HP OpenVMS Systems Documentation

GNV

This document describes the features and functionality provided with the OpenVMS GNV software. It explains how to install, set up, and use the software on your OpenVMS system.

Revision/Update Information: This is a new document.

Operating System: OpenVMS Alpha V8.3
OpenVMS I64 V8.3

Software Version: OpenVMS Alpha GNV V2.1-2, OpenVMS I64 GNV V2.1-2

Hewlett-Packard Development Company, L.P.
Cupertino, California

© Copyright 2008 Hewlett-Packard Development Company, L.P.

The information contained herein is subject to change without notice. The only warranties for HP products and services are set forth in the express warranty statements accompanying such products and services. Nothing herein should be construed as constituting an additional warranty. HP shall not be liable for technical or editorial errors or omissions contained herein.

Linux® is a U.S. registered trademark of Linus Torvalds.

UNIX® is a registered trademark of The Open Group.

© Copyright 1989, 1991 Free Software Foundation, Inc.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

This document includes information about the GNV software, including:

• Features and functionality
• Utilities provided with the software
• Installation and setup instructions
• Differences between the OpenVMS GNV utilities and their counterparts on UNIX® systems
• Reporting problems
• Documentation provided with the GNV software
• Sources of information on the Internet

Conventions Used in This Document

OpenVMS utilities, commands, file names, and directory names are shown in uppercase text, while UNIX utilities, commands, file names, and directory names are shown in lowercase text. If you are reading this documentation in an output format other than text (.TXT) --- such as in PostScript or HTML output --- UNIX utilities, commands, file names, and directory names are shown in monospace text.

The following additional conventions are used in this document.

Reader's Comments

HP welcomes your comments on this manual. Please send comments to either of the following addresses:

The main change in V2.1-2 is removal of several installation problems.

• Installation --- Changed default to omitting automatic creation of mount points for all disks.
• Installation --- Configuration files created at installation time include the architecture name in the file name to avoid conflicts in heterogeneous clusters.

The main change in V2.1 is support of the symlink capability that has been added to RMS in OpenVMS. Other minor bugs have been fixed as well.

• Installation --- Improved stability in setting up the default mount points for existing disk devices.
• ln -s --- Now makes an actual symbolic link in the RMS file creates.
  This is enabled by new features in RMS on OpenVMS V8.3.
• mnt --- Has improved record-keeping for reporting the mount points.
• bash --- Command recall now generally works, at least if the terminal width is 80.
• cc --- Improvements in the cc wrapper.

Several new UNIX utilities have been added in GNV V1.6.

• du --- Displays disk usage, including the size of directories in the current or specified directory. The utility recursively displays the sizes of all subdirectories. The size listed for a directory denotes the total size of all files within that directory.

  Note On an OpenVMS system, the size displayed by du represents only the highest generation of each of the files in the directory.

  
  By showing all directories in a directory tree, du allows a user to easily assess how disk space is being used.
  For more information, type:

  bash$ du --help

  
  or

  bash$ man du

• printenv --- Displays an environment variable. If no argument is present, displays all environment variables.
  For more information, type:

  bash$ printenv --help

  
  or

  bash$ man printenv

• env --- Runs a program in a modified environment.
  As with the printenv command, specifying the env command with no argument will display the set of environment variables. More importantly, you may specify one or more environment variables, and run a program with those variables set. The values of those variables stay in effect only for the duration of that program.
  For more information, type:

  bash$ env --help

  
  or

  bash$ man env

• which --- Displays the location (path) of the specified utility. When you type a command to bash that is not a bash "internal" command, BASH searches for the executable for the command in the default path (environmment variable PATH). The which utility indicates where in the path the executable for that command is found.
  For more information, type:

