perlos390 - building and installing Perl for z/OS (previously called OS/390)
This document will help you Configure, build, test and install Perl on z/OS Unix System Services.
Perl 5.44 on z/OS has been tested on z/OS 3.1 using "Unix System Services". There have been extensive changes in the build process (such as using a different compiler) from earlier releases, which were tested on earlier versions of z/OS. It could well be that this release of Perl will work on different z/OS versions.
The native character set for z/OS is EBCDIC (code page 1047 in North America), but recent z/OS releases have added the ability for it to handle ASCII as well. And an open source project now exists to port many open source tools, such as git, and yes Perl to take advantage of these new capabilities. (A blog post about its early development is here https://makingdeveloperslivesbetter.wordpress.com/2022/01/18/enabling-open-source-for-z-os-perl/.)
Hiding a machine's character set without sacrificing too much performance requires extensive wizardry, not all of which is transparent, and not all of which yet works. The project is being actively developed with significant contributions by IBM of staff and machine time. The project is called Open Source for z/OS. https://zopen-community brings you to its landing page.
Basically, files and streams need to have extra information about their character set. This can easily require manual intervention to get things to work. For background, including what steps you must do to get this to work on your inputs, see https://makingdeveloperslivesbetter.wordpress.com/2022/01/07/is-z-os-ascii-or-ebcdic-yes/
You can obtain this Perl port at https://zopen-community/perlport. At the moment this is written, one configuration of perl is available: dynamic loading, unthreaded, non-debugging. You can customize it to some extent by modifying the file buildenv. Refer to "Configuring perl" below for hints on that. Also, refer to "Known Bugs" below.
The rest of this document describes how to build a perl that runs native EBCDIC on z/OS.
z/OS Unix System Services has a native shell much like ksh or bash, and Unix commands that are similar to ones in Linux, such as sed. Available options for these may differ from the Linux ones.
There aren't any known 32-bit z/OS systems in existence anymore, so this document describes how to build a 64-bit EBCDIC Perl.
Most CPAN modules have been written assuming ASCII. They may or may not work on EBCDIC. What we have found is that many do work, either mostly or completely, but may not appear to pass all their tests. Often the failures are in edge cases that may not come up in mainstream uses. Also any given failure may not actually be a real failure, but a problem with the test. This is because the typical test compares results with expected values which the test's author often hard-coded assuming ASCII, so the test is wrong, and the code is correct. Also, some failures may not be important for you. For example, if you do a plain sort, ASCII will have the digits first, uppercase letters next, and lowercase last. EBCDIC sorts the opposite. If your application really needs ASCII ordering, the module won't give the proper results; but often you just need a consistent sorting, and for that purpose the module could work perfectly well.
Perl itself is shipped with some CPAN modules included. Some of these do not yet work fully on EBCDIC, and therefore testing of them is suppressed. See "Bugs only in the EBCDIC mode"
The tools required for building perl are available as:
native commands on z/OS
z/OS has versions of many tools that come with the Linux OS. Some of these don't have as many options as replacements available in the next group:
through the zopen community
gunzip and clang for example. Also you can get bash itself.
at no cost from IBM
https://www.ibm.com/products/open-enterprise-foundation-zos. These include GNU make, which you will need.
You'll first need a tarball. At the moment this is written, there are no EBCDIC tarballs published, but it is easy to create one given that you have access to a system with any relatively modern perl.
Get an ASCII tarball. Choose one of the following:
Go to https://www.perl.org/get.html and choose any one of the "Download latest Linuxy stable source" buttons. The name of that tarball will be something like perl-V.R.M,tar,gz, where V.R.M is the version/release/modification of the perl you are downloading. Do
gunzip perl-V.R.M.tar.gz
pax -r -f perl-V.R.M.tar(or tar instead of pax)
This will create a directory named perl-V.R.M, which you can rename to be whatever you want. The instructions below assume you choose perl.
If instead you want the latest unstable development release, clone Perl:
git clone https://github.com/Perl/perl5.git perlEither way, after getting the perl directory populated, do
cd perl
perl Porting/makerel -eThis will use whatever perl already is on the system to create an EBCDIC tarball named perl-V.R.M.tar.gz.
Use scp or sftp to copy the tarball to the target z/OS system. Then, from the directory where it is located, do
gunzip perl-V.R.M.tar.gz
pax -r -f perl-V.R.M.tar
mv perl-V.R.M perl
cd perl(You likely can't use tar instead of pax here.)
Now it is time to Configure it to your needs. If you need a dynamically loading perl (see below), first do:
export PATH=$PWD:$PATH
export LIBPATH=$PWD:$LIBPATHThen run Configure
./Configure -Dprefix=/path-to/install/directory -des \
OTHER-OPTIONS-AS-BELOW-d means to use the default configuration values. This is important, as we have set those up specifically for z/OS.
-e means to continue on to the bitter end, not stopping the process early.
-s means to avoid unnecessary output verbiage. This parameter is optional.
