual memory 
operating system. Current implementations run on Alpha systems from
Compaq, and other vendors.

Work to port OpenVMS to systems based on the Intel IA-64 architecture 
(specifically to the Itanium Processor Family) is presently underway.

				[Paul Winalski]
				[Arne VajhЬj]

For more details on OpenVMS and its features, read the OpenVMS Software
Product Description at:
  OpenVMS typically uses SPD 25.01.xx and/or SPD 41.87.xx.

Additional information on the general features of various OpenVMS
releases, release dates, as well as the development project code
names of specific releases, is available at:

Additional historical information -- as well as pictures and a variety of 
other trivia -- is available in the VAX 20th anniversary book:

For information on the FreeVMS project (also see the related software
licensing topics VMS9, ALPHA4), see:

VMS2.   What is the difference between VMS and OpenVMS?

VMS and OpenVMS are two names for the same operating system.  Originally,
the operating system was called VAX-11/VMS; it changed to VAX/VMS at
around VAX/VMS V2.0.  When the VMS operating system was ported to the
Alpha platform, it was renamed OpenVMS, for both VAX and Alpha (and
for the Itanium Processor Family), in part to signify the high degree 
of support for industry standards such as POSIX, which provides many 
features of UNIX systems. 

For those versions with POSIX, an OpenVMS license allows you to install 
and run POSIX for OpenVMS at no additional charge; all you need is the 
media and documentation which can be found on the Consolidated Distribution 
and On-Line Documentation CD-ROMs.  Support for the POSIX package on more
recent OpenVMS releases is not available, various parts of POSIX such as
calls from the API are being integrated more directly into OpenVMS.  For 
more information on POSIX for VMS see question SOFT2

What became confusing is that the OpenVMS name was introduced first
for OpenVMS AXP V1.0 causing the widespread misimpression that OpenVMS
was for Alpha AXP only, while "regular VMS" was for VAX.  In fact, the
official name of the VAX operating system was changed as of V5.5, though 
the name did not start to be actually used in the product until V6.0.

The proper names for OpenVMS on the two platforms are now "OpenVMS VAX"
and "OpenVMS Alpha", the latter having superseded "OpenVMS AXP".

				[Arne VajhЬj]

VMS3.   How do I port from VMS to OpenVMS?

You already did.  Wasn't that easy?  (See question VMS2.)

VMS4.   Which is better - OpenVMS or UNIX?

This question comes up periodically, usually asked by new subscribers who are
long-time UNIX users. Sometimes, it is ignored totally; other times, it leads
to a long series of repetitive messages that convince no one and usually carry
little if any new information.  Please do everyone a favor and avoid
re-starting this perpetual, fruitless debate.

Seriously, OpenVMS and the better implementations of UNIX are all fine
operating systems, each with its strengths and weaknesses.  If you're
in a position where you need to choose, select the one that best fits
your own requirements, considering, for example, whether or not the
layered products or specific OS features you want are available.

					[Steve Lionel]

VMS5.   Is Compaq continuing funding and support for OpenVMS?


Active development of new OpenVMS releases is underway, as well
as the continuation of support.

Please see the following URLs for details, roadmaps, and related

[VMS6 removed, replaced by Y2K section]

VMS7.   What OpenVMS CD-ROM products are available?

Various distributions are available.

For information on the available part numbers and current products
(OpenVMS distribution kits, media, documentation, etc) and associated 
licensing information, please see the OpenVMS Software Product Description 
(SPD), available at:
  OpenVMS typically uses SPD 25.01.xx and/or SPD 41.87.xx.

The following CD-ROMs contain just the OpenVMS Alpha operating system.
These are bootable, and can be used to run BACKUP from CD-ROM.

  QA-MT1AP-H8   OpenVMS Alpha V6.1-1H2 hardware release CD-ROM
  QA-MT1AG-H8   OpenVMS Alpha V6.2-1H3 hardware release CD-ROM
  QA-MT1AD-H8   OpenVMS Alpha V7.1-1H1 hardware release CD-ROM
  QA-MT1AR-H8   OpenVMS Alpha V7.1-2 maintenance release CD-ROM
  QA-MT1AT-H8   OpenVMS Alpha V7.2-1 maintenance release CD-ROM
  QA-MT1AU-H8   OpenVMS Alpha V7.2-1H1 hardware release CD-ROM

The following are the consolidated ECO distribution kit subscriptions, and
these provide sites with eight updates of the current ECO kits per year:

  QT-3CQAA-C8   OpenVMS Alpha

OpenVMS VAX and OpenVMS Alpha source listings CD-ROM sets include the
source listings of most of OpenVMS, and these CD-ROM sets are invaluable 
for any folks working directly with OpenVMS internals, as well as folks
interested in seeing examples of various programming interfaces.

  QB-MT1AB-E8   OpenVMS Alpha Source Listings CD-ROM
  QT-MT1AB-Q8   OpenVMS Alpha Source Listings CD-ROM Updates
  QB-001AB-E8   OpenVMS VAX Source Listings CD-ROM
  QT-001AB-Q8   OpenVMS VAX Source Listings CD-ROM Updates
VMS8.   In what language is OpenVMS written?

OpenVMS is written in a wide variety of languages.

In no particular order, OpenVMS components are implemented using Bliss, 
Macro, Ada, PLI, VAX and DEC C, Fortran, UIL, VAX and Alpha SDL, Pascal, 
MDL, DEC C++, DCL, Message, and Document.  And this is certainly not a 
complete list. However, the rumor is NOT true that an attempt was made 
to write pieces of OpenVMS in every supported language so that the 
Run-Time Libraries could not be unbundled.  (APL, BASIC, COBOL and RPG 
are just some of the languages NOT represented!)

There are a large variety of small and not-so-small tools and DCL command
procedures that are used as part of the OpenVMS build, and a source code 
control system capable of maintaining over a hundred thousand source files 
across multiple parallel development projects, and overlapping releases.

VMS9.   How do I obtain or transfer a VMS license?

If you are a DECUS member and are considering acquiring and using a VAX 
or Alpha system for hobbyist (non-commercial) use, (free) licenses for 
OpenVMS VAX and OpenVMS Alpha are available to DECUS members.  In 
addition to the license, VAX and Alpha distribution CD-ROM kits are 
available with OpenVMS, DECwindows Motif, DECnet and TCP/IP networking, 
compilers, and a variety of layered products.

For further information, link to:

On the hobbyist license registration form (as of August 2001), you are
offered the choice of the "OpenVMS VAX" license(s), the "OpenVMS Alpha"
license(s), and the "Layered Products" licenses.  You will want the
operating system license for your particular OpenVMS platform AND you 
will want the "Layered Products" licenses.

