If you read this file _as_is_, just ignore the equal signs on the left.
This file is written in the POD format (see [.POD]PERLPOD.POD;1) which is
specially designed to be readable as is.
README.vms - Configuring, building, testing, and installing perl on VMS
To configure, build, test, and install perl on VMS:
mmk may be used in place of mms in the last three steps.
=head2 Important safety tip
The build and install procedures have changed significantly from the 5.004
releases! Make sure you read the "Configuring the Perl Build", "Building
Perl", and "Installing Perl" sections of this document before you build or
Also note that, as of Perl version 5.005 and later, an ANSI C compliant
compiler is required to build Perl. VAX C is *not* ANSI compliant, as it
died a natural death some time before the standard was set. Therefore
VAX C will not compile perl 5.005. We are sorry about that.
If you are stuck without DEC C (the VAX C license should be good for DEC C,
but the media charges might prohibit an upgrade), consider getting Gnu C
The VMS port of Perl is as functionally complete as any other Perl port
(and as complete as the ports on some Unix systems). The Perl binaries
provide all the Perl system calls that are either available under VMS or
reasonably emulated. There are some incompatibilities in process handling
(e.g. the fork/exec model for creating subprocesses doesn't do what you
might expect under Unix), mainly because VMS and Unix handle processes and
sub-processes very differently.
There are still some unimplemented system functions, and of course we
could use modules implementing useful VMS system services, so if you'd like
to lend a hand we'd love to have you. Join the Perl Porting Team Now!
The current sources and build procedures have been tested on a VAX using
DEC C, and on an AXP using DEC C. If you run into problems with
other compilers, please let us know.
There are issues with various versions of DEC C, so if you're not running a
relatively modern version, check the "DEC C issues" section later on in this
=head2 Other required software
In addition to VMS and DCL you will need two things:
=item 1 A C compiler.
DEC C or gcc for VMS (AXP or VAX).
=item 2 A make tool.
DEC's MMS (v2.6 or later), or MadGoat's free MMS
analog MMK (available from ftp.madgoat.com/madgoat) both work
just fine. Gnu Make might work, but it's been so long since
anyone's tested it that we're not sure. MMK is free though, so
go ahead and use that.
=head2 Additional software that is optional
You may also want to have on hand:
=item 1 GUNZIP/GZIP.EXE for VMS
A de-compressor for *.gz and *.tgz files available from a number
of web/ftp sites.
=item 2 VMS TAR
For reading and writing unix tape archives (*.tar files). Vmstar is also
available from a number of web/ftp sites.
=item 3 UNZIP.EXE for VMS
A combination decompressor and archive reader/writer for *.zip files.
Unzip is available from a number of web/ftp sites.
=item 4 MOST
Most is an optional pager that is convenient to use with perldoc (unlike
TYPE/PAGE, MOST can go forward and backwards in a document and supports
regular expression searching). Most builds with the slang
library on VMS. Most and slang are available from:
Please note that UNZIP and GUNZIP are not the same thing (they work with
different formats). Many of the useful files from CPAN (the Comprehensive
Perl Archive Network) are in *.tar.gz format (this includes copies of the
source code for perl as well as modules and scripts that you may wish to
add later) hence you probably want to have GUNZIP.EXE and VMSTAR.EXE on
your VMS machine.
If you want to include socket support, you'll need a TCP/IP stack and either
DEC C, or socket libraries. See the "Socket Support (optional)" topic
for more details.
=head1 Configuring the Perl build
To configure perl (a necessary first step), issue the command
from the top of an unpacked perl source directory. You will be asked a
series of questions, and the answers to them (along with the capabilities
of your C compiler and network stack) will determine how perl is custom
built for your machine.
If you have multiple C compilers installed, you'll have your choice of
which one to use. Various older versions of DEC C had some caveats, so if
you're using a version older than 5.2, check the "DEC C Issues" section.
