perlos2 - Perl under OS/2, DOS, Win0.3*, Win0.95 and
WinNT.
SYNOPSIS
One can read this document in the following formats:
man perlos2
view perl perlos2
explorer perlos2.html
info perlos2
to list some (not all may be available simultaneously), or
it may be read as is: either as README.os2, or pod/per
los2.pod.
To read the .INF version of documentation (very recom
mended) outside of OS/2, one needs an IBM's reader (may be
available on IBM ftp sites (?) (URL anyone?)) or shipped
with PC DOS 7.0 and IBM's Visual Age C++ 3.5.
A copy of a Win* viewer is contained in the "Just add OS/2
Warp" package
ftp://ftp.software.ibm.com/ps/products/os2/tools/jaow/jaow.zip
in ?:\JUST_ADD\view.exe. This gives one an access to EMX's
.INF docs as well (text form is available in /emx/doc in
EMX's distribution).
Note that if you have lynx.exe installed, you can follow
WWW links from this document in .INF format. If you have
EMX docs installed correctly, you can follow library links
(you need to have `view emxbook' working by setting `EMX
BOOK' environment variable as it is described in EMX
docs).
DESCRIPTION
Target
The target is to make OS/2 the best supported platform for
using/building/developing Perl and Perl applications, as
well as make Perl the best language to use under OS/2. The
secondary target is to try to make this work under DOS and
Win* as well (but not too hard).
The current state is quite close to this target. Known
limitations:
· Some *nix programs use fork() a lot, but currently
fork() is not supported after useing dynamically
loaded extensions.
the perl__.exe manpage) to use PM code in your appli
cation (like the forthcoming Perl/Tk).
· There is no simple way to access WPS objects. The
only way I know is via `OS2::REXX' extension (see the
OS2::REXX manpage), and we do not have access to con
venience methods of Object-REXX. (Is it possible at
all? I know of no Object-REXX API.)
Please keep this list up-to-date by informing me about
other items.
Other OSes
Since OS/2 port of perl uses a remarkable EMX environment,
it can run (and build extensions, and - possibly - be
build itself) under any environment which can run EMX. The
current list is DOS, DOS-inside-OS/2, Win0.3*, Win0.95 and
WinNT. Out of many perl flavors, only one works, see the
section on "perl_.exe".
Note that not all features of Perl are available under
these environments. This depends on the features the
extender - most probably RSX - decided to implement.
Cf. the Prerequisites manpage.
Prerequisites
EMX EMX runtime is required (may be substituted by RSX).
Note that it is possible to make perl_.exe to run
under DOS without any external support by binding
emx.exe/rsx.exe to it, see the emxbind manpage. Note
that under DOS for best results one should use RSX
runtime, which has much more functions working (like
`fork', `popen' and so on). In fact RSX is required
if there is no VCPI present. Note the RSX requires
DPMI.
Only the latest runtime is supported, currently
`0.9c'. Perl may run under earlier versions of EMX,
but this is not tested.
One can get different parts of EMX from, say
ftp://ftp.cdrom.com/pub/os2/emx09c/
ftp://hobbes.nmsu.edu/os2/unix/emx09c/
The runtime component should have the name
emxrt.zip.
NOTE. It is enough to have emx.exe/rsx.exe on your
(though this
emx perl_.exe -de 0
will work as well.)
RSX To run Perl on DPMI platforms one needs RSX runtime.
This is needed under DOS-inside-OS/2, Win0.3*,
Win0.95 and WinNT (see the section on "Other OSes").
RSX would not work with VCPI only, as EMX would, it
requires DMPI.
Having RSX and the latest sh.exe one gets a fully
functional *nix-ish environment under DOS, say,
`fork', ```' and pipe-`open' work. In fact, Make
Maker works (for static build), so one can have Perl
development environment under DOS.
One can get RSX from, say
ftp://ftp.cdrom.com/pub/os2/emx09c/contrib
ftp://ftp.uni-bielefeld.de/pub/systems/msdos/misc
ftp://ftp.leo.org/pub/comp/os/os2/leo/devtools/emx+gcc/contrib
Contact the author on `rainer@mathematik.uni-biele
feld.de'.