For information on licenses for educational customers, see the Compaq
CSLG license program and the OpenVMS Educational license program:

To transfer a commercial OpenVMS license from one owner to another,
or to purchase a commercial license, you can contact Compaq Computer
Corporation at 1-800-DIGITAL (in North America), or your local or
regional sales office.

Commercial developers can join the CSA program, and can (potentially)
receive discounts on various software product licenses and software
distributions, as well as on hardware purchases.  Please see ALPHA4.

					[Stephen Hoffman]
                                        [Scott Snadow]

VMS10.  What is OpenVMS doing about the Euro currency symbol?

For information on the current status and plans for support of the
European Monetary Union's Euro currency symbol in OpenVMS, see:

VMS11.  Why hasn't OpenVMS been ported to Intel (IA32) systems?

Why?  Business reasons...

Because there is a belief that there would be no market to justify
the effort and the expense involved in porting OpenVMS to systems
using the Intel IA32 architecture.  (Each maintainer of a product
or package for OpenVMS would have to justify the port to "OpenVMS
IA32", akin to a port from OpenVMS VAX to OpenVMS Alpha.  The effort
involved in porting OpenVMS from VAX to Alpha was huge.)

Because every one of the core applications would have to be ported
from Alpha to IA32, and then customer and third-party applications
would also have to be ported.

Because there are design features that required by OpenVMS that are
not available on IA32, features that would require redesigning OpenVMS
to operate in the environment, making ports rather more difficult.
ASTs and interlocked operators are obvious prerequirements.

Because Alpha is faster than Intel IA32 systems -- if OpenVMS is to
be ported, a port to a slower system is more difficult to sell.

Because Intel is expecting to replace IA32 processors with IA64.

Because hobbyists have been easily able to acquire OpenVMS systems
and the DECUS hobbyist OpenVMS licenses.

Because OpenVMS already operates on Compaq and third-party Alpha
systems; specific features in support of third-party vendor-customized
bootstrap capabilities for use on third-party systems are present in
OpenVMS Alpha V7.1-2 and later releases.

Because there are assumptions that some of the stability of OpenVMS
arises from the stability of the underlying VAX and Alpha hardware, 
and systems based on components such as ISA and random memory SIMMs
might not be as stable.

But yes, it would be nice to have.

                                           [Stephen Hoffman]

VMS12.  Are there any general-access OpenVMS systems available?


  o Hobbes

      Hobbes is a MicroVAX 3100 Model 40 for which free access 
      and accounts are available to OpenVMS enthusiasts. This 
      system has BASIC, Pascal, Fortran, and C compilers installed.
      If you would like an account on Hobbes, please see the FAQ at:

      This system is strictly for non-commercial use.

                                     [Scott Squires, Steven Shamlian]

  o OpenVMS Galaxy Test Drive

      Compaq currently offers an OpenVMS Galaxy Test Drive system,
      based on an AlphaServer 4100 series configured as two instances 
      of the OpenVMS operating system.  For details, please see:

  o Compaq CSA Test Drive:
VMS13.  What version of OpenVMS do I need?

For information on supported platforms, please see the
OpenVMS Software Product Description (SPD) for the
particular OpenVMS version of interest.
  OpenVMS typically uses SPD 25.01.xx and/or SPD 41.87.xx.

For a table of OpenVMS versions for various platforms,
please see:

For information on the Multia, related Alpha single-board 
computers, or other officially unsupported systems, please
see ALPHA8 and ALPHA13.

The following is a rule-of-thumb for Alpha platform support.
The table contains the earliest OpenVMS Alpha release with 
support for a particular series of Alpha microprocessors:

Microprocessor | OpenVMS   | General
  Generation   | Version   | Comments

  21064  EV4   : V1.0      : few systems; most EV4 req later; upg avail
  21164  EV5   : V6.2      : subsequent upg available
  21164A EV56  : V6.2-1H3  : subsequent upg to V7.1 and later
  21264  EV6   : V7.1-2    : subsequent upg typically to V7.2-1 or later
  21264A EV67  : V7.1-2    : subsequent upg typically to V7.2-1 or later
  xxxxxx EV68  : V7.2-1    : believed/probable; currently expectation

VMS14.  How can I submit OpenVMS Freeware?

  For the guidelines and submission info, please visit the URL:

  To order a Freeware CD-ROM kit, request part number QA-6KZAA-H8.

VMS15.  Porting applications to OpenVMS?

Porting can range from simple to rather complex, and depends on the
features used on the original platform.

This section covers generic porting, and porting from OpenVMS VAX
to OpenVMS Alpha.  (Porting from OpenVMS VAX to OpenVMS Alpha is
often quite simple and involves little more than rebuilding from
source, though a few applications using features specific to VAX will 
require some additional effort to port.)

Several manuals on porting from OpenVMS VAX to OpenVMS Alpha are 
available in the OpenVMS documentation set, including information 
on porting VAX Macro32 assembler code to the Macro32 compiler on 
OpenVMS Alpha, on management differences, on upgrading privileged 
code, and application migration:

Details on the C programming environment are available at:

Details on porting VAX C to Compaq C are are available at:

An OpenVMS Porting Library is available at:

Information on the Enterprise Toolkit, a Visual-based development
environment for developing applications for OpenVMS using a Microsoft
platform, is available at:

Details on DCE, CORBA, BridgeWorks, and COM/DCOM middleware is available at:

Information on the COE standards is available at:

A wide variety of programming development tools and middleware are 
available as commercial products (eg: DECset, IBM MQseries), and 
various tools are also available as shareware or Freeware.  Please 
see other sections of this FAQ, and please see:
VMS16.  How do I join Compaq Solutions Alliance?

The Compaq Solutions Alliance (CSA) is a (free) program that is open to
and that supports software partners, consultants, and service providers:

CSA provides members with discounts on hardware, porting assistance, and
many other benefits.

For those familiar with the program, the DIGITAL Association of Software
and Application Parterns (ASAP) program has been incorporated into CSA.

The Compaq Solutions Alliance Technical Journal (CTJ) is "web-published"
monthly, and available at:

VMS17.  memory management, resource management, process scheduling, etc?

  So you have been instructed to write a school research paper on OpenVMS,
  and you need technical content on the OpenVMS Virtual Memory System, on
  any memory segmentation, on OpenVMS Resource Management, on the OpenVMS
  File System, on the OpenVMS user interface, etc.

