OpenVMS Demos: Programmer's Corner
(promoting OpenVMS through example programming)

This entire sub-domain is a private effort of free information.
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Note: my OpenVMS Resource Area has moved here

OpenVMS Application Demos

Click here to view a directory of my free demo programs which include:

"HP-BASIC for OpenVMS Alpha"

(a.k.a. "Compaq-BASIC for OpenVMS Alpha", "DEC-BASIC")
(should work with no modifications on VAX)

System Password Notes:

1. OpenVMS really is "open" because I wrote the afore mentioned program in a about an hour using two OpenVMS system calls (sys$getjpi and sys$hash_password) which are publicly documented here. You need to have system privileges in order to access someone else's hashed password, but nothing could prevent an unscrupulous system manager (or support staff) from using this technique to acquire someone else's password in order to commit a crime using that person's account. This is a big no-no in the world of Sarbanes-Oxley (SOX)
    
2. My busy little AlphaServer-4100 (EV5/300MHz) averages 1 million guesses in 273 seconds. Since there are 38^6 "six character passwords", a worst case run would require 3,010,936,384 guesses. Divide this number by 1M and you get 3010.9 which then is multiplied by 273 then divided by 3600 to yield 228 hours or 9.5 days. Multiply this figure by 38 for every character added to the six character password, so a seven character password would require 361 days while an eight character password would require 37.5 years thus forcing criminals to look for another method.
    
3. as a result of this experiment, I've decided to set the minimum password length to 8 on all of my OpenVMS systems via the following command in authorize:

    $set def sys$system
    $run authorize
    uaf>mod * /pwdminimum=8
    exit
    $

   which results in the total number of possible candidate minimum length passwords to be guessed changing from 38^6 (3.01e+9) to 38^8 (4.34e+12). Of course you could always use a larger password and I think I'll do this on my priv accounts. BTW, it might be a good idea to monitor unusual access to SYSUAF using ACL's and $SET AUDIT
    

4. currently any password you enter is UPCASED before being tested and/or stored. Starting with OpenVMS-7.3-2 an authorize flag named "PWDMIX" to enable case-sensitive and extended-character passwords.
    
5. password cracking can be sped up considerably by copying the SYSUAF to a PC (you still need OpenVMS system privs to do this) and running a standalone tool. Check out this link for more details (p.s. tools like this are one more reason to enforce longer passwords and enable the "case-sensitive password feature" which will be available with  OpenVMS-7.3-2)

"HP-BASIC for OpenVMS VAX"

(a.k.a. "Compaq-BASIC for OpenVMS VAX", "Compaq-BASIC for VAX", "VAX-BASIC")

• download a demo which calls a MACRO-32 function to PEEK at memory (can be converted to POKE but I can't think why you'd want to do this)

"HP-CXX for OpenVMS Alpha"

(a.k.a. "Compaq-CXX for OpenVMS Alpha", "Compaq-C++", "HP-C++")

• download a C++ application to convert SEGY formatted data to ASCII (then you will be able to pull the data into a spread sheet). Note that SEGY is an acronym for "Society of Exploration Geophysicists" Y-format. This name of this program is SEGY2ASC

"HP-C for OpenVMS Alpha", "HP-C for OpenVMS VAX"

(a.k.a. "Compaq-C for OpenVMS Alpha", "Compaq-C for OpenVMS VAX", "DEC-C")

Note: VAX-C was phased out prior to VMS 6.0 and replaced with DEC-C. Don't do any new program development with VAX-C.

DCL (Digital Control Language a.k.a. DEC Control Language)

• download a demo to Create/Open/Read/Close a text file (then calling $MAIL as we go)
• download info about "BACKUP Anomaly #1 (exclude list bug)" under  OpenVMS-7.2 (note: OpenVMS Engineering has fixed this with a free patch that's available from their web site)
• view into about "BACKUP Anomaly #2 (alias directories not copied)" under  OpenVMS-7.2 for VAX
  (p.s. please don't send me any suggestions on the use of /ALIAS or /NOALIAS. I've already tried all permutations and believe that this switch is only meant to be used when backing up a system disk to tape so that directories are not backed up more than once).
• download a DCL program to fix "FTP induced SAVESET corruption". Click here for technical info.
• download a DCL program which demos a way to quickly delete many files
• download three DCL scripts ("MMAIL.COM" for Multinet by David Mathog and two TCPware variations by me) which will allow you to get around a problem when sending MIME attachments from OpenVMS MAIL.
  Notes:
  • This script is no longer required with Multinet v5.1 which was released April-2007
  • This script is no longer required with TCPware 5.8 which was release April-2008
  • Forget about sending MIME-based email from DCL. Instead, check the demos above to send SMTP mail or VMS mail directly from within your application.
• download a DCL program ("ENV_CHECK.COM") to check environmental temperatures, fan speeds and power supplies on Alpha platforms. Uses undocumented DCL lexicals like: f$getsyi("thermal_vector") f$getsyi("fan_vector") f$getsyi("power_vector") f$getsyi("thermal_vector")
  Note: non-priv users aren't able to execute the DCL Lexical SYS$GETSYI
  Click here http://www.parsec.com/openvms/undocumented.php for more undocumented OpenVMS features.
• download a DCL program ("ENV_CHECK_101.COM") to check environmental temperatures, fan speeds and power supplies on Alpha platforms. This program is a tweaked version of ("ENV_CHECK.COM") for use with your the LOGIN.COM scripts of your privileged users. Uses undocumented DCL lexicals like: f$getsyi("thermal_vector") f$getsyi("fan_vector") f$getsyi("power_vector") f$getsyi("thermal_vector")
  Note: non-priv users aren't able to execute the DCL Lexical SYS$GETSYI
  Click here http://www.parsec.com/openvms/undocumented.php for more undocumented OpenVMS features.