The latest sh.exe with DOS hooks is available at
ftp://ftp.math.ohio-state.edu/pub/users/ilya/os2/sh_dos.zip
HPFS Perl does not care about file systems, but to
install the whole perl library intact one needs a
file system which supports long file names.
Note that if you do not plan to build the perl
itself, it may be possible to fool EMX to truncate
file names. This is not supported, read EMX docs to
see how to do it.
pdksh To start external programs with complicated command
lines (like with pipes in between, and/or quoting of
arguments), Perl uses an external shell. With EMX
port such shell should be named <sh.exe>, and
located either in the wired-in-during-compile loca
tions (usually F:/bin), or in configurable location
(see the section on "PERL_SH_DIR").
For best results use EMX pdksh. The soon-to-be-
available standard binary (5.2.12?) runs under DOS
(with the RSX manpage) as well, meanwhile use the
binary from
Starting Perl programs under OS/2 (and DOS and...)
Start your Perl program foo.pl with arguments `arg1 arg2
arg3' the same way as on any other platform, by
perl foo.pl arg1 arg2 arg3
If you want to specify perl options `-my_opts' to the perl
itself (as opposed to to your program), use
perl -my_opts foo.pl arg1 arg2 arg3
Alternately, if you use OS/2-ish shell, like CMD or 4os2,
put the following at the start of your perl script:
extproc perl -S -my_opts
rename your program to foo.cmd, and start it by typing
foo arg1 arg2 arg3
Note that because of stupid OS/2 limitations the full path
of the perl script is not available when you use
`extproc', thus you are forced to use `-S' perl switch,
and your script should be on path. As a plus side, if you
know a full path to your script, you may still start it
with
perl ../../blah/foo.cmd arg1 arg2 arg3
(note that the argument `-my_opts' is taken care of by the
`extproc' line in your script, see the section on
"`extproc' on the first line").
To understand what the above magic does, read perl docs
about `-S' switch - see the perlrun manpage, and cmdref
about `extproc':
view perl perlrun
man perlrun
view cmdref extproc
help extproc
or whatever method you prefer.
There are also endless possibilities to use executable
extensions of 4os2, associations of WPS and so on... How
ever, if you use *nixish shell (like sh.exe supplied in
the binary distribution), you need to follow the syntax
specified in the Switches entry in the perlrun manpage.
extensions .cmd, .btm, .bat, .pl as well.
Starting OS/2 (and DOS) programs under Perl
This is what system() (see the system entry in the perl
func manpage), ```' (see the I/O Operators entry in the
perlop manpage), and open pipe (see the open entry in the
perlfunc manpage) are for. (Avoid exec() (see the exec
entry in the perlfunc manpage) unless you know what you
do).
Note however that to use some of these operators you need
to have a sh-syntax shell installed (see the section on
"Pdksh", the section on "Frequently asked questions"), and
perl should be able to find it (see the section on
"PERL_SH_DIR").
The cases when the shell is used are:
1 One-argument system() (see the system entry in the
perlfunc manpage), exec() (see the exec entry in the
perlfunc manpage) with redirection or shell meta-char
acters;
2 Pipe-open (see the open entry in the perlfunc manpage)
with the command which contains redirection or shell
meta-characters;
3 Backticks ```' (see the I/O Operators entry in the
perlop manpage) with the command which contains redi
rection or shell meta-characters;
4 If the executable called by system()/exec()/pipe-
open()/```' is a script with the "magic" `#!' line or
`extproc' line which specifies shell;
5 If the executable called by system()/exec()/pipe-
open()/```' is a script without "magic" line, and
`$ENV{EXECSHELL}' is set to shell;
6 If the executable called by system()/exec()/pipe-
open()/```' is not found;
7 For globbing (see the glob entry in the perlfunc man
page, the I/O Operators entry in the perlop manpage).
For the sake of speed for a common case, in the above
algorithms backslashes in the command name are not consid
ered as shell metacharacters.
Perl starts scripts which begin with cookies `extproc' or
`#!' directly, without an intervention of shell. Perl
uses the same algorithm to find the executable as pdksh:
then the executable is searched in . and on `PATH'. To
find arguments for these scripts Perl uses a different
algorithm than pdksh: up to 3 arguments are recognized,
and trailing whitespace is stripped.