  Invariably, your professor/instructor/teacher will ask you a series
  of questions.  Most commonly, the questions will request descriptions
  of one or more of the following items, and at varying levels of detail:

    o process scheduling algorithm(s)

    o Interprocess comunications

    o Process or system synchronization constructs

    o Memory management and/or virtual memory implementation

    o RMS or XQP file structures

    o Resource management

    o History of Compaq OpenVMS

    o History of Compaq and/or of Digital Equipment Corporation (DEC)

  Any particular presentation or research paper, and particularly a scholastic
  presentation, can have many different potential target audiences, and very
  different presentation levels.  Further, the usual underlying reason for
  scholastic presentations and scholastic research projects really has little
  to do with the subject matter, it is a task specifically intended to teach
  the student(s) (eg: you) how to perform the research.  The instructor already
  knows most of (all of?) the information that you have been asked to collect.

  For low-level (more technical) details on OpenVMS, the book you want is the
  Internals and Data Structures Manual (IDSM), available in your school or
  computing center library, and the IDSM can also be purchased.  Additional
  low-level details of the Alpha microprocessor are available in the Alpha
  Architecture Reference Manual documentation that is available for download.
  (A pointer to the Alpha technical documentation is elsewhere in the FAQ.)

  For higher-level (less technical) details, the OpenVMS documentation set
  is available on-line.   The Programming Concepts and the File Systems manual
  are probably the best manuals to start with, depending on the particular
  level of detail the research requires.

  And please understand the hesitation of various folks to provide you with
  a completely-written research report on your topic.  Why?  We might have
  to work with you after you graduate -- you need to know how to perform
  at least basic research on your own, regardless of the topic.  

DOC1.   Where can I find online copies of OpenVMS manuals?

The Compaq OpenVMS and layered product documentation is copyrighted 

HTML format on-line product documentation sets for specific Compaq 
OpenVMS products are presently available at:

Documentation is offered on separately orderable CD-ROM media through 
a subscription to the Consolidated On-Line Documentation (ConOLD) product 
(see VMS7.)  ConOLD manuals are readable with BNU, a viewer that is supplied 
with the documentation distribution.  BNU can display HTML, Bookreader, and
documentation in other formats.  

MGBOOK, a viewer for Bookreader-format documentation is available for
character-cell terminals (eg. VTxxx) via the WKU VMS Freeware file server
-- see question SOFT1 for details.
					[Steve Lionel]
					[Stephen Hoffman]

DOC2.   What online information is available?

On your OpenVMS system, the HELP command can provide a wealth of information,
not only on DCL commands but on system services (HELP System_Services) and
Run-Time Library routines (HELP RTL_Routines).  The introduction displayed
when you type the HELP command with no additional keywords provides further

OpenVMS Marketing runs a WWW server at
(  Here, you will find product information, 
strategy documents, the contents of the latest OpenVMS Freeware CD-ROM and 
much more.

Software Product Descriptions (SPDs) for most every OpenVMS-related product 
Compaq sells is available via:

System performance data (see ALPHA5), product infosheets, release notes and 
much more are also available.

In addition,

provides a handy method to search all of Compaq's public web servers for
information of any kind.

Compaq's Customer Services organization also hosts an Internet server. 
Various contract-access and non-contract access ECO (patch) kits are
available, see section MGMT25.

The Compaq Systems and Options Catalog (SOC) archive is available at:

The Systems and Options Catalog has been replaced by Compaq QuickSpecs:

The Compaq DSNlink electronic product support network (a good source for 
reporting problems, obtaining patches and ECOs, scanning Compaq support 
databases, searching for example programs, etc) is available at:

Compaq's Business Link provides product information, prices and permits 
online ordering:

The services provided by BusinessLink are being replaced by other and
country-specific mechanisms, please see the above URL for details.

Information on Compaq hardware, software, products and services is 
available through various telephone numbers:

    1-800-AT-COMPAQ     : voice : Compaq (including DIGITAL and Tandem)
                                  products and services
    1-800-DIGITAL	: voice : DIGITAL products and services
    1-800-DEC-2717	: voice : The DECchip Hotline
    1-508-568-6868	: voice : (alternate number for above)
    1-800-STORWORK      : voice : The Compaq StorageWorks team

David Mathog offers two HTML documents which contain useful information
about OpenVMS.

The VAXarchive (hardware and software information) is at:

Useful OpenVMS information and an extensive set of links is available at:

A wide variety of Compaq VAX, Alpha, platform and other product 
documentation (some introductory, some technical) is available at:

The Compaq inFORM magazine and OpenVMS Times newsletters have email
subscriptions available, see:

Also see the DFWCUG Longwords newsletter:

Back issues of the old Digital Technical Journals (DTJs) are at:


An OpenVMS Programming FAQ is available at:

                                       [Martin VorlДnder]

A Customer VAX to Alpha upgrade diary:


Scanned versions of old DIGITAL hardware manuals are available at:

DOC3.   What books and publications are available?

A bibliography of current and recent OpenVMS books is available at:

The Butterworth-Heinemann Digital Press imprint offers a number of 
OpenVMS books.  A website is available at:

Information on specific OpenVMS books is also available at:

Also see DOC10.

DOC4.   How do I extract the contents of a HELP topic to a text file?

To extract all the text of a HELP topic (and its subtopics) to a text file
for perusal with a text editor, printing out, etc., use the following

     $ HELP/OUT=filename.txt help-topic [help-subtopic]

If the help text you want is not in the standard help library (for
example, it's help for a utility such as MAIL that has its own help
library), add /LIBRARY=libname after the HELP verb.  To see the names
of help library files, do a directory of SYS$HELP:*.HLB.

DOC5.   Does OpenVMS Marketing have an e-mail address?

Yes - if you can't get the answers to questions elsewhere, if you have
comments or complaints about OpenVMS, send mail to
(This address is NOT a support channel, and is solely intended to provide
informal method to communicate directly with members of OpenVMS Marketing.)

DOC6.   What OpenVMS-related WWW sites are available?    (Sponsored by OpenVMS Marketing)          (Sponsored by DECUS - DFWLUG)      (Sponsored by Arne VajhЬj)             (Sponsored by Saiga Systems)	      (Sponsored by Wayne Sewell)  (Sponsored by proGIS Software)      (Sponsored by Jeff Cameron)

The following web site is sponsored by "The Beave", and provides 
information that is directly relevent to system managers, security 
managers, and others interested in ensuring the continued security 
of OpenVMS systems:

Suggestions (indirectly) provided by the above include disabling the 
port 11 and 15 stats provided by IP packages such as Multinet.

DOC7.   removed.  See MGMT25.

DOC8.   Where can I find info about undocumented OpenVMS features?

After all this discussion about undocumented VMS features I started a
collection of some documentation :-)) about them on

Also see the following:
                                                [Arne VajhЬj]

Various examples of undocumented features are also available on the
OpenVMS Freeware:

DOC9.   Where is documentation on the DECnet Phase IV protocols?