  bash$ which --help

  
  or

  bash$ man which

• GNU tar ( gnutar ) --- Most UNIX systems include a tar utility. Many Linux® systems ship GNU tar . Traditionally, GNV has included VMSTAR, which is a tar look-alike written for OpenVMS. Because GNU tar has more capabilities than VMSTAR, it has been ported to OpenVMS for use with GNV.
  GNU tar is especially useful for reading OpenSoure tarballs, which are often shipped compressed as GZIP files. Using VMSTAR, the tarball must be decompressed prior to reading with tar . For very large tarballs, this process can be time-consuming. GNU tar allows you to read tarballs compressed with either gzip or bzip2 in-line. That is, you need not decompress them in a separate command.
  For example:

  bash$ gnutar -xzf gnutar.tar.gz

  
  The current GNV kit includes both the new GNU tar image and the older VMSTAR. In this kit, the tar command still invokes VMSTAR. To run the new GNU tar , type gnutar as shown in the preceding example.

  Caveats HP recommends using tar (either tar (VMSTAR) or gnutar (GNU tar )) for reading OpenSource tarballs. You can also use tar to save files on your OpenVMS system to a tarball. However, this works well only for UNIX-style files. The tar utility works especially well for stream_LF files, either copied from UNIX or GNU systems, or created by UNIX programs with C Run-Time Library functions. The tar utility does not work well on some other OpenVMS file types. It can successfully copy variable-length text files; however, it corrupts other types of variable-length files. tar corrupts object files generated by compilers. When a variable-length text file is written to a tarball and then restored to a directory on OpenVMS, the result is a stream_LF file with the same text contents as the original. This might not be suitable for some applications. Be very careful when using tar to back up non-stream_LF files. This warning applies especially to GNU tar , but can also apply to VMSTAR.

  Note about Image Names In this release of GNV, the new GNU tar utility is invoked by typing gnutar in the command line. Typing tar in the command line invokes VMSTAR. For more information, type: bash$ gnutar --help or bash$ man gnutar

• g++ added to GNV wrapper
  The wrapper utility processes UNIX-style compile and link (and related) commands. It reads commands such as the UNIX cc command and invokes the appropriate OpenVMS DCL command.
  For this release, g++ has been added as a synonym for cxx . This matches the gcc command to invoke the C++ compiler.

The GNV software provides an open source, GNU-based, UNIX environment for OpenVMS. It provides UNIX application developers, system managers, and users a UNIX-style environment so that they can easily develop and port UNIX software to OpenVMS. (GNU is a UNIX-like operating system that is free software. Linux is basically a GNU system: the system is GNU, while the kernel is Linux.)

GNV provides a UNIX-like shell (command-line interpreter) environment and a C Run-Time Library (CRTL) supplemental library to provide utilities typically found on UNIX systems. The shell used by GNV is bash (Bourne-Again SHell, from GNU, using the POSIX.2 specification).

http://www.opensource.org/licenses/gpl-license.html

GNU:[SRC.GNV.FINDUTILS]COPYING.

/gnu/src/gnv/findutils/copying.

It has come to our attention that some users like to run GNV utilities from the DCL prompt rather than from within bash . While this may work in many cases, HP does not support this method and does not guarantee that the utilities will work as expected. Most noticeably effected will be use of wildcards, which must be processed by bash . They will not work when a GNV utility is run from DCL. The following example illustrates the inconsistency of results obtained when running ls from the DCL prompt:

$ ls
A        PRINT_ENV.C  T.C     TEST.H     TEST_FWRITE.C  test
HELLO.C  SLEEP.C      TEST.C  TEST.H-GZ  t.t.t.t.t

$ ls *.c
/VMS$COMMON/GNV/bin/LS.EXE: *.c: no such file or directory

$ ls *.C
/VMS$COMMON/GNV/bin/LS.EXE: *.c: no such file or directory
$

ODS-5 disks allow use of files with extended file names, including most UNIX style filenames. Such file names are common in Open Source software. GNV includes mostly ported Open Source (or free software) code, and as such contains numerous files with UNIX style file names.