If a script does not contain such a cooky, then to avoid
calling sh.exe, Perl uses the same algorithm as pdksh: if
`$ENV{EXECSHELL}' is set, the script is given as the first
argument to this command, if not set, then `$ENV{COMSPEC}
/c' is used (or a hardwired guess if `$ENV{COMSPEC}' is
not set).
If starting scripts directly, Perl will use exactly the
same algorithm as for the search of script given by -S
command-line option: it will look in the current direc
tory, then on components of `$ENV{PATH}' using the follow
ing order of appended extensions: no extension, .cmd,
.btm, .bat, .pl.
Note that Perl will start to look for scripts only if OS/2
cannot start the specified application, thus `system
'blah'' will not look for a script if there is an exe
cutable file blah.exe anywhere on `PATH'.
Note also that executable files on OS/2 can have an arbi
trary extension, but .exe will be automatically appended
if no dot is present in the name. The workaround as as
simple as that: since blah. and blah denote the same
file, to start an executable residing in file n:/bin/blah
(no extension) give an argument `n:/bin/blah.' to sys
tem().
The last note is that currently it is not straightforward
to start PM programs from VIO (=text-mode) Perl process
and visa versa. Either ensure that shell will be used, as
in `system 'cmd /c epm'', or start it using optional argu
ments to system() documented in `OS2::Process' module.
This is considered a bug and should be fixed soon.
Frequently asked questions
I cannot run external programs
Did you run your programs with `-w' switch? See the 2
(and DOS) programs under Perl entry in the Starting OS
manpage.
Do you try to run internal shell commands, like ``copy
a b`' (internal for cmd.exe), or ``glob a*b`' (inter
nal for ksh)? You need to specify your shell explic
itly, like ``cmd /c copy a b`', since Perl cannot
deduce which commands are internal to your shell.
my
program." program."
Is your program EMX-compiled with `-Zmt -Zcrtdll'?
If not, you need to build a stand-alone DLL for perl.
Contact me, I did it once. Sockets would not work, as
a lot of other stuff.
Did you use the ExtUtils::Embed manpage?
I had reports it does not work. Somebody would need to
fix it.
```' and pipe-`open' do not work under DOS.
This may a variant of just the section on "I cannot run
external programs", or a deeper problem. Basically: you
need RSX (see the section on "Prerequisites") for these
commands to work, and you may need a port of sh.exe which
understands command arguments. One of such ports is listed
in the section on "Prerequisites" under RSX. Do not forget
to set variable `the section on "PERL_SH_DIR"' as well.
DPMI is required for RSX.
Cannot start `find.exe "pattern" file'
Use one of
system 'cmd', '/c', 'find "pattern" file';
`cmd /c 'find "pattern" file'`
This would start find.exe via cmd.exe via `sh.exe' via
`perl.exe', but this is a price to pay if you want to use
non-conforming program. In fact find.exe cannot be started
at all using C library API only. Otherwise the following
command-lines were equivalent:
find "pattern" file
find pattern file
INSTALLATION
Automatic binary installation
The most convenient way of installing perl is via perl
installer install.exe. Just follow the instructions, and
99% of the installation blues would go away.
Note however, that you need to have unzip.exe on your
path, and EMX environment running. The latter means that
if you just installed EMX, and made all the needed changes
to Config.sys, you may need to reboot in between. Check
emxrev
A folder is created on your desktop which contains some
useful objects.
Things not taken care of by automatic binary installation:
`PERL_BADLANG' may be needed if you change your codepage
after perl installation, and the new value
is not supported by EMX. See the section on
"PERL_BADLANG".
`PERL_BADFREE' see the section on "PERL_BADFREE".
Config.pm This file resides somewhere deep in the
location you installed your perl library,
find it out by
perl -MConfig -le "print $INC{'Config.pm'}"
While most important values in this file
are updated by the binary installer, some
of them may need to be hand-edited. I know
no such data, please keep me informed if
you find one.
NOTE. Because of a typo the binary installer of 5.00305
would install a variable `PERL_SHPATH' into Config.sys.