M32 (a.k.a. "Macro for OpenVMS VAX", "Macro-32")

• download a little utility to reset hardware error counters in OpenVMS (unless we reboot, this is all we have until OpenVMS-7.3-2)

M64 (a.k.a. "Macro for OpenVMS Alpha", "Macro-64")

• learn about HP's MACRO64 freeware (for Alpha) including the required free license to activate it.
  Note: OpenVMS Engineering people have told me that HP-C has replaced MACRO-64 as the preferred way to generate Alpha binaries.

Notes for "Demo Programs" from this site

1. Source Environment:
   1. All OpenVMS BASIC demos should work on either VAX or Alpha with no modifications (except the macro-32 based example which will only work on VAX because it contains VAX instructions). I have not had the opportunity to try these demos on Itanium but I am sure they will work.
   2. Prior to Y2K, this source code was edited on OpenVMS using $EDIT/EDT on a VT-420 character-cell terminal with the WIDTH set to 132 column mode and TABS set every 8 columns (eg. 1, 9, 17, 25, etc.).
   3. Since Y2K, this source code was edited on OpenVMS using $EDIT/EDT on a Windows 2000/XP/Vista PC using Reflection for UNIX and OpenVMS from Attachmate (formerly WRQ). This product uses an ANSI font which exactly matches the properties of a DEC character cell terminal.
2. Platform Environment:
   1. Many external functions (like WCSM_TRNLNM) were written on VAX with the intention of squeezing every last bit of performance out of my systems (in my case they were all under powered and over loaded; I remember a bunch of little VAX-11/730 machines with 20 interactive users logged in all day long). Once you move from VAX to Alpha or Itanium, it might make more sense to simply call LIB$GET_LOGICAL
3. Zip Environment:
   1. all files have been zipped on OpenVMS using "ZIP 2.1" from the "Info-Zip archive" found on HP's OpenVMS Freeware CD. Any UNZIP program should work including WinZip.
4. Viewing These Files on Windows:
   1. Source code can't be viewed at all with Notepad
   2. For best results, rename the file extension to ".txt" then open with Internet Explorer (since non of these files have a DOCTYPE, they will all be rendered in quirks mode with no wrapping). If desired, you could still copy-n-paste from IE to WordPad.
   3. When viewed from WordPad or Word, you'll need a non-proportional font (try "COURIER NEW 10") with tabs set at a multiple of 0.67 inches (switching from inches to cm may provide finer resolution). The programs may only "look correct" when viewed from OpenVMS using a VT100 (or higher) character-cell terminal or any Windows applications which correctly supports spaces and tabs like the VT emulator found in Attachmate's Reflection for UNIX and OpenVMS.
   4. Some files may not open correctly on Windows (like "something.com" which is a DCL text file on OpenVMS but a binary command file on Windows) so you may need to rename them to "something.txt"
5. FTPing from Windows back to OpenVMS
   1. If you're working in a locked down environment and aren't allowed to unzip on OpenVMS, you may find it necessary to unzip on Windows then FTP the desired file to OpenVMS. Please remember to always FTP text files in ASCII mode. FTP'ing text files in Binary mode will result in "fixed length 512 byte" records when you really want "variable length" records.
   2. While I'm at it, just let me say that FTP ASCII mode was developed to translate the <EOL> (end-of-line) rules from the files on the sending system to the end-of-line rules required by the files on the receiving system. Some operating systems use <CR>, some use <LF><CR>, some use <CR><LF>, at least one uses <Control-Z>. Text files created with EDT in OpenVMS store data as a series of string descriptors so you'll never (usually) find any embedded <EOL> control characters.
   3. Be aware that some FTP clients can change transfer modes (when set to auto) based upon the file extension. This can cause a problem when sending/receiving OpenVMS DCL scripts which are text files with a ".COM" extension because this file extension is also used for some Windows and DOS files which are binary.