While it may be possible to install GNV (or at least portions of GNV) on ODS-2 disks, HP recommends that you install GNV on an ODS-5 disk. Installing GNV on an ODS-2 disk is likely to result in numerous installation warning and error messages. GNV has been tested primarily on an ODS-5 disk. HP does not guarantee the functionality of GNV on an ODS-2 disk.

Likewise, you can operate GNV on an ODS-2 disk, but some file naming features will not be usable on such a disk. You will not be able to make use of case-senstive file names or file names with special characters, such as multiple dots, which are so common in UNIX environments.

5 Utilities Provided with GNV

This section lists the UNIX utilities provided with GNV and describes any differences observed between the utilities as used on OpenVMS systems and the counterparts as used on UNIX systems.

5.1 UNIX Utilities Provided for OpenVMS

Table 1 lists the utilities provided with GNV on OpenVMS. Included for some of the listed utilities are OpenVMS command equivalents as well as behaviors that vary from expected behavior on a UNIX system. HP does not guarantee that all variances have been observed and documented.

The following GNV utilities have been observed to exhibit behavior that varies from their UNIX counterparts.

• tar (this runs the OpenVMS utility VMSTAR, which differs slightly from the the genuine UNIX tar utility. Try gnutar instead.)
• vi (this runs a vi emulator based on the OpenVMS utility TPU, which differs slightly from the genuine UNIX vi utility)
• The intent of GNV is that all utilities accept UNIX-style file specifications (that is, those specifications containing slashes "/", single or double dots ".", "..", and so forth.) Several utilities included with GNV were ported to OpenVMS previously and can accept OpenVMS-style file specifications. In fact, some may not accept UNIX-style file specifications, such as the following:
  • unzip

This section provides directions for installing GNV onto your OpenVMS system. The latest GNV software is included in [GNV.KIT] on the Open Source Tools CD-ROM. You can also downline load the GNV software from either of the following locations:

http://h71000.www7.hp.com/OPENSOURCE/opensource.html

or

http://gnv.sourceforge.net.

To install the GNV software on your system disk, follow these steps:

1. Load the installation kit media onto an available drive.
2. Log in to the SYSTEM account (at the login prompt, enter user name SYSTEM and the appropriate password), or an account with equivalent privileges.
3. At the DCL prompt ($), type the following command, as shown, where device-name is the name of the device containing the kit (a CD-ROM drive).

   $ PRODUCT INSTALL GNV /SOURCE=device-name:[GNV.KIT]

   
   To install your GNV software on a location other than the system disk, see Section 6.2.
   
4. When you enter the PRODUCT INSTALL command, the system responds with a display similar to the following:

   The following product has been selected: DEC AXPVMS GNV V2.1 Layered Product Do you want to continue? [YES]

   
   Continue the procedure by pressing the Enter key for the default (YES). The system responds as shown in the example below. The procedure might take several minutes and numerous messages might be displayed on the screen. In response to each prompt displayed by the system, choose the default answer.

   Configuration phase starting . . .: You will be asked to choose options, if any, for each selected product and for any products that may be installed to satisfy software dependency requirements. DEC AXPVMS GNV V2.1 Do you want the defaults for all options? [YES]

   
   Note that the only option with GNV is whether to include the source files with the installation. The default is YES.
5. Accept the default for all options by pressing the ENTER key. The system responds by asking whether you want to review all the options:

   Do you want to review the options? [NO]

6. Proceed with the GNV installation by pressing the ENTER key to accept the default (NO, skip review of options). The installation proceeds with a progress report on the product installation as in the following example:

   Execution phase starting . . .: The following product will be installed to destination: DEC AXPVMS GNV V2.1 DISK$ALPHASYS:[VMS$COMMON.] Portion done:0%...10%...20%...30%...40%...50%...60%...70% ...80%...90%..100% The following product has been installed: DEC AXPVMS GNV V2.1 Layered Product

   
   When the installation procedure is complete, the system returns you to the DCL prompt ($).
7. Finally, perform the steps described in Section 7 to set up GNV properly.