Please remove this variable and put `the PERL_SH_DIR man
page' instead.
Manual binary installation
As of version 5.00305, OS/2 perl binary distribution comes
split into 11 components. Unfortunately, to enable config
urable binary installation, the file paths in the zip
files are not absolute, but relative to some directory.
Note that the extraction with the stored paths is still
necessary (default with unzip, specify `-d' to pkunzip).
However, you need to know where to extract the files. You
need also to manually change entries in Config.sys to
reflect where did you put the files. Note that if you have
some primitive unzipper (like pkunzip), you may get a lot
of warnings/errors during unzipping. Upgrade to
`(w)unzip'.
Below is the sample of what to do to reproduce the config
uration on my machine:
Perl VIO and PM executables (dynamically linked)
unzip perl_exc.zip *.dll -d f:/emx.add/dll
(have the directories with `*.exe' on PATH, and `*.dll'
on LIBPATH);
Perl_ VIO executable (statically linked)
unzip perl_aou.zip -d f:/emx.add/bin
(have the directory on PATH);
Executables for Perl utilities
unzip perl_utl.zip -d f:/emx.add/bin
(have the directory on PATH);
Main Perl library
unzip perl_mlb.zip -d f:/perllib/lib
If this directory is preserved, you do not need to
change anything. However, for perl to find it if it is
changed, you need to `set PERLLIB_PREFIX' in Con
fig.sys, see the section on "PERLLIB_PREFIX".
Additional Perl modules
unzip perl_ste.zip -d f:/perllib/lib/site_perl
If you do not change this directory, do nothing. Other
wise put this directory and subdirectory ./os2 in `PER
LLIB' or `PERL5LIB' variable. Do not use `PERL5LIB'
unless you have it set already. See the ENVIRONMENT
entry in the perl manpage.
Tools to compile Perl modules
unzip perl_blb.zip -d f:/perllib/lib
If this directory is preserved, you do not need to
change anything. However, for perl to find it if it is
changed, you need to `set PERLLIB_PREFIX' in Con
fig.sys, see the section on "PERLLIB_PREFIX".
Manpages for Perl and utilities
unzip perl_man.zip -d f:/perllib/man
This directory should better be on `MANPATH'. You need
to have a working man to access these files.
Manpages for Perl modules
unzip perl_mam.zip -d f:/perllib/man
This directory should better be on `MANPATH'. You need
to have a working man to access these files.
unzip perl_pod.zip -d f:/perllib/lib
This is used by by `perldoc' program (see the perldoc
manpage), and may be used to generate HTML documenta
tion usable by WWW browsers, and documentation in zil
lions of other formats: `info', `LaTeX', `Acrobat',
`FrameMaker' and so on.
Perl manual in .INF format
unzip perl_inf.zip -d d:/os2/book
This directory should better be on `BOOKSHELF'.
Pdksh
unzip perl_sh.zip -d f:/bin
This is used by perl to run external commands which
explicitly require shell, like the commands using redi
rection and shell metacharacters. It is also used
instead of explicit /bin/sh.
Set `PERL_SH_DIR' (see the section on "PERL_SH_DIR") if
you move sh.exe from the above location.
Note. It may be possible to use some other sh-compati
ble shell (not tested).
After you installed the components you needed and updated
the Config.sys correspondingly, you need to hand-edit Con
fig.pm. This file resides somewhere deep in the location
you installed your perl library, find it out by
perl -MConfig -le "print $INC{'Config.pm'}"
You need to correct all the entries which look like file
paths (they currently start with `f:/').
Warning
The automatic and manual perl installation leave precom
piled paths inside perl executables. While these paths are
overwriteable (see the section on "PERLLIB_PREFIX", the
section on "PERL_SH_DIR"), one may get better results by
binary editing of paths inside the executables/DLLs.
Accessing documentation
Depending on how you built/installed perl you may have
(otherwise identical) Perl documentation in the following
formats:
Most probably the most convenient form. Under OS/2 view it
as
view perl
view perl perlfunc
view perl less
view perl ExtUtils::MakeMaker
(currently the last two may hit a wrong location, but this
may improve soon). Under Win* see the section on "SYNOP
SIS".