If you have any symbols or logical names in your environment that may
interfere with the build or regression testing of perl then configure.com
will try to warn you about them. If a logical name is causing
you trouble but is in an LNM table that you do not have write access to
then try defining your own to a harmless equivalence string in a table
such that it is resolved before the other (e.g. if TMP is defined in the
SYSTEM table then try DEFINE TMP "NL:" or somesuch in your process table)
otherwise simply deassign the dangerous logical names. The potentially
troublesome logicals and symbols are:
As a handy shortcut, the command:
@ Configure "-des"
(note the quotation marks and case) will choose reasonable defaults
automatically (it takes DEC C over Gnu C, DEC C sockets over SOCKETSHR
sockets, and either over no sockets). More help with configure.com is
@ Configure "-h"
See the "Changing compile-time options (optional)" section below to learn
even more details about how to influence the outcome of the important
configuration step. If you find yourself reconfiguring and rebuilding
then be sure to also follow the advice in the "Cleaning up and starting
fresh (optional)" and the checklist of items in the "CAVEATS" sections
=head2 Changing compile-time options (optional)
Most of the user definable features of Perl are enabled or disabled in
[.VMS]CONFIG.VMS. There is code in there to Do The Right Thing, but that
may end up being the wrong thing for you. Make sure you understand what
you are doing since inappropriate changes to CONFIG.VMS can render perl
Odds are that there's nothing here to change, unless you're on a version of
VMS later than 6.2 and DEC C later than 5.6. Even if you are, the correct
values will still be chosen, most likely. Poking around here should be
The one exception is the various *DIR install locations. Changing those
requires changes in genconfig.pl as well. Be really careful if you need to
change these, as they can cause some fairly subtle problems.
=head2 Socket Support (optional)
Perl includes a number of functions for IP sockets, which are available if
you choose to compile Perl with socket support. Since IP networking is an
optional addition to VMS, there are several different IP stacks available.
How well integrated they are into the system depends on the stack, your
version of VMS, and the version of your C compiler.
The most portable solution uses the SOCKETSHR library. In combination with
either UCX or NetLib, this supports all the major TCP stacks (Multinet,
Pathways, TCPWare, UCX, and CMU) on all versions of VMS Perl runs on, with
all the compilers on both VAX and Alpha. The socket interface is also
consistent across versions of VMS and C compilers. It has a problem with
UDP sockets when used with Multinet, though, so you should be aware of
The other solution available is to use the socket routines built into DEC
C. Which routines are available depend on the version of VMS you're
running, and require proper UCX emulation by your TCP/IP vendor.
Relatively current versions of Multinet, TCPWare, Pathway, and UCX all
provide the required libraries--check your manuals or release notes to see
if your version is new enough.
=head1 Building Perl
The configuration script will print out, at the very end, the MMS or MMK
command you need to compile perl. Issue it (exactly as printed) to start
Once you issue your MMS or MMK command, sit back and wait. Perl should
compile and link without a problem. If a problem does occur check the
"CAVEATS" section of this document. If that does not help send some
mail to the VMSPERL mailing list. Instructions are in the "Mailing Lists"
section of this document.
=head1 Testing Perl
Once Perl has built cleanly you need to test it to make sure things work.
This step is very important since there are always things that can go wrong
somehow and yield a dysfunctional Perl for you.
Testing is very easy, though, as there's a full test suite in the perl
distribution. To run the tests, enter the *exact* MMS line you used to
compile Perl and add the word "test" to the end, like this:
If the compile command was:
then the test command ought to be:
MMS (or MMK) will run all the tests. This may take some time, as there are
a lot of tests. If any tests fail, there will be a note made on-screen.
At the end of all the tests, a summary of the tests, the number passed and
failed, and the time taken will be displayed.
If any tests fail, it means something is wrong with Perl. If the test suite
hangs (some tests can take upwards of two or three minutes, or more if
you're on an especially slow machine, depending on your machine speed, so
don't be hasty), then the test *after* the last one displayed failed. Don't
install Perl unless you're confident that you're OK. Regardless of how
confident you are, make a bug report to the VMSPerl mailing list.
If one or more tests fail, you can get more information on the failure by
issuing this command sequence:
@ [.VMS]TEST .typ "" "-v" [.subdir]test.T
where ".typ" is the file type of the Perl images you just built (if you
didn't do anything special, use .EXE), and "[.subdir]test.T" is the test
that failed. For example, with a normal Perl build, if the test indicated
that [.op]time failed, then you'd do this:
@ [.VMS]TEST .EXE "" "-v" [.OP]TIME.T
When you send in a bug report for failed tests, please include the output
from this command, which is run from the main source directory:
MCR MINIPERL "-V"
Note that -"V" really is a capital V in double quotes. This will dump out a
couple of screens worth of configuration information, and can help us
diagnose the problem. If (and only if) that did not work then try enclosing
the output of:
If (and only if) that did not work then try enclosing the output of:
You may also be asked to provide your C compiler version ("CC/VERSION NL:"
with DEC C, "gcc --version" with GNU CC). To obtain the version of MMS or
MMK you are running try "MMS/ident" or "MMK /ident". The GNU make version
can be identified with "make --version".
