perlos390 - building and installing Perl for OS/390 and z/OS
This document will help you Configure, build, test and install Perl on OS/390
(aka z/OS) Unix System Services.
This is a fully ported Perl for OS/390 Version 2 Release 3, 5, 6, 7, 8, and 9.
It may work on other versions or releases, but those are the ones we've tested
You may need to carry out some system configuration tasks before running the
Configure script for Perl.
The z/OS Unix Tools and Toys list may prove helpful and contains links to ports
of much of the software helpful for building Perl.
Unpacking Perl distribution on OS/390¶
If using ftp remember to transfer the distribution in binary format.
Gunzip/gzip for OS/390 is discussed at:
to extract an ASCII tar archive on OS/390, try this:
pax -o to=IBM-1047,from=ISO8859-1 -r < latest.tar
zcat latest.tar.Z | pax -o to=IBM-1047,from=ISO8859-1 -r
If you get lots of errors of the form
tar: FSUM7171 ...: cannot set uid/gid: EDC5139I Operation not permitted.
you didn't read the above and tried to use tar instead of pax, you'll first have
to remove the (now corrupt) perl directory
rm -rf perl-...
and then use pax.
Setup and utilities for Perl on OS/390¶
Be sure that your yacc installation is in place including any necessary parser
template files. If you have not already done so then be sure to:
cp /samples/yyparse.c /etc
This may also be a good time to ensure that your /etc/protocol file and either
your /etc/resolv.conf or /etc/hosts files are in place. The IBM document that
described such USS system setup issues was SC28-1890-07 "OS/390 UNIX
System Services Planning", in particular Chapter 6 on customizing the OE
GNU make for OS/390, which is recommended for the build of perl (as well as
building CPAN modules and extensions), is available from the
Some people have reported encountering "Out of memory!" errors while
trying to build Perl using GNU make binaries. If you encounter such trouble
then try to download the source code kit and build GNU make from source to
eliminate any such trouble. You might also find GNU make (as well as Perl and
Apache) in the red-piece/book "Open Source Software for OS/390
UNIX", SG24-5944-00 from IBM.
If instead of the recommended GNU make you would like to use the system supplied
make program then be sure to install the default rules file properly via the
cp /samples/startup.mk /etc
and be sure to also set the environment variable _C89_CCMODE=1 (exporting
_C89_CCMODE=1 is also a good idea for users of GNU make).
You might also want to have GNU groff for OS/390 installed before running the
"make install" step for Perl.
There is a syntax error in the /usr/include/sys/socket.h header file that IBM
supplies with USS V2R7, V2R8, and possibly V2R9. The problem with the header
file is that near the definition of the SO_REUSEPORT constant there is a
spurious extra '/' character outside of a comment like so:
#define SO_REUSEPORT 0x0200 /* allow local address & port
reuse */ /
You could edit that header yourself to remove that last '/', or you might note
that Language Environment (LE) APAR PQ39997 describes the problem and PTF's
UQ46272 and UQ46271 are the (R8 at least) fixes and apply them. If left
unattended that syntax error will turn up as an inability for Perl to build
its "Socket" extension.
For successful testing you may need to turn on the sticky bit for your world
readable /tmp directory if you have not already done so (see man chmod).
Configure Perl on OS/390¶
Once you've unpacked the distribution, run "sh Configure" (see INSTALL
for a full discussion of the Configure options). There is a "hints"
file for os390 that specifies the correct values for most things. Some things
to watch out for include:
- A message of the form:
(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.)
is nothing to worry about at all.
- Some of the parser default template files in /samples are needed in /etc.
In particular be sure that you at least copy /samples/yyparse.c to /etc
before running Perl's Configure. This step ensures successful extraction
of EBCDIC versions of parser files such as perly.c, perly.h, and
x2p/a2p.c. This has to be done before running Configure the first time. If
you failed to do so then the easiest way to re-Configure Perl is to delete
your misconfigured build root and re-extract the source from the tar ball.
Then you must ensure that /etc/yyparse.c is properly in place before
attempting to re-run Configure.