If you want to build the docs yourself, and have OS/2
toolkit, run
pod2ipf > perl.ipf
in /perllib/lib/pod directory, then
ipfc /inf perl.ipf
(Expect a lot of errors during the both steps.) Now move
it on your BOOKSHELF path.
Plain text
If you have perl documentation in the source form, perl
utilities installed, and GNU groff installed, you may use
perldoc perlfunc
perldoc less
perldoc ExtUtils::MakeMaker
to access the perl documentation in the text form (note
that you may get better results using perl manpages).
Alternately, try running pod2text on .pod files.
Manpages
If you have man installed on your system, and you
installed perl manpages, use something like this:
man perlfunc
man 3 less
man ExtUtils.MakeMaker
to access documentation for different components of Perl.
Start with
man perl
mentation for packages, and as usual, sometimes you need
to give the section - `3' above - to avoid shadowing by
the less(1) manpage.
Make sure that the directory above the directory with man
pages is on our `MANPATH', like this
set MANPATH=c:/man;f:/perllib/man
HTML
If you have some WWW browser available, installed the Perl
documentation in the source form, and Perl utilities, you
can build HTML docs. Cd to directory with .pod files, and
do like this
cd f:/perllib/lib/pod
pod2html
After this you can direct your browser the file perl.html
in this directory, and go ahead with reading docs, like
this:
explore file:///f:/perllib/lib/pod/perl.html
Alternatively you may be able to get these docs prebuilt
from CPAN.
GNU `info' files
Users of Emacs would appreciate it very much, especially
with `CPerl' mode loaded. You need to get latest
`pod2info' from `CPAN', or, alternately, prebuilt info
pages.
for `Acrobat' are available on CPAN (for slightly old ver
sion of perl).
`LaTeX' docs
can be constructed using `pod2latex'.
BUILD
Here we discuss how to build Perl under OS/2. There is an
alternative (but maybe older) view on the section on
"/www.shadow.net/~troc/os2perl.html" in the http: manpage.
Prerequisites
You need to have the latest EMX development environment,
the full GNU tool suite (gawk renamed to awk, and GNU
sort.exe, to check use
find --version
sort --version
). You need the latest version of pdksh installed as
sh.exe.
Check that you have BSD libraries and headers installed,
and - optionally - Berkeley DB headers and libraries, and
crypt.
Possible locations to get this from are
ftp://hobbes.nmsu.edu/os2/unix/
ftp://ftp.cdrom.com/pub/os2/unix/
ftp://ftp.cdrom.com/pub/os2/dev32/
ftp://ftp.cdrom.com/pub/os2/emx09c/
It is reported that the following archives contain enough
utils to build perl: gnufutil.zip, gnusutil.zip, gnutu
til.zip, gnused.zip, gnupatch.zip, gnuawk.zip, gnumake.zip
and ksh527rt.zip. Note that all these utilities are known
to be available from LEO:
ftp://ftp.leo.org/pub/comp/os/os2/leo/gnu
Make sure that no copies or perl are currently running.
Later steps of the build may fail since an older version
of perl.dll loaded into memory may be found.
Also make sure that you have /tmp directory on the current
drive, and . directory in your `LIBPATH'. One may try to
correct the latter condition by
set BEGINLIBPATH .
if you use something like CMD.EXE or latest versions of
4os2.exe.
Make sure your gcc is good for `-Zomf' linking: run
`omflibs' script in /emx/lib directory.
Check that you have link386 installed. It comes standard
with OS/2, but may be not installed due to customization.
If typing
link386
shows you do not have it, do Selective install, and choose
`Link object modules' in Optional system utilities/More.
If you get into link386, press `Ctrl-C'.
You need to fetch the latest perl source (including devel
opers releases). With some probability it is located in
http://www.perl.com/CPAN/src/5.0
http://www.perl.com/CPAN/src/5.0/unsupported
If not, you may need to dig in the indices to find it in
the directory of the current maintainer.
Quick cycle of developers release may break the OS/2 build
time to time, looking into
http://www.perl.com/CPAN/ports/os2/ilyaz/
may indicate the latest release which was publicly
released by the maintainer. Note that the release may
include some additional patches to apply to the current
source of perl.