=head2 Cleaning up and starting fresh (optional)
If you need to recompile from scratch, you have to make sure you clean up
first. There is a procedure to do it--enter the *exact* MMS line you used
to compile and add "realclean" at the end, like this:
if the compile command was:
then the cleanup command ought to be:
If you do not do this things may behave erratically during the subsequent
rebuild attempt. They might not, too, so it is best to be sure and do it.
=head1 Installing Perl
There are several steps you need to take to get Perl installed and
Check your default file protections with
SHOW PROTECTION /DEFAULT
and adjust if necessary with SET PROTECTION=(code)/DEFAULT.
Create a directory somewhere and either run @perl_setup or
define the concealed logical PERL_ROOT to point to it by hand.
SHOW LOGICAL PERL_ROOT
DEFINE/TRANS=(CONC,TERM) PERL_ROOT dka200:[perl.]
Run the install script via:
If for some reason it complains about target INSTALL being up to date,
throw a /FORCE switch on the MMS or MMK command.
The DCL script PERL_SETUP.COM that is written by CONFIGURE.COM
will help you with the definition of PERL_ROOT, PERLSHR and the PERL
Foreign symbol. Take a look at PERL_SETUP.COM and modify it if you want
to. Then copy PERL_SETUP.COM to a place accessible to your perl users.
COPY PERL_SETUP.COM SYS$LIBRARY:
If you want to have everyone on the system have access to perl
then add a line that reads
Two alternatives to the foreign symbol would be to install PERL into
DCLTABLES.EXE (Check out the section "Installing Perl into DCLTABLES
(optional)" for more information), or put the image in a
directory that's in your DCL$PATH (if you're using VMS V6.2 or higher).
An alternative to having PERL_SETUP.COM define the PERLSHR logical name
is to simply copy it into the system shareable library directory with:
copy perl_root:perlshr.exe sys$share:
See also the "INSTALLing images (optional)" section.
=head2 Installing Perl into DCLTABLES (optional)
Execute the following command file to define PERL as a DCL command.
You'll need CMKRNL privilege to install the new dcltables.exe.
$ create perl.cld
! modify to reflect location of your perl.exe
define verb perl
$ set command perl /table=sys$common:[syslib]dcltables.exe -
$ install replace sys$common:[syslib]dcltables.exe
=head2 INSTALLing images (optional)
On systems that are using perl quite a bit, and particularly those with
minimal RAM, you can boost the performance of perl by INSTALLing it as
a known image. PERLSHR.EXE is typically larger than 2000 blocks
and that is a reasonably large amount of IO to load each time perl is
INSTALL ADD PERLSHR/SHARE
INSTALL ADD PERL/HEADER
should be enough for PERLSHR.EXE (/share implies /header and /open),
while /HEADER should do for PERL.EXE (perl.exe is not a shared image).
If your code 'use's modules, check to see if there is a shareable image for
them, too. In the base perl build, POSIX, IO, Fcntl, Opcode, SDBM_File,
DCLsym, and Stdio all have shared images that can be installed /SHARE.
How much of a win depends on your memory situation, but if you are firing
off perl with any regularity (like more than once every 20 seconds or so)
it is probably beneficial to INSTALL at least portions of perl.
While there is code in perl to remove privileges as it runs you are advised
to NOT INSTALL PERL.EXE with PRIVs!
=head1 Reporting Bugs
If you come across what you think might be a bug in Perl, please report
it. There's a script in PERL_ROOT:[UTILS], perlbug, that walks you through
the process of creating a bug report. This script includes details of your
installation, and is very handy. Completed bug reports should go to
Probably the single biggest gotcha in compiling Perl is giving the wrong
switches to MMS/MMK when you build. Use *exactly* what the configure.com
The next big gotcha is directory depth. Perl can create directories four,
five, or even six levels deep during the build, so you don't have to be
too deep to start to hit the RMS 8 level limit (for versions of VMS prior
to V7.2 and even with V7.2 on the VAX). It is best to do
DEFINE/TRANS=(CONC,TERM) PERLSRC "disk:[dir.dir.dir.perldir.]"
SET DEFAULT PERLSRC:
before building in cases where you have to unpack the distribution so deep
(note the trailing period in the definition of PERLSRC). Perl modules
from CPAN can be just as bad (or worse), so watch out for them, too. Perl's
configuration script will warn if it thinks you are too deep (at least on
a VAX or on Alpha versions of VMS prior to 7.2). But MakeMaker will not
warn you if you start out building a module too deep in a directory.