You can use the PRODUCT INSTALL command to install GNV on a location other than the system disk by specifying the location with the /DESTINATION qualifier. The target disk must be an ODS-5 disk.

The procedure for installing GNV on a location other than the system disk is equivalent to the steps outlined in Section 6.1, except the PRODUCT INSTALL command format in step 3 would be:

$ PRODUCT INSTALL GNV /SOURCE=device-name:[GNV.KIT]
/DESTINATION=device-name

Note that the GNV$STARTUP.COM file is placed in the [SYS$STARTUP] directory on the target disk. You must either copy it to your SYS$COMMON:[SYS$STARTUP] directory or invoke it on the target disk from your SYS$MANAGER:SYSTARTUP_VMS.COM file. For more information on the SYS$STARTUP.COM file, see Section 7.

6.3 If You Move the Target Disk After Installation

The installation procedure creates file GNV_DESTINATION_Alpha.COM or GNV_DESTINATION_IA64.COM in the [SYS$STARTUP] directory. This file points to the target location of the GNV kit, including the physical device specification of the target disk. If you should move the disk on which you installed GNV, edit the SYS$STARTUP:GNV_DESTINATION_archname.COM file so that the device specification correctly reflects the new location.

7 Setup Requirements

GNV provides the following command procedures for use with your system.

1. SYS$STARTUP:GNV$STARTUP.COM --- This file, located in the [SYS$STARTUP] directory of the disk on which you installed GNV, should be executed automatically at startup time. To have it executed at startup time, add the following line to your SYS$MANAGER:SYSTARTUP_VMS.COM file if you installed GNV on the system disk:

   $ @SYS$STARTUP:GNV$STARTUP.COM

   
   If you installed GNV on a disk other than the system disk, add the following line instead, where device-name is the device specification of the disk where GNV was installed.

   $ @device-name:[SYS$STARTUP]GNV$STARTUP.COM

   
   This startup file makes certain required systemwide definitions. Most importantly, it defines the GNU logical to point to the GNV top level directory.
2. GNU:[LIB]GNV_SETUP.COM --- This file is to be executed by each user who will be using GNV. A user can have the file executed automatically at login by incorporating it in the user's LOGIN.COM file. If all users of a system will be using GNV, then this file may be executed in the systemwide LOGIN.COM file: SYS$MANAGER:SYLOGIN.COM.
   This file defines certain process-private symbols that cannot be implemented systemwide. These must be implemented on a per-user basis.
3. SYS$STARTUP:PSX$UP_STARTUP.COM --- This file, located in the [SYS$STARTUP] directory of the disk on which you installed GNV, will be executed automatically at startup time by the GNV$STARTUP.COM procedure. In addition to defining a few logical names to support GNV operation, it also calls the mnt utility to connect all mounted disk volumes under the /mnt directory. If you wish to mount the OpenVMS disks into the Posix view of the file system in a different way, it is recommended that you modify that file by commenting out the call to the DoMountPoints subrouutine, and insert a line which calls your own command procedure with @.

To use GNV, simply enter enter the bash command at the OpenVMS DCL prompt. The bash$ prompt will then appear, as in the following example.

$ bash
bash$

Enter bash commands at this prompt, as shown in the following example, in which the ls command is entered:

bash$ ls

Alternatively, you can enter a single bash command at the OpenVMS DCL prompt, in the following format:

$ bash -c bash-command

For example, to enter the ls command from the OpenVMS DCL prompt, type the following line. After the contents of the working directory are displayed, the OpenVMS DCL prompt appears again.

$ bash -c ls
accountng.dat                         desktop.dir
errorlog.                             app.exe
help.dir

$

If the command you are entering has two or more components, the command and components must be surrounded by double quotes as in the following example:

$ bash -c "ls -al"

This section discusses some of the differences observed between GNV features and utilities on OpenVMS and their counterparts on UNIX systems.