Extract it like this
tar vzxf perl5.00409.tar.gz
You may see a message about errors while extracting Con
figure. This is because there is a conflict with a simi
larly-named file configure.
Change to the directory of extraction.
Application of the patches
You need to apply the patches in ./os2/diff.* like this:
gnupatch -p0 < os2\diff.configure
You may also need to apply the patches supplied with the
binary distribution of perl.
Note also that the db.lib and db.a from the EMX distribu
tion are not suitable for multi-threaded compile (note
that currently perl is not multithread-safe, but is com
piled as multithreaded for compatibility with
XFree86-OS/2). Get a corrected one from
ftp://ftp.math.ohio-state.edu/pub/users/ilya/os2/db_mt.zip
To make `-p' filetest work, one may also need to apply the
following patch to EMX headers:
+++ /emx/include/sys/stat.h Sun Jul 12 14:11:32 1998
@@ -53,7 +53,7 @@ struct stat
#endif
#if !defined (S_IFMT)
-#define S_IFMT 0160000 /* Mask for file type */
+#define S_IFMT 0170000 /* Mask for file type */
#define S_IFIFO 0010000 /* Pipe */
#define S_IFCHR 0020000 /* Character device */
#define S_IFDIR 0040000 /* Directory */
Hand-editing
You may look into the file ./hints/os2.sh and correct any
thing wrong you find there. I do not expect it is needed
anywhere.
Making
sh Configure -des -D prefix=f:/perllib
`prefix' means: where to install the resulting perl
library. Giving correct prefix you may avoid the need to
specify `PERLLIB_PREFIX', see the section on "PERLLIB_PRE
FIX".
Ignore the message about missing `ln', and about `-c'
option to tr. In fact if you can trace where the latter
spurious warning comes from, please inform me.
Now
make
At some moment the built may die, reporting a version mis
match or unable to run perl. This means that most of the
build has been finished, and it is the time to move the
constructed perl.dll to some absolute location in LIBPATH.
After this is done the build should finish without a lot
of fuss. One can avoid the interruption if one has the
correct prebuilt version of perl.dll on LIBPATH, but prob
ably this is not needed anymore, since miniperl.exe is
linked statically now.
Warnings which are safe to ignore: mkfifo() redefined
inside POSIX.c.
Testing
If you haven't yet moved perl.dll onto LIBPATH, do it now
(alternatively, if you have a previous perl installation
you'd rather not disrupt until this one is installed, copy
Now run
make test
All tests should succeed (with some of them skipped).
Note that on one of the systems I see intermittent fail
ures of io/pipe.t subtest 9. Any help to track what hap
pens with this test is appreciated.
Some tests may generate extra messages similar to
A lot of `bad free'
in database tests related to Berkeley DB. This is a
confirmed bug of DB. You may disable this warnings,
see the section on "PERL_BADFREE".
There is not much we can do with it (but apparently it
does not cause any real error with data).
Process terminated by SIGTERM/SIGINT
This is a standard message issued by OS/2 applica
tions. *nix applications die in silence. It is consid
ered a feature. One can easily disable this by appro
priate sighandlers.
However the test engine bleeds these message to screen
in unexpected moments. Two messages of this kind
should be present during testing.
Two lib/io_* tests may generate popups (system error
`SYS3175'), but should succeed anyway. This is due to a
bug of EMX related to fork()ing with dynamically loaded
libraries.
I submitted a patch to EMX which makes it possible to
fork() with EMX dynamic libraries loaded, which makes
lib/io* tests pass without skipping offended tests. This
means that soon the number of skipped tests may decrease
yet more.
To get finer test reports, call
perl t/harness
The report with io/pipe.t failing may look like this:
Failed Test Status Wstat Total Fail Failed List of failed
------------------------------------------------------------
io/pipe.t 12 1 8.33% 9
7 tests skipped, plus 56 subtests skipped.
Failed 1/195 test scripts, 99.49% okay. 1/6542 subtests failed, 99.98% okay.
op/fs.t
18 Checks `atime' and `mtime' of `stat()' -
unfortunately, HPFS provides only 2sec time
granularity (for compatibility with FAT?).