Other Notable Applications

Intercepting OpenVMS Mail Delivery (using DELIVER)

• I'm amazed by the number of OpenVMS people who are not aware of the DELIVER freeware program which allows you to intercept "OpenVMS Mail Delivery" (including mail from TCP/IP sources) and then do cool things like run user-written programs and/or batch jobs to automatically process the message.
• The distribution includes Pascal source code and binaries for both VAX and Alpha.
• It can be found on the V4 Freeware CD-ROM shipped with OpenVMS or can be downloaded free of charge here at the HP website or here at Process Software's OpenVMS resource area
• OpenVMS Notes: DELIVER (the email interception utility)

Intercepting OpenVMS Mail Delivery (using PMDF)

• If you don't want to use unsupported freeware to intercept your email, then checkout PMDF from Process Software which can also do many other cool things like MIME DECODE etc.
• Binaries are also available for UNIX and Windows-NT (including Windows-2000). I can only assume that Process Software will be producing an Itanium version after they port TCPware.
• if you trial this software, be sure you execute DCL command $PMDF CONFIG before you begin testing

My 2 cents worth about "HP-BASIC for OpenVMS Alpha"

1. Native (builtin) support for RMS-based files including sequential, relative and indexed.
   Yes, you can develop non-SQL compliant databases.
    
2. Like Pascal, run-time errors can (if desired) be handled locally with WHEN ERROR blocks rather than using a common handler like "ON ERROR GOTO". But you can use both methods if you desire.
    
3. Enforced variable declaration can be achieved with the directive "OPTION TYPE=EXPLICIT"
    
4. SELECT CASE statements seem much more readable than compound "IF THEN" - "ELSE" - "END IF"
    
5. Line numbers are not required (unless you reference the BASIC function "ELN")
    
6. interpreter mode is only available on VAX

1. Compile mode only; no interpreter (I do not consider this a problem)
    
2. The Alpha compiler does much better code optimization than VAX so if you weren't really careful while creating code for VAX just recompiling for Alpha will provide you with compile-time speed improvements. For example, the following two programs (example 2a and 2b) generate different object code on VAX but generate the same optimized object code on Alpha even when complied with optimization=level=0 (none).

                             ! example 2a (written by a careless VAX programmer).
   1000 a% = 3               ! the VAX complier produces CISC code to convert 3 from real to integer at runtime
        b% = 4               ! the VAX complier produces CISC code to convert 4 from real to integer at runtime
        print a% + b%        !
        end program 1        ! return -s- to DCL
   
                             ! example 2b (written by a careful VAX programmer).
   1000 a% = 3%              ! both compilers generate code which represents an integer 3
        b% = 4%              ! both compilers generate code which represents an integer 4
        print a% + b%        !
        end program 1        ! return -s- to DCL

3. However, running the Alpha compiler with optimization=level=4 (full) would yield the following equivalent program:

                             ! example 3 (why add the variables if you don't have to?)
   1000 print "7"            ! the compiler added 3 to 4 "at compile time" so only this I/O statement was required
        end program 1        ! return -s- to DCL

4. Here's another example program which yields radically different object files on VAX compared to Alpha.

   1000 option type=explicit ! example 4
        declare long i%      !
        for i% = 1 to 100    ! should be "1% to 100%" on VAX; Alpha doesn't care because long was declared
            print i%         !
        next i%              !
        end program 1        !

   If you compile with optimization=level=4 and used a smaller loop, the Alpha complier might decide to just generate a series of PRINT statements. This is called "loop unrolling".
    

5. So-called "DEC languages" targeted at Alpha and Itanium are based upon the "GEM Optimizing Compiler System". GEM is a project code-name rather than an acronym. Everything coming out of DEC in those days had names like GEM, Emerald, Opal, etc.
   A Few GEM links:
   1. http://www.hpl.hp.com/hpjournal/dtj/vol4num4/vol4num4art8.pdf
   2. http://source.rfc822.org/pub/mirror/ftp3.ds.pg.gda.pl/people/macro/DEC/DTJ/DTJ808/DTJ808PF.PDF
   3. http://h71000.www7.hp.com/openvms/journal/v5/portingmacrocompiler.html

Links:

• my OpenVMS resource page
• my OpenVMS Mini-FAQ page
• my "VAX to Alpha" Porting Diary page

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Neil Rieck
Kitchener - Waterloo - Cambridge, Ontario, Canada.