9.1 Root Directory

OpenVMS systems do not have a single root directory similar to that of UNIX systems. The UNIX root directory (/) is the top level of the system file hierarchy. All directories on the system, irrespective of the physical device, are located under the root. On a native OpenVMS system, the closest entity to the UNIX root directory is the toplevel directory of a specific device. The character "/" is not recognized as a directory.

OpenVMS V8.3 has a new feature in the SET ROOT command to specify the location of the root directory. GNV points this root at the primary GNV directory, generally on the system disk. Furthermore, GNV creates a number of directories commonly found immediately under a UNIX root directory: /etc , /usr , /bin , /lib ,. and so forth.

This root directory is the top level of the GNV directory tree. You may use it to locate numerous files and directories. However, unlike a UNIX system, it is not true that all files and directories in the system can be found under the root. To accomplish that, the GNV utility mnt is used to connect all mounted disks to directory entries under the /mnt directory when the

9.2 Multiple Versions of a File

OpenVMS operating systems maintain multiple versions of a file, with the highest version number being the most recent. UNIX maintains only the most recent version of a file. With a few exceptions, GNV supports this UNIX feature. For example, the rm utility removes all versions of a file. The following are some of the utilities that still act only on the most recent version of a file, leaving earlier versions in place:

• mv
• chmod
• chown
• ln

For example, if you use mv to move (or rename) a file, only the highest version number file is moved. The lower versions (older) files are left in place.

9.3 Case Sensitivity in File Names

Normally, OpenVMS systems are not case sensitive. However, on ODS-5 devices you can enable case sensitivity for file names by using the following command at the OpenVMS DCL prompt or in a login command file:

SET PROCESS/CASE=SENSITIVE/PARSE_STYLE=EXTENDED

The following subsections describe differences in the way OpenVMS GNV and the UNIX operating system interpret certain characters and lists characters that are unsupported.

9.4.1 File Names Beginning with a Period

OpenVMS lets you create a file name beginning with a period. The OpenVMS DIRECTORY command will list such files. UNIX systems consider such files as hidden. The UNIX ls command does not list such files unless, for example, the -a option is used or the file name is specified in the command line.

9.4.2 Control Characters

The following control sequences do not work as expected:

• CTRL/C (the response depends on the circumstances; if you do not get the expected response, try using CTRL/Y to bring you to the DCL prompt, and then enter the DCL CONTINUE command to bring you back to the original prompt or interrupted process)
• CTRL/Y (instead of bringing you to the previous command entered, this sequence might bring you back to the DCL prompt, stopping the bash program; try entering CTRL/Y a second time)

The CTRL/@ sequence has not been tested.

10 Reporting Problems

All normal problem-reporting channels are available for GNV users to report problems with the GNV software provided with OpenVMS Alpha and OpenVMS I64. Please note that OpenVMS engineering cannot guarantee resolution of all reported problems in this kit but will do its best to address all reports in a timely manner.

11 Bug Fixes

The latest GNV software includes fixes to bugs found on the indicated version of GNV. The fixes will apply to GNV running on either Alpha or I64 systems, except where specified otherwise.

11.1 Since V2.1

• Installation creates undesired mount points.
  The installed start-up script PSX$UP_STARTUP.COM still includes the DoMountPoints subroutine, but the call to it is commented out. Customers who wish to enable this feature may remove the comment mark.
• Installation on Alpha and Integrity systems in a heterogeneous cluster
  The generated file SYS$STARTUP:GNV_DESTINATION.COM has been replaced by the file SYS$STARTUP:GNV_DESTINATION_archname.COM to avoid conflict.