Documentation and Specifications for DECnet Phase IV can be found at:

DOC10.  Where can I learn about how the VMS executive works internally?

The OpenVMS Internals and Data Structure manual (IDSM) explains how the 
OpenVMS executive works. The book covers the operating system kernel: 
process management; memory management; the I/O subsystem; and the 
mechanisms that transfer control to, from, and among these. It gives an 
overview of a particular area of the system, followed by descriptions of 
the data structures related to that area and details of the code that 
implements the area.

The first edition of the OpenVMS Alpha internals book describes Version 
1.5.  Although there have been several releases of  OpenVMS Alpha since 
Version 1.5 (V6.1, V6.2, V7.0, V7.1, etc) and many details in the book 
are no longer accurate, it continues to provide a strong conceptual 
description of OpenVMS internals. 

This book has been split into five pieces, each to be updated separately.
The first such volume, published in early 1997, was "OpenVMS Alpha Internals 
and Data Structures: Scheduling and Process Control," which covers the 
Version 7.0 implementation of true multithreading and the changed scheduling 
model it implies.

The internals books are available through Digital Press, an imprint of
Butterworth-Heinemann. You can order by phone (from US and Canada, 
1-800-366-2655, or from elsewhere, 781-904-2500). You can also fax an 
order to 1-800-446-6520 or 781-933-6333. The order form and additional 
information are available on their web site .

ISBN           Title

1 55558 156 0  OpenVMS Alpha Internals: Scheduling and Process Control
1 55558 120 X  OpenVMS AXP Internals and Data Structures: Version 1.5
1 55558 059 9  VAX/VMS Internals and Data Structures: Version 5.2

					[Ruth Goldenberg]

DOC11.  Where can new users find tutorial information about OpenVMS?

First, see if your local site has information on this topic.  Each site can have
site-specific features and configuration.  Some sites will have site-specific
new user's documentation, covering various site-specific things that are
difficult or impossible for the general OpenVMS documentation to cover.

Various introductory manuals are available in the OpenVMS documentation set,
including the OpenVMS User's Guide.  The OpenVMS manuals -- including the 
OpenVMS User's Guide -- are available at:

Some of the OpenVMS books available from the Butterworth-Heinemann 
Digital Press imprint ( include:

       Introduction to OpenVMS, 5th Edition,
       Lesley Ogilvie Rice
       ISBN 1 55558 194 3

       The OpenVMS User's Guide, Second Edition
       Patrick Holmay
       ISBN 1 55558 203 6

       Introduction to OpenVMS
       David W Bynon
       ISBN 1 878956 61 2

       OpenVMS System Management Guide
       Richard Berry
       ISBN 1 55558 143 9

       Using DECwindows Motif for OpenVMS
       Margie Sherlock
       ISBN 1 55558 114 5

       Writing Real Programs in DCL, Second Edition
       Hoffman and Anagnostopoulos
       ISBN 1 55558 191 9

  For various features OpenVMS books, please see:

  Various user-maintained websites are also available, including a
  beginner's FAQ, various user-written FAQs, a bibliography of books
  on OpenVMS, and information on various other hardware and software

  Members of the DECUS DFWLUG maintain a website with many materials
  available, including an Overview of OpenVMS, an Introduction to DCL
  and the TPU Editor, Advanced DCL Command Procedures, OpenVMS
  Operations: Batch, Print, Tape, an Introduction to OpenVMS Management,
  to OpenVMS User Management, to OpenVMS Network Management, and to
  OpenVMS Cluster Management.  These training materials have been
  presented at various DECUS symposia, and can be downloaded from:

  Compaq offers training information and Technical Resource Kits
  (TRKs) and other Training for OpenVMS at:

  An OpenVMS certification (testing) program is also available.

  The following URL has an OpenVMS Quiz:

  CCSS Interactive Learning has OpenVMS training materials available:

  AcerSoft Training information:

  MindIQ training information:

DOC12.  Access to the OpenVMS Netscape Navigator documentation?

  The documentation URLs embedded into the browser itself may
  not operate correctly in all cases, and (for reasons not
  worthy of repeating here) redirects may not be available.

  You can manually access the documentation via:

DOC13.  What OpenVMS mailing lists are available?


  OpenVMS Freeware archive announcement list
  Two-way echo of vmsnet.internals:
  OpenVMS Alpha Internals discussions: (*)
  BLISS discussions (*)
  Process Software MultiNet mailing list (news gateway):
  Process Software TCPware mailing list (news gateway):
  Process Software PMDF mailing list (news gateway):                 PMDF mailing list (news gateway)
  Discussion list for SRI's CHARON-VAX VAX emulator package:
  Info-Zip's Zip & UnZip discussion list:

  To subscribe to any of the lists, the command SUBSCRIBE should be sent in
  the body of a mail message to the -request address like so:


  For example:

  (*) The Alpha-IDS and BLISSters lists have been dormant for some time, but 
  they do still exist.

                                      [Hunter Goatley]

  RADIUS-VMS, a RADIUS server for OpenVMS discussion forum:
        Send subscription requests to (MadGoat MX-List processor):

  Forum for Internet Service Providers (ISPs) running OpenVMS:
        Send subscription requests to (MadGoat MX-List processor):

                                      [Ruslan R. Laishev]

  An Info-WASD mailing list for users of Mark Daniel's WASD web server
  for OpenVMS VAX and Alpha exists.  Information about this list server 
  and details on how to subscribe to the list can be found at:

                                      [Jeremy Begg]

DOC14.   What is this Ask The Wizard website I've heard about?

The Compaq OpenVMS Ask The Wizard (ATW) website is available at:

A zip archive of questions and answers can be downloaded at:

TIME1.   A brief history of OpenVMS Timekeeping, please?

  Why does OpenVMS regards November 17, 1858 as the beginning
  of time...

  The modified Julian date adopted by the Smithsonian Astrophysical 
  Observatory (SAO) for satellite tracking is Julian Day 2400000.5, 
  which turns out to be midnight on November 17, 1858.

  SAO started tracking satellites with an 8K (nonvirtual) 36-bit
  IBM 704 in 1957 when Sputnik went into orbit. The Julian day 
  was 2435839 on January 1, 1957. This is 11225377 octal, which 
  was too big to fit into an 18-bit field. With only 8K of memory, 
  the 14 bits left over by keeping the Julian date in its own 36-bit 
  word would have been wasted.  SAO also needed the fraction of the 
  current day (for which 18 bits gave enough accuracy), so it was 
  decided to keep the number of days in the left 18 bits and the 
  fraction of a day in the right 18 bits of one word.