25 Checks `truncate()' on a filehandle just
opened for write - I do not know why this
should or should not work.
lib/io_pipe.t
Checks `IO::Pipe' module. Some feature of EMX -
test fork()s with dynamic extension loaded -
unsupported now.
lib/io_sock.t
Checks `IO::Socket' module. Some feature of EMX -
test fork()s with dynamic extension loaded -
unsupported now.
op/stat.t
Checks `stat()'. Tests:
4 Checks `atime' and `mtime' of `stat()' -
unfortunately, HPFS provides only 2sec time
granularity (for compatibility with FAT?).
lib/io_udp.t
It never terminates, apparently some bug in stor
ing the last socket from which we obtained a mes
sage.
Installing the built perl
If you haven't yet moved perl.dll onto LIBPATH, do it now.
Run
make install
It would put the generated files into needed locations.
Manually put perl.exe, perl__.exe and perl___.exe to a
location on your PATH, perl.dll to a location on your LIB
PATH.
Run
make cmdscripts INSTALLCMDDIR=d:/ir/on/path
to convert perl utilities to .cmd files and put them on
PATH. You need to put .EXE-utilities on path manually.
They are installed in `$prefix/bin', here `$prefix' is
`a.out'-style build
Proceed as above, but make perl_.exe (see the section on
"perl_.exe") by
make perl_
test and install by
make aout_test
make aout_install
Manually put perl_.exe to a location on your PATH.
Since `perl_' has the extensions prebuilt, it does not
suffer from the dynamic extensions + fork() syndrome, thus
the failing tests look like
Failed Test Status Wstat Total Fail Failed List of failed
---------------------------------------------------------------
io/fs.t 26 11 42.31% 2-5, 7-11, 18, 25
op/stat.t 56 5 8.93% 3-4, 20, 35, 39
Failed 2/118 test scripts, 98.31% okay. 16/2445 subtests failed, 99.35% okay.
Note. The build process for `perl_' does not know about
all the dependencies, so you should make sure that any
thing is up-to-date, say, by doing
make perl.dll
first.
Build FAQ
Some `/' became `\' in pdksh.
You have a very old pdksh. See the Prerequisites manpage.
`'errno'' - unresolved external
You do not have MT-safe db.lib. See the Prerequisites man
page.
Problems with tr or sed
reported with very old version of tr and sed.
Some problem (forget which ;-)
You have an older version of perl.dll on your LIBPATH,
which broke the build of extensions.
You did not run `omflibs'. See the Prerequisites manpage.
Segfault in make
You use an old version of GNU make. See the Prerequisites
manpage.
Specific (mis)features of OS/2 port
`setpriority', `getpriority'
Note that these functions are compatible with *nix, not
with the older ports of '94 - 95. The priorities are abso
lute, go from 32 to -95, lower is quicker. 0 is the
default priority.
`system()'
Multi-argument form of `system()' allows an additional
numeric argument. The meaning of this argument is
described in the OS2::Process manpage.
`extproc' on the first line
If the first chars of a script are `"extproc "', this line
is treated as `#!'-line, thus all the switches on this
line are processed (twice if script was started via
cmd.exe).
Additional modules:
the OS2::Process manpage, the OS2::REXX manpage, the
OS2::PrfDB manpage, the OS2::ExtAttr manpage. These mod
ules provide access to additional numeric argument for
`system' and to the list of the running processes, to DLLs
having functions with REXX signature and to REXX runtime,
to OS/2 databases in the .INI format, and to Extended
Attributes.
Two additional extensions by Andreas Kaiser, `OS2::UPM',
and `OS2::FTP', are included into my ftp directory, mir
rored on CPAN.
Prebuilt methods:
`File::Copy::syscopy'
used by `File::Copy::copy', see the File::Copy man
page.
`DynaLoader::mod2fname'
used by `DynaLoader' for DLL name mangling.
Self explanatory.
`Cwd::sys_chdir(name)'
leaves drive as it is.
`Cwd::change_drive(name)'
`Cwd::sys_is_absolute(name)'
means has drive letter and is_rooted.
`Cwd::sys_is_rooted(name)'
means has leading `[/\\]' (maybe after a drive-let
ter:).