• CONFIGURE scripts and config.h
  GNV is often used on OpenVMS systems to port and configure OpenSource software. Most OpenSource packages are distributed in source form. A configure script is run to determine the features of the system it is running on, and to configure the build files, especially the make files and one or more include files ( .h ).
  The configure script often generates an include file called config.h . This file contains the results of many of the tests performed by the configure script. The configure script runs numerous tests to determine features implemented by the local system. It then writes records to config.h based on the results of these tests.
  In the past, many of the results written to the config.h file have been wrong. This has been traced to a bug in bash . This problem is resolved in the version of bash shipped with this release of GNV. The problem with bash is illustrated by the following example, where the wrong branch of the if statement was taken.

  echo foo | true if test `eval echo no` = yes then echo Writing to confdefs.h else echo Not writing to anywhere. fi

  
  With this bug fix, configure scripts can be expected to generate more useful config.h files.
• Redirection of DCL commands on OpenVMS I64 systems
  Redirection of DCL commands now works reliably.
  OpenVMS on I64 systems tends to generate mailbox devices with five-digit unit numbers. On Alpha, these unit numbers were limited to four digits. Code used for redirection of DCL commands depended on four-digit unit numbers. For consistency with I64 systems, Alpha unit numbers have been increased to five digits.
• Definition of SYS$POSIX_ROOT
  The GNV startup file (SYS$STARTUP:GNV$STARTUP.COM) defines the logical name SYS$POSIX_ROOT, if that is not already defined. This allows GNV utilities to make use of a UNIX-like system root.
  This release defines SYS$POSIX_ROOT in a format that more closely matches the format expected by RMS. No directory is specified in the definition of this logical.
• Pipe to cut -f bug fixed
  In previous releases of GNV, piping output to a cut -fn command would hang. For example:

  bash$ cat nosuchfile | cut -f2

  
  This problem is resolved in GNV V1.6.

• Pipe operations hang
  Certain forms of pipe operations are known to have problems. For example:

  bash$ (cat t.txt) | less

  
  This command works fine for a small enough t.txt . If the file is larger, the command hangs.
  One workaround to this and certain other pipe hangs is to use the Run-Time Library's feature to increase the buffer size of the mailboxes used to implement pipes, as in the following example:

  $ DEFINE DECC$PIPE_BUFFER_SIZE 65000

  
  Do not use a value much larger than 65000. For example, 65535 does not work.
  For more information, refer to the discussion of the DECC$PIPE_BUFFER_SIZE feature in the Introduction Chapter of the HP C Run-Time Library Reference Manual for OpenVMS Systems.
  This allows the command to work for moderately large files. However, sufficiently large files will still hang.
  Another workaround to the hang is to use a temporary file as in the following example. Of course, this requires editing the script file.

  bash$ (cat t.txt) > s.txt; less s.txt; rm s.txt;

  
  The real problem is that bash should execute both the cat and the less child processes asynchronously. However, it does not currently do this. Instead, the less command does not get processed until the cat has completed. The output of the cat command is buffered in the pipe. If the pipe is not large enough to hold the entire output, then cat waits for the less function to read, but less does not run until the cat function completes. The result is a hang.
  HP is attempting to resolve this problem in a future release of GNV.
• bash Command Line Editing
  There are numerous problems with the bash History File and Command-Line Editing.
  HP hopes to resolve these in some future release of GNV.
• $! shell variable returns a bad process id
  $! is supposed to return the process id of the most recently executed background job. Currently, it instead returns a job number, which is not useful for most purposes.
  HP hopes to resolve this problem in a future release of GNV.

Table 2 lists documentation provided with the GNV kit. Once you have installed the GNV software, you can find the documentation files in the directories indicated.

Table 3 lists sources of information on the Internet.

GNV includes the MAN utility, ported from GNU MAN. Also included are MAN page files for most of the utilities included in the GNV kit. Again, these MAN page files are extracted from GNU sources and might not exactly represent the utilities included with GNV.

In the following table, page counts are provided where appropriate and are approximations.