  Eighteen bits allows the truncated Julian day (the SAO day) to 
  grow as large as 262143, which from November 17, 1858, allowed 
  for 7 centuries. Possibly, the date could only grow as large as 
  131071 (using 17 bits), but this still covers 3 centuries and 
  leaves the possibility of representing negative time.  The 1858 
  date preceded the oldest star catalogue in use at SAO, which also 
  avoided having to use negative time in any of the satellite tracking 

  The original Julian Day (JD) is used by astronomers and expressed 
  in days since noon January 1, 4713 B.C.  This measure of time was 
  introduced by Joseph Scaliger in the 16th century.  It is named in 
  honor of his father, Julius Caesar Scaliger (note that this Julian 
  Day is different from the Julian calendar that is named for the 
  Roman Emperor Julius Caesar!).

  Why 4713 BC?  Scaliger traced three time cycles and found that they 
  were all in the first year of their cyle in 4713 B.C.  The three 
  cycles are 15, 19, and 28 years long.  By multiplying these three 
  numbers (15 * 19 * 28 = 7980), he was able to represent any date 
  from 4713 B.C. through 3267 A.D.

  The starting year was before any historical event known to him.  In
  fact, the Jewish calendar marks the start of the world as 3761 B.C.
  Today his numbering scheme is still used by astronomers to avoid the 
  difficulties of converting the months of different calendars in use 
  during different eras.

  The following web sites:

  are all good time-related resources, some general and some specific
  to OpenVMS.

					[Stephen Hoffman, Dale Dellutri]

TIME2.   How does OpenVMS VAX maintain system time?

  VAX systems maintain an interval clock, and a hardware clock.

  The VAX hardware clock is called the TOY ("Time Of Year") clock.  The 
  register associated with the clock is called the TODR ("Time Of Day 

  The TOY clock -- as used -- stores time relative to January first of the
  current year, starting at at 00:00:00.00.  It is a 100 Hz, 32-bit counter,
  incremented every 10ms, and thus has a capacity of circa 497 days.

  OpenVMS (on the VAX platform) stores system date information -- and in
  particular, the current year -- in the system image, SYS$SYSTEM:SYS.EXE.
  The TOY is used, in conjunction with the base date that is stored and
  retrieved from the system image, to initialize the interval clock value 
  that is stored in EXE$GQ_SYSTIME.

  Once the interval clock is loaded, the system does not typically reference 
  the TOY again, unless a SET TIME (with no parameters) is issued.  The 
  interval clock value is updated by a periodic IPL22 or IPL24 (depending 
  on the specific implementation) interrupt.  (When these interrupts are 
  blocked as a result of the activity of higher-IPL code -- such as 
  extensive driver interrupt activity or a hardware error or a correctable
  (soft) memory error -- the clock will "loose" time, and the time value 
  reported to the user with appear to have slowed down.)

  On most (all?) VAX systems, the battery that is associated with the TOY 
  clock can be disconnected and replaced if (when) it fails -- TOY clock 
  problems in VAX systems do regularly get tracked back to a failed nicad 
  or lithium battery pack.
					[Stephen Hoffman]

TIME3.   Why does my system time drift?

  Memory errors, hardware problems, or most anything operating at or
  above IPL 22 or IPL 24 (clock IPL is system family dependent; code
  executing at or above the clock IPL will block the processing of
  clock interrupts), can cause the loss of system time.  Clock drift 
  can also be caused by normal (thermal) clock variations and even by
  the expected level of clock drift.

  When clock interrupts are blocked as a result of the activity of 
  high-IPL code -- such as extensive driver interrupt activity or a 
  hardware error or a correctable (soft) memory error -- the clock 
  will "loose" time, and the time value reported to the user with 
  appear to have slowed down.  Correctable memory errors can be a
  common cause of system time loss, in other words.

  Clock drift can also be (deliberately) caused by the activity of the 
  DTSS or NTP packages.

  Also see ALPHA17, VAX8, and TIME8.

TIME4.   Managing Timezones, Timekeeping, UTC, and Daylight Savings?

  You will want to use the command procedure:


  to configure the OpenVMS Timezone Differential Factor (TDF) on OpenVMS 
  V6.0 and later.  Select the BOTH option.  This configures the OpenVMS 
  TDF settings, though it may or may not configure the TDF and the 
  timezone rules needed or used by other software packages.  

  Please do NOT directly invoke the following command procedures:

    SYS$MANAGER:UTC$CONFIGURE_TDF.COM   ! do not directly use
    SYS$MANAGER:UTC$TIMEZONE_SETUP.COM  ! do not directly use

  TCP/IP Services V5.0 and later use the OpenVMS TDF, UTC, and timezone
  support.  Earlier versions use a TDF mechanism and timezone database
  that is internal to the TCP/IP Services package.  Also on the earlier
  versions, the TDF must be manually configured within TCP/IP Services,
  in addition to the OpenVMS configuration of the TDF.

  DECnet-Plus in V7.3 and later uses the OpenVMS TDF, UTC, and timezone
  support, and displays its timezone prompts using UTC$TIME_SETUP.COM.
  Earlier versions use a TDF TDF mechanism, timezone database, and 
  automatic switch-over that is internal to the DECnet-Plus package.
  Also on earlier versions, the TDF must be configured within the
  DECnet-Plus DECdtss package, in addition to the OpenVMS configuration
  of the TDF.

  Application code using Compaq C (formerly DEC C) will use the OpenVMS
  UTC and TDF mechanisms when the C code is compiled on OpenVMS V7.0 and
  later (and when the macro _VMS_V6_SOURCE is NOT defined).  Compaq C does
  NOT use the OpenVMS UTC and TDF mechanisms when the C code is compiled
  on OpenVMS releases prior to V7.0, or when the preprocessor declaration
  _VMS_V6_SOURCE is declared.

  DCE DTSS TDF details TDB.

  In OpenVMS Alpha V6.1, V6.2, and V6.2-1Hx, the TDF value is written
  to SYS$BASE_IMAGE.EXE.  With OpenVMS Alpha V7.0 and later and with
  OpenVMS VAX V6.0 and later, SYS$SYSTEM:SYS$TIMEZONE.DAT contains the
  TDF.  This means that OpenVMS Alpha systems will need to have the TDF
  value reset manually on reboots prior to V7.0.  