If the perl is an unstable development release, add -Dusedevel as one of the OTHER-OPTIONS-AS-BELOW
If you think you may want to debug the perl, add -DDEBUGGING -Aoptimize=-g3 -Aoptimize=-ggdb3.
To silence some unnecessary compilation warnings, you can add -Accflags=-Wno-deprecated.
To optimize the resultant perl binary, add -Aoptimize=-O2, or -O3, both of which have been tested on z/OS 3.1.
If you will want to use modules from CPAN (like DBI (and DBDs), JSON::XS, and Text::CSV_XS), consider using dynamic loading. This isn't necessary if all such modules you might want are written only in Perl, but if some of them are compiled (meaning they contain XS code), you'll either need to recompile all of perl when you add one, or set it up initially to use dynamic loading. To do this, add -Dusedl to the Configure options.
When Configure is run using the z/OS native shell, you'll see a message like
(I see you are using the Korn shell. Some ksh's blow up on Configure,
mainly on older exotic systems. If yours does, try the Bourne shell
instead.)The native shell looks like ksh, and it works fine, so just ignore the message.
Configure currently will output errors in finding the header dependencies various object files have. This just means that they may be recompiled unnecessarily.
Run GNU make to build Perl
makeThis will currently likely crash in making the Encode module. To work around that, execute the following command
chtag -tc IBM-1047 cpan/Encode/Makefileand rerun make. You may have to repeat this a second time.
TEST_JOBS=n make test_harnesswhere n is the number of tests to run in parallel. On hardware that is single core, 2 or 3 work well. A common value (if you aren't crowding out other users) is to set n to twice the number of cores available, plus 1.
Some tests currently fail.
The failing tests in Test-Simple, Pod-Html, op/signatures, and io/nargv.t are false alarms.
If zopen is installed on your machine, it is important to get the PATH variable correct. When running the zopen port of Perl, its directories should come first. When running the EBCDIC perl, the zopen directories should either not be in the PATH variable, or come last. For example, /bin/echo needs to have precedence over the zopen version in this case.
ExtUtils::MakeMaker does not work properly on perls built for dynamic loading.
Some cpan modules shipped with perl do not yet work fully on EBCDIC, and therefore testing of them is suppressed. You can see which by examining t/TEST and searching for EBCDIC. Almost all of the problems with these are in the cases where their input is from some other encoding. These could be because they communicate with a remote ASCII system, or read from a file containing some other encoding. So, for example, Pod::Simple works fine on files encoded in EBCDIC, but will fail miserably for files encoded in a Cyrillic encoding.
Fixes for these are under active development.
Currently, in the zopen port of Perl, there are some issues when using UTF-8 locales; some of these lead to segfaults.
make installwill install perl into the directory you gave in the command
./Configure -Dprefix=/path-to/install/directory ...Perl is now built using the clang compiler. Previous releases used different compilers, and for them, optimization seemed iffy, so we recommended against doing it. (And we didn't revisit that advice with newer releases to see if things had gotten fixed, so that recommendation may have been outdated.) But with clang it does seem to work, and "Configuring perl" above gives instructions for enabling it.
Pure Perl (that is non XS) modules may be installed via the usual:
perl Makefile.PL
make
make test
make installIf you built perl with dynamic loading capability, then that would also be the way to build XS based extensions. However, if you built perl with static linking you can still build XS based extensions for z/OS but you will need to follow the instructions in ExtUtils::MakeMaker for building statically linked perl binaries. In the simplest configurations building a static perl + XS extension boils down to:
perl Makefile.PL
make
make perl
make test
make install
make -f Makefile.aperl inst_perl MAP_TARGET=perlTo run the 64-bit Dynamic Perl environment, update your PATH and LIBPATH to include the location you installed Perl into, and then run the perl you installed as perlV.R.M where V/R/M is the Version/Release/Modification level of the current development level.
David Fiander and Peter Prymmer with thanks to Dennis Longnecker and William Raffloer for valuable reports, LPAR and PTF feedback. Thanks to Mike MacIsaac and Egon Terwedow for SG24-5944-00. Thanks to Ignasi Roca for pointing out the floating point problems. Thanks to John Goodyear for dynamic loading help.
Mike Fulton and Karl Williamson have provided updates for UTF8, DLL, 64-bit and ASCII/EBCDIC Bi-Modal support
Updated 25 May 2026 to reflect Perl v5.44 and https://zopen-community.
Updated 24 December 2021 to enable initial ASCII support.
Updated 03 October 2019 for perl-5.33.3+
Updated 28 November 2001 for broken URLs.
Updated 12 March 2001 to mention //'SYS1.TCPPARMS(TCPDATA)'.
Updated 24 January 2001 to mention dynamic loading.
Updated 15 January 2001 for the 5.7.1 release of Perl.
Updated 12 November 2000 for the 5.7.1 release of Perl.
This document was podified for the 5.005_03 release of Perl 11 March 1999.
This document was originally written by David Fiander for the 5.005 release of Perl.