- This port will support dynamic loading, but it is not selected by default.
If you would like to experiment with dynamic loading then be sure to
specify -Dusedl in the arguments to the Configure script. See the comments
in hints/os390.sh for more information on dynamic loading. If you build
with dynamic loading then you will need to add the $archlibexp/CORE
directory to your LIBPATH environment variable in order for perl to work.
See the config.sh file for the value of $archlibexp. If in trying to use
Perl you see an error message similar to:
CEE3501S The module libperl.dll was not found.
From entry point __dllstaticinit at compile unit offset +00000194 at
then your LIBPATH does not have the location of libperl.x and either
libperl.dll or libperl.so in it. Add that directory to your LIBPATH and
- Do not turn on the compiler optimization flag "-O". There is a
bug in either the optimizer or perl that causes perl to not work correctly
when the optimizer is on.
- Some of the configuration files in /etc used by the networking APIs are
either missing or have the wrong names. In particular, make sure that
there's either an /etc/resolv.conf or an /etc/hosts, so that
gethostbyname() works, and make sure that the file /etc/proto has
been renamed to /etc/protocol (NOT /etc/protocols, as used by other Unix
systems). You may have to look for things like HOSTNAME and DOMAINORIGIN
in the "//'SYS1.TCPPARMS(TCPDATA)'" PDS member in order to
properly set up your /etc networking files.
Build, Test, Install Perl on OS/390¶
if everything looks ok (see the next section for test/IVP diagnosis) then:
this last step may or may not require UID=0 privileges depending on how you
answered the questions that Configure asked and whether or not you have write
access to the directories you specified.
Build Anomalies with Perl on OS/390¶
"Out of memory!" messages during the build of Perl are most often
fixed by re building the GNU make utility for OS/390 from a source code kit.
Another memory limiting item to check is your MAXASSIZE parameter in your
'SYS1.PARMLIB(BPXPRMxx)' data set (note too that as of V2R8 address space
limits can be set on a per user ID basis in the USS segment of a RACF
profile). People have reported successful builds of Perl with MAXASSIZE
parameters as small as 503316480 (and it may be possible to build Perl with a
MAXASSIZE smaller than that).
Within USS your /etc/profile or $HOME/.profile may limit your ulimit settings.
Check that the following command returns reasonable values:
To conserve memory you should have your compiler modules loaded into the Link
Pack Area (LPA/ELPA) rather than in a link list or step lib.
If the c89 compiler complains of syntax errors during the build of the Socket
extension then be sure to fix the syntax error in the system header
Testing Anomalies with Perl on OS/390¶
The "make test" step runs a Perl Verification Procedure, usually
before installation. You might encounter STDERR messages even during a
successful run of "make test". Here is a guide to some of the more
commonly seen anomalies:
- A message of the form:
io/openpid...........CEE5210S The signal SIGHUP was received.
CEE5210S The signal SIGHUP was received.
CEE5210S The signal SIGHUP was received.
indicates that the t/io/openpid.t test of Perl has passed but done so with
extraneous messages on stderr from CEE.
- A message of the form:
lib/ftmp-security....File::Temp::_gettemp: Parent directory (/tmp/) is not safe
(sticky bit not set when world writable?) at lib/ftmp-security.t line 100
File::Temp::_gettemp: Parent directory (/tmp/) is not safe (sticky bit not
set when world writable?) at lib/ftmp-security.t line 100
indicates a problem with the permissions on your /tmp directory within the
HFS. To correct that problem issue the command:
chmod a+t /tmp
from an account with write access to the directory entry for /tmp.
- Out of Memory!
Recent perl test suite is quite memory hungry. In addition to the comments
above on memory limitations it is also worth checking for _CEE_RUNOPTS in
your environment. Perl now has (in miniperlmain.c) a C #pragma to set CEE
run options, but the environment variable wins.