  During OpenVMS Bootstrap, the SYSINIT module reads SYS$TIMEZONE.DAT to 
  acquire the TDF for use in the system global cell EXE$GQ_TDF.  This is 
  done to ensure that the system boots with a valid TDF (a value which 
  may be zero). The UTC system services get the TDF from this cell. These 
  services, as well as the Compaq C RTL, must have a valid TDF.  (Prior to 
  OpenVMS V7.3, if either DECnet-Plus or DECnet/VAX Extensions is configured 
  and run, the image DTSS$SET_TIMEZONE.EXE is invoked and can override the 
  TDF and timezone rule settings from SYSINIT or from UTC$TIME_SETUP.COM -- 
  this image runs even if DTSS is disabled.  If the settings do not match
  (due to inconsistencies in timezone specification in UTC$TIME_SETUP.COM 
  and NET$CONFIGURE.COM), DTSS will reset the values to match its 

  Prior to OpenVMS V7.3, daylight savings time switchover is handled
  automatically only when DCE DTSS or DECnet-Plus DTSS is in use.  In
  V7.3, OpenVMS can be configured to automatically switch over to
  daylight savings time, and also generates an event that interested
  applications can use to detect the switch-over between standard time
  and daylight time.

  The manual switchover between daylight savings time and standard time
  is correctly accomplished via the SYS$EXAMPLES:DAYLIGHT_SAVINGS.COM
  command procedure procedure.

  If you switch the TDF or daylight savings time setting, you will also
  want to restart or reconfigure any time-sensitive applications (those 
  not using the time differential factor (TDF) change event available in 
  V7.3 and later).  Examples of these applications include the need to 
  restart the NFS client and (yes) NTP. (NTP will want to try to "drift" 
  the time (see TIME6), and will find the daylight savings time switch-over 
  to be far too large to "drift". Hence the NTP restart.)  You can also use 
  the (undocumented) TCP/IP Services (prior to V5.0) commands:

    SET TIME/DIFF=[positive or negative TDF integer]

  to reset the value of the logical name UCX$TDF.

  Prior to V7.3, the command:


  can be used to modify the settings of the SYS$TIMEZONE_DAYLIGHT_SAVING, 
  based on the SYS$TIMEZONE_RULE.

  The following are other TDF-related logical names used/available on
  OpenVMS systems, with typical Daylight Savings and Standard Settings 
  for the US Eastern Time (ET) timezone.



        'f$integer(f$element(0," ",f$logical("notes$timezone"))/-100)'

  For information on ZIC and related tools used to manage the OpenVMS 
  Timezone database, please see the DEC C Run-time Library Utilities 
  Reference Manual -- though the title would imply otherwise, this 
  particular manual is part of the OpenVMS documentation set, and not 
  part of the Compaq C (formerly DEC C) documentation set.

TIME5.   How to troubleshoot TDF problems on OpenVMS?

  This is an OpenVMS Alpha system prior to V7.0 and the startup is not
  invoking the procedure:


  This is an OpenVMS system prior to V6.0, where there is no OpenVMS
  TDF nor UTC available.

  The version of the application does not use the OpenVMS TDF.  This
  includes TCP/IP Services prior to V5.0, applications using Compaq C 
  built on or targeting OpenVMS prior to V7.0, and systems using the
  DECnet-Plus DTSS mechanisms prior to the release associated with 
  OpenVMS V7.3.  (DCE TDF TBD.)

  If you should find either of the following two timezone-related database 
  files located in SYS$SPECIFIC:[SYSEXE]:


  These two files are in an erroneous location and must be recreated in 
  the correct directory:


  If the DCL command:


  shows these files in SYS$SPECIFIC:[SYSEXE], then delete them and use 
  SYS$MANAGER:UTC$TIME_SETUP.COM to recreate them.

  On OpenVMS versions prior to V7.3, if the file:


  is present on your system, then you may need to invoke:


  to recreate the timezone files correctly.  Invoke this command
  immediately after [re]executing SYS$MANAGER:UTC$TIME_SETUP.COM.)

  system, then you may need to execute the following commands:


TIME6.   How can I keep the OpenVMS system time synchronized?

  To help keep more accurate system time or to keep your system clocks
  synchronized, TCP/IP Services NTP, DECnet-Plus DECdtss, DCE DTSS, and
  other techniques are commonly used.  If you do not have IP access to
  a time-base, then you could use dial-up access to NIST or other
  authoritative site.

  There exists code around that processes the digital (ie: binary) 
  format time that is available via a modem call into the NIST clock
  (the Automated Computer Telephone Service (ACTS)), and code that 
  grabs the time off a GPS receiver digital link, or a receiver 
  (effectively a radio and a codec) that processes the time signals 
  from radio station WWV, WWVH, WWVB, or similar.  (Processing these 
  time protocols often involves little more than reading from an
  EIA232 (RS232) serial line from the receiver, something that is 
  possible from most any language as well as directly from DCL.)

  One example of acquring a time-base involves the IRIG time format
  (IRIG-A, -B, -G), a binary signal containing the current time in 
  hours, minutes, seconds and days since the start of the current year.
  IRIG can also contain the time of day as the number of seconds since 
  midnight.  Compaq Custom Systems and third-party vendors offer various 
  IRIG-based reader/generator modules for OpenVMS systems.

  Differing time servers (DECnet-Plus DTSS, DCE DTSS, NTP, etc) do not 
  coexist particularly well, particularly if you try to use all these 
  together on the same node.  Please pick and use just one.  (If needed,
  you can sometimes configure one package to acquire its timebase from 
  another protocol, but one and only one time server package should have 
  direct control over the management of and drifting of the local OpenVMS 
  system time.)

  Useful URLs:

TIME7.   How can I configure TCP/IP Services NTP as a time provider?

  An NTP time provider provides its idea of the current time to NTP
  clients via the NTP protocol.  Most systems are NTP clients, but...

  NTP has a heirarchy of layers, called strata.  The further away from
  the actual NTP time source (Internet time servers are at stratum 1), 
  the lower the strata (and the larger the number assigned the statum).

  NTP explicity configured at stratum one provides time to NTP operating
  at lower strata, and the provided time is acquired based on the local
  system time or via some locally-accessable external time source.

  NTP at other (lower) strata both receive time from higher strata and can
  provide time to lower strata, and automatically adjust the local stratum.
  The highest stratum is one, and the lowest available stratum is fifteen.

  The TCP/IP Services NTP package can operate at any stratum, and can be
  configured as a peer, as a client, or as a broadcast server.

  With TCP/IP Services V5.0 and later, the only supported reference clock
  is the LCL (local system clock).  If your system has an excellent clock
  or if the system time is being controlled by some other time service
  (such as DTSS or GPS), you can configure NTP to use the system clock as
  its reference source.  This will mimic the master-clock functionality,
  and will configre NTP as a stratum 1 time server.  To do this, enter
  the following commands in TCPIP$NTP.CONF:

    server prefer
    fudge stratum 0

  For local-master functionality, the commands are very similiar.  Use:

    fudge stratum 8

  The difference between these two is the stratum, and the omission of
  the prefer keyword.  Specifying a higher stratum allows the node to
  act as a backup NTP server, or potentially as the sole time server on
  an isolated network.  The server will become active only when all other
  normal synchronization sources are unavailable.  The use of "prefer"
  causes NTP to always use the specified clock as the time synchronization

  With the TCP/IP Services versions prior to V5.0, the NTP management is 
  rather more primitive.  To configure the local OpenVMS system from an
  NTP client to an NTP server (on TCP/IP Services versions prior to V5.0), 
  add the following line to the sys$specific:[ucx$ntp]ucx$ntp.conf file:

    master-clock 1

  Also, for TCP/IP Services prior to V5.0, see the NTP template file:


  For current TCP/IP Services documentation, please see:

TIME8.   How can I drift the OpenVMS system time?