Be sure that the process that you use to build perl has a PGFLQ greater
than 100000. Be sure to have a correct local time zone to UTC offset
defined (in seconds) in the logical name SYS$TIMEZONE_DIFFERENTIAL before
running the regression test suite. The SYS$MANAGER:UTC$CONFIGURE_TDF.COM
procedure will help you set that logical for your system but may require
system privileges. For example, a location 5 hours west of UTC (such as
the US East coast while not on daylight savings time) would have:
DEFINE SYS$TIMEZONE_DIFFERENTIAL "-18000"
A final thing that causes trouble is leftover pieces from a failed
build. If things go wrong make sure you do a "(MMK|MMS|make) realclean"
before you rebuild.
=head2 DEC C issues
Note to DEC C users: Some early versions (pre-5.2, some pre-4. If you're DEC
C 5.x or higher, with current patches if any, you're fine) of the DECCRTL
contained a few bugs which affect Perl performance:
=item - pipes
Newlines are lost on I/O through pipes, causing lines to run together.
This shows up as RMS RTB errors when reading from a pipe. You can
work around this by having one process write data to a file, and
then having the other read the file, instead of the pipe. This is
fixed in version 4 of DEC C.
=item - modf()
The modf() routine returns a non-integral value for some values above
INT_MAX; the Perl "int" operator will return a non-integral value in
these cases. This is fixed in version 4 of DEC C.
=item - ALPACRT ECO
On the AXP, if SYSNAM privilege is enabled, the CRTL chdir() routine
changes the process default device and directory permanently, even
though the call specified that the change should not persist after
Perl exited. This is fixed by DEC CSC patch ALPACRT04_061 or later.
Please note that in later versions "DEC C" may also be known as
=head2 GNU issues
It has been a while since the GNU utilities such as GCC or GNU make
were used to build perl on VMS. Hence they may require a great deal
of source code modification to work again.
=head1 Mailing Lists
There are several mailing lists available to the Perl porter. For VMS
specific issues (including both Perl questions and installation problems)
there is the VMSPERL mailing list. It is usually a low-volume (10-12
messages a week) mailing list.
The subscription address is MAJORDOMO@PERL.ORG. Send a mail message with
just the words SUBSCRIBE VMSPERL in the body of the message.
The VMSPERL mailing list address is VMSPERL@PERL.ORG. Any mail sent there
gets echoed to all subscribers of the list. There is a searchable archive of
the list on the web at:
To unsubscribe from VMSPERL send the message UNSUBSCRIBE VMSPERL to
MAJORDOMO@PERL.ORG. Be sure to do so from the subscribed account that
you are canceling.
=head2 Web sites
Vmsperl pages on the web include:
=head1 SEE ALSO
Perl information for users and programmers about the port of perl to VMS is
available from the [.VMS]PERLVMS.POD file that gets installed as L.
For administrators the perlvms document also includes a detailed discussion
of extending vmsperl with CPAN modules after Perl has been installed.
Last revised 25-February-2000 by Peter Prymmer firstname.lastname@example.org.
Revised 27-October-1999 by Craig Berry email@example.com.
Revised 01-March-1999 by Dan Sugalski firstname.lastname@example.org.
Originally by Charles Bailey email@example.com.
A real big thanks needs to go to Charles Bailey
firstname.lastname@example.org, who is ultimately responsible for Perl 5.004
running on VMS. Without him, nothing the rest of us have done would be at
There are, of course, far too many people involved in the porting and testing
of Perl to mention everyone who deserves it, so please forgive us if we've
missed someone. That said, special thanks are due to the following:
Tim Adye T.J.Adye@rl.ac.uk
for the VMS emulations of getpw*()
David Denholm email@example.com
for extensive testing and provision of pipe and SocketShr code,
Mark Pizzolato firstname.lastname@example.org
for the getredirection() code
Rich Salz email@example.com
for readdir() and related routines
Peter Prymmer firstname.lastname@example.org
for extensive testing, as well as development work on
configuration and documentation for VMS Perl,
Dan Sugalski email@example.com
for extensive contributions to recent version support,
development of VMS-specific extensions, and dissemination
of information about VMS Perl,
the Stanford Synchrotron Radiation Laboratory and the
Laboratory of Nuclear Studies at Cornell University for
the opportunity to test and develop for the AXP,
John Hasstedt John.Hasstedt@sunysb.edu
for VAX VMS V7.2 support
and to the entire VMSperl group for useful advice and suggestions. In
addition the perl5-porters deserve credit for their creativity and
willingness to work with the VMS newcomers. Finally, the greatest debt of
gratitude is due to Larry Wall firstname.lastname@example.org, for having the ideas which
have made our sleepless nights possible.
The VMSperl group