The C code asks for:
#pragma runopts(HEAP(2M,500K,ANYWHERE,KEEP,8K,4K) STACK(,,ANY,) ALL31(ON))
The important parts of that are the second argument (the increment) to HEAP,
and allowing the stack to be "Above the (16M) line". If the heap
increment is too small then when perl (for example loading
unicode/Name.pl) tries to create a "big" (400K+) string it
cannot fit in a single segment and you get "Out of Memory!" -
even if there is still plenty of memory available.
A related issue is use with perl's malloc. Perl's malloc uses
"sbrk()" to get memory, and "sbrk()" is limited to the
first allocation so in this case something like:
is needed to get through the test suite.
Installation Anomalies with Perl on OS/390¶
The installman script will try to run on OS/390. There will be fewer errors if
you have a roff utility installed. You can obtain GNU groff from the Redbook
SG24-5944-00 ftp site.
Usage Hints for Perl on OS/390¶
When using perl on OS/390 please keep in mind that the EBCDIC and ASCII
character sets are different. See perlebcdic.pod for more on such character
set issues. Perl builtin functions that may behave differently under EBCDIC
are also mentioned in the perlport.pod document.
Open Edition (UNIX System Services) from V2R8 onward does support
#!/path/to/perl script invocation. There is a PTF available from IBM for V2R7
that will allow shell/kernel support for #!. USS releases prior to V2R7 did
not support the #! means of script invocation. If you are running V2R6 or
earlier then see:
head `whence perldoc`
for an example of how to use the "eval exec" trick to ask the shell to
have Perl run your scripts on those older releases of Unix System Services.
If you are having trouble with square brackets then consider switching your
rlogin or telnet client. Try to avoid older 3270 emulators and ISHELL for
working with Perl on USS.
Floating Point Anomalies with Perl on OS/390¶
There appears to be a bug in the floating point implementation on S/390 systems
such that calling int()
on the product of a number and a small
magnitude number is not the same as calling int()
on the quotient of
that number and a large magnitude number. For example, in the following Perl
my $x = 100000.0;
my $y = int($x * 1e-5) * 1e5; # '0'
my $z = int($x / 1e+5) * 1e5; # '100000'
print "\$y is $y and \$z is $z\n"; # $y is 0 and $z is 100000
Although one would expect the quantities $y and $z to be the same and equal to
100000 they will differ and instead will be 0 and 100000 respectively.
The problem can be further examined in a roughly equivalent C program:
double x = 100000.0;
double y = 0.0;
double z = 0.0;
x = 100000.0 * 1e-5;
r1 = modf (x,&y);
x = 100000.0 / 1e+5;
r2 = modf (x,&z);
printf("y is %e and z is %e\n",y*1e5,z*1e5);
/* y is 0.000000e+00 and z is 1.000000e+05 (with c89) */
Modules and Extensions for Perl on OS/390¶
Pure pure (that is non xs) modules may be installed via the usual:
If 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 the default
static linking you can still build xs based extensions for OS/390 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:
make -f Makefile.aperl inst_perl MAP_TARGET=perl
In most cases people have reported better results with GNU make rather than the
system's /bin/make program, whether for plain modules or for xs based
If the make process encounters trouble with either compilation or linking then
try setting the _C89_CCMODE to 1. Assuming sh is your login shell then run:
If tcsh is your login shell then use the setenv command.
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.
INSTALL, perlport, perlebcdic, ExtUtils::MakeMaker.
Mailing list for Perl on OS/390¶
If you are interested in the z/OS (formerly known as OS/390) and POSIX-BC
(BS2000) ports of Perl then see the perl-mvs mailing list. To subscribe, send
an empty message to firstname.lastname@example.org.
There are web archives of the mailing list at:
This document was originally written by David Fiander for the 5.005 release of
This document was podified for the 5.005_03 release of Perl 11 March 1999.
Updated 28 November 2001 for broken URLs.
Updated 12 November 2000 for the 5.7.1 release of Perl.
Updated 15 January 2001 for the 5.7.1 release of Perl.
Updated 24 January 2001 to mention dynamic loading.
Updated 12 March 2001 to mention //'SYS1.TCPPARMS(TCPDATA)'.