  With DECdts and TCP/IP Services NTP, the system time value is "drifted" 
  (rather than changed), to avoid the obvious problems that would arise 
  with "negative time changes".  The same basic clock drifting technique 
  is used by most (all?) time servers operating on OpenVMS, typically using
  the support for this provided directly within OpenVMS.

  An example of the technique used (on OpenVMS VAX) to drift the system
  time is the SETCLOCK tool on the OpenVMS Freeware.

  For information on the use of the EXE$GL_TIMEADJUST and EXE$GL_TICKLENGTH 
  cells on OpenVMS Alpha, see _OpenVMS AXP Internal and Data Structures", 
  located on page 348.

TIME9.   Why does VAX need a SET TIME at least once a year?

  Because the VAX Time Of Year (TOY) has a resolution of 497 days, the VAX 
  system time is stored using both the TOY and the OpenVMS VAX system image 
  SYS.EXE.  Because of the use of the combination of the TOY and SYS.EXE, 
  you need to issue a SET TIME command (with no parameters) at least once 
  between January 1st and about April 11th of each year, and whenever you 
  change system images (due to booting another OpenVMS VAX system, booting 
  the standalone BACKUP image, an ECO that replaces SYS.EXE, etc).  

  The SET TIME command is automatically issued during various standard 
  OpenVMS procedures such as SHUTDOWN, and it can also obviously be issued 
  directly by a suitably privileged user.  Issuing the SET TIME command 
  resets the value stored in the TOY, and (if necessary) also updates the 
  portion of the time (the current year) saved in the SYS.EXE system image.

  This VAX TOY limit is the reason why OpenVMS VAX installation kits and
  standalone BACKUP explicitly prompt for the time during bootstrap, and 
  why the time value can "get weird" if the system crashes outside the 
  497 day window (if no SET TIME was issued to update the saved values), 
  and why the time value can "get weird" if a different SYS$SYSTEM:SYS.EXE 
  is used (alternate system disk, standalone BACKUP, etc).

TIME10.   Why can't I do a SET TIME command?  Help managing DTSS?

If you try to set the system time with the SET TIME command, and see
one of the following messages:

%SET-E-NOTSET, error modifying time
-SYSTEM-F-IVSSRQ, invalid system service request

%SET-E-NOTSET, error modifying time
-SYSTEM-E-TIMENOTSET, time service enabled; enter a time service command to
update the time

A: This occurs if the time on the local system is controlled by a time service
software, for example the distributed time service software (DTSS) provided as
part of the DECnet/OSI installation. The DTSS software communicates with one or
more time servers to obtain the current time. It entirely controls the local
system time (for DECnet/OSI, there is a process named DTSS$CLERK for this);
therefore, the usage of the SET TIME command (and the underlying $SETTIM system
service) is disabled.

The first message is displayed on systems running DECnet/OSI V6.1 and earlier.
On systems with newer DECnet/OSI (DECnet-Plus) software, the second (and more
informative) message is given.

You shouldn't have to change the time manually - you should be doing this
through the time server - but if you insist...  you'll have to shutdown DTSS:


This will shutdown DTSS$CLERK. You may then change the system time as usual.
To restart the DTSS software, type


ALTPRI) and must be granted the NET$MANAGE identifer to shutdown and
restart DTSS.

If you wish to "permanently" disable DTSS on a system running DECnet-Plus, the
above NCL sequence must be performed each time the system is bootstrapped.

If DTSS is running and no time servers are configured, you can (and will) see
the following messages at regular intervals:

%%%%%%%%%%%  OPCOM   2-SEP-1999 19:41:20.29  %%%%%%%%%%%
Message from user SYSTEM on UNHEDI
Event: Too Few Servers Detected from: Node LOCAL:.mynode DTSS,
        at: 1999-09-02-19:41:20.296-04:00Iinf
        Number Detected=0,
        Number Required=1
        eventUid   5FA70F4F-616E-11D3-A80E-08002BBEDB0F
        entityUid  DE9E97DE-6135-11D3-8004-AA000400BD1B
        streamUid  D6513A46-6135-11D3-8003-AA000400BD1B

You can either configure the appropriate number of time servers, or you can
disable DTSS, or you can ignore it and (if OPCOM is set to write to the
log via via the logical names in SYLOGICALS.COM/SYLOGICALS.TEMPLATE) clean
out OPERATOR.LOG regularly.

You can also simply disable the display of these messages:

$ mcr ncl block event dispatcher outbound stream local_stream global filter -
    ((Node, DTSS), Too Few Servers Detected)

                                                  [Wayne Sewell]

If you wish to disable the automatic TDF adjustment for daylight savings
time (on OpenVMS versions prior to V7.3), you can use the command:

  ncl> set dtss automatic TDF change = false

or alternatively, you can set the local timezone to one that does not 
include the automatic daylight savings time change-over.

TIME11.   Details of the OpenVMS system time-keeping?

  VAX hardware time-keeping details...

  TOY clock
  This is battery backed up hardware timing circuitry used to keep the 
  correct time of year during rebooting, power failures, and system 
  shutdown.  This clock only keeps track of months, days, and time.
  The time is kept relative to January 1st, at 00:00:00.00 of the year 
  the clock was initiailized.

  This is the OpenVMS VAX system time cell.  This cell contains the number 
  of 100ns intervals since a known reference.  This cell is incremented by 
  100000 every 10ms by an hardware interval timer.

  This cell contains the time and date the system time was last adjusted 
  by EXE$SETTIME.  It uses the same format as EXE$GQ_SYSTIME.  On adjustment 
  of the system time a copy of EXE$GQ_SYSTIME is stored in this cell in both 
  memory and on disk.  This cell is used to get the year for the system time.

  This cell contains the time and date the system time was last adjusted by
  EXE$SETTIME. It uses the same format as the time of year clock. On adjustment
  of the system time this cell gets saved back to both memory and disk.  The
  contents of this cell are used to test the validity of the TOY clock.

  The system parameters SETTIME and TIMEPROMPTWAIT determine how the system 
  time will be set.

  THEN the contents of the TOY clock are compared to those of EXE$GL_TODR.

        IF the TOY clock is more than a day behind EXE$GL_TODR
        THEN the TOY clock is presumed invalid.

        IF the TOY clock is within a day of EXE$GL_TODR
        THEN the system time is calculated as follows:


  IF SETTIME = 1 or the TOY clock is invalid
  THEN the value of TIMEPROMPTWAIT determines how to reset the time of year.

        THEN the user is prompted for the time and date, for a length of time
        equal to TIMEPROMPTWAIT microfortnights.

        THEN the time of year is the value of EXE$GL_TODR + 10ms.

        IF TIMEPROMPTWAIT < 0to proceed
        until they do so.

        THEN the user is prompted for the time and date and unable 

  When booting a CD-ROM containing an OpenVMS VAX system, the system will 
  typically be deliberately configured prompt the user to input the time 
  -- this is necessary in order to boot with the correct time.  

  If either TIMEPROMPTWAIT or SETTIME are set to zero, OpenVMS VAX will 
  use the TOY clock to get the time of year, and the year will be fetched 
  from the CD-ROM.  The value of the year on the CD-ROM media (saved in 
  the SYS.EXE image) will most likely be that of when the CD-ROM was made, 
  and cannot be changed.  Unless the current year happens to be the same 
  year as that on the CD-ROM, most likely the year will be off.  (Further, 
  with the calculation of Leap Year also being dependent on the current 
  year, there is a possibility that the date could be off too.)

  Alpha hardware time-keeping details...

  Battery-Backed Watch (BB_WATCH) Chip
  This is battery backed up hardware timing circuitry used to keep the 
  correct time of year during rebooting, power failures, and system 
  shutdown.  This clock keeps track of date and time in 24 hour binary 

  This is the OpenVMS Alpha system time cell.  This cell contains the number 
  of 100ns intervals since November 17, 1858 00:00:00.00.  This cell is 
  incremented by 100000 every 10ms by an hardware interval timer.

  This cell is used by OpenVMS Alpha to keep track of the last time and date 
  that EXE$GQ_SYSTIME was adjusted.  It keeps the same time format as 
  EXE$GQ_SYSTIME.  The value in this cell gets updated in memory and on 
  disk, every time EXE$GQ_SYSTIME gets adjusted.

  - The system parameters SETTIME and TIMEPROMPTWAIT determine how the 
    system time will be set.

  - If SETTIME = 0 then EXE$INIT_HWCLOCK reads the hardware clock to set 
    the system time.

          THEN the value of TIMEPROMPTWAIT determines how long the user is
          prompted to enter the time and date.  If time expires and no time 
          has been entered the system acts as if TIMEPROMPTWAIT = 0.

          THEN the system time is calculated from the contents of
          EXE$GQ_SAVED_HWCLOCK + 1.

          THEN the user is prompted for the time and date and unable to
          continue until the information is entered.

  Unlike the VAX, the Alpha hardware clock tracks the full date and time, 
  not just the time of year.  This means it is possible to boot from the
  CD-ROM media without entering the time at the CD-ROM bootstrap.  (This
  provided that the time and date have been initialized, of course.)

  IA-64 (Itanium) hardware time-keeping details to be added...

TIME12.  UTC vs GMT vs vs UT1/UT1/UT2 TDF?  What are these acronyms?

  The results of an international compromise -- though some would say 
  an international attempt to increase confusion -- UTC is refered to 
  as "Coordinated Universal Time" (though not as CUT) in English and as 
  "Temps Universel CoordinnИ" (though not as TUC) in French.

  Universal Time UT0 is solar time, UT1 is solar time corrected for a 
  wobble in the Earth's orbit, and UT2 is UT1 corrected for seasonal 
  rotational variations in rotation due to the Earth's solar orbit.

  GMT -- Greenwich Mean Time -- is UT1.  GMT is the time at the (old)
  Royal Greenwich Observatory (in Greenwich), not to be confused with
  the Royal Greenwich Observatory located at Herstmonceux Castle in 
  Sussex, England.

  UTC is based on an average across multiple atomic clocks, and is kept 
  within 0.9 seconds of GMT, through the insertion (or removal) of seconds.
  In other words, UTC matches GMT plus or minus up to 0.9 seconds, but
  UTC is not GMT.

  TDF is the Timezone Differential Factor, the interval of time between
  the local time and UTC.  Areas that celebrate daylight savings time
  (DST) will see periodic changes to the TDF value, when the switch-over
  between daylight savings time and standard time occurs.  The switch-over
  itself is entirely left to local governmental folks, and can and has
  varied by political entity and politics, and the switch-over has varied
  over the years even at the same location.  

  If your local OpenVMS system time is off by one hour (or whatever the
  local DST change) for some or all applications, you probably need to 
  reset your local TDF.

  Further discussions of history and politics, the Royal Observers' 
  outbuildings, and the compromise that left the English with the Time 
  Standard (the Prime Meridian) and the French with the standards for 
  Distance and Weight (the Metric System) are left to other sources.  
  Some of these sources:

TIME13.  Customizing your TDF (Timezone) Setting?

  Individual, local, and regional differences on the use (or the lack of 
  use) of Daylight Savings Time (DST) are quite common.

  If you need to add (or remove) daylight savings time for your area or
  otherwise alter the rules for your local area, you will probably end 
  up creating a variation to an existing timezone rule.

  The necessary zone line to add for WhereEverLand will probably look 
  something like this:

# Zone  NAME            GMTOFF  RULES/SAVE      FORMAT  [UNTIL]
Zone    WhereEver       2:00    -               WhereEver

  The OpenVMS source file for the timezone rules here:


  You'll then want to ZIC this to create your own timezone definiton.

  ZIC is documented in the OpenVMS Documentation Set, in the Compaq C 
  Run-Time Library Reference Manual.  (Despite the name of the manual, 
  it is part of the OpenVMS documentation set and not the C manuals.)

  Once you have created the new rule, use SYS$MANAGER:UTC$TIME_SETUP.COM
  to select the new timezone -- with V7.3 and later, this tool will
  notice the new timezone and will offer it, on earlier releases, you
  may/will have to hack the tool somewhat.  (Don't even think of trying
  to define the TZ or other time-related logical names directly yourself.)

  For various timezone rules, see the tar.gz files (these are gzipped tar 
  archives) available at:

[End of Part 1/5]

 --------------------------- pure personal opinion ---------------------------
   Hoff (Stephen) Hoffman   OpenVMS Engineering

Inferno Solutions
Hosting by

Закладки на сайте
Проследить за страницей
Created 1996-2021 by Maxim Chirkov
Добавить, Поддержать, Вебмастеру