`Cwd::sys_is_relative(name)'
means changes with current dir.
`Cwd::sys_cwd(name)'
Interface to cwd from EMX. Used by `Cwd::cwd'.
`Cwd::sys_abspath(name, dir)'
Really really odious function to implement. Returns
absolute name of file which would have `name' if CWD
were `dir'. `Dir' defaults to the current dir.
`Cwd::extLibpath([type])'
Get current value of extended library search path. If
`type' is present and true, works with END_LIBPATH,
otherwise with `BEGIN_LIBPATH'.
`Cwd::extLibpath_set( path [, type ] )'
Set current value of extended library search path. If
`type' is present and true, works with END_LIBPATH,
otherwise with `BEGIN_LIBPATH'.
(Note that some of these may be moved to different
libraries - eventually).
Misfeatures
Since flock(3) is present in EMX, but is not func
tional, it is emulated by perl. To disable the emula
tions, set environment variable `USE_PERL_FLOCK=0'.
Here is the list of things which may be "broken" on
EMX (from EMX docs):
· The functions recvmsg(3), sendmsg(3), and
socketpair(3) are not implemented.
· sock_init(3) is not required and not implemented.
(Perl has a workaround.)
· kill(3): Special treatment of PID=0, PID=1 and
PID=-1 is not implemented.
· waitpid(3):
WUNTRACED
Not implemented.
waitpid() is not implemented for negative values of PID.
Note that `kill -9' does not work with the current
version of EMX.
Since sh.exe is used for globing (see the glob entry
in the perlfunc manpage), the bugs of sh.exe plague
perl as well.
In particular, uppercase letters do not work in
`[...]'-patterns with the current pdksh.
Modifications
Perl modifies some standard C library calls in the follow
ing ways:
`popen' `my_popen' uses sh.exe if shell is required, cf.
the section on "PERL_SH_DIR".
`tmpnam' is created using `TMP' or `TEMP' environment
variable, via `tempnam'.
`tmpfile'
If the current directory is not writable, file is
created using modified `tmpnam', so there may be
a race condition.
`ctermid'
a dummy implementation.
`stat' `os2_stat' special-cases /dev/tty and /dev/con.
`flock' Since flock(3) is present in EMX, but is not
functional, it is emulated by perl. To disable
the emulations, set environment variable
`USE_PERL_FLOCK=0'.
Perl flavors
Because of idiosyncrasies of OS/2 one cannot have all the
eggs in the same basket (though EMX environment tries hard
to overcome this limitations, so the situation may somehow
improve). There are 4 executables for Perl provided by the
perl.exe
The main workhorse. This is a chimera executable: it is
compiled as an `a.out'-style executable, but is linked
with `omf'-style dynamic library perl.dll, and with
dynamic CRT DLL. This executable is a VIO application.
It can load perl dynamic extensions, and it can fork().
Unfortunately, with the current version of EMX it cannot
fork() with dynamic extensions loaded (may be fixed by
patches to EMX).
Note. Keep in mind that fork() is needed to open a pipe to
yourself.
perl_.exe
This is a statically linked `a.out'-style executable. It
can fork(), but cannot load dynamic Perl extensions. The
supplied executable has a lot of extensions prebuilt, thus
there are situations when it can perform tasks not possi
ble using perl.exe, like fork()ing when having some stan
dard extension loaded. This executable is a VIO applica
tion.
Note. A better behaviour could be obtained from `perl.exe'
if it were statically linked with standard Perl exten
sions, but dynamically linked with the Perl DLL and CRT
DLL. Then it would be able to fork() with standard exten
sions, and would be able to dynamically load arbitrary
extensions. Some changes to Makefiles and hint files
should be necessary to achieve this.
This is also the only executable with does not require
OS/2. The friends locked into `M$' world would appreciate
the fact that this executable runs under DOS, Win0.3*,
Win0.95 and WinNT with an appropriate extender. See the
section on "Other OSes".
perl__.exe
This is the same executable as perl___.exe, but it is a PM
application.
Note. Usually STDIN, STDERR, and STDOUT of a PM applica
tion are redirected to `nul'. However, it is possible to
see them if you start `perl__.exe' from a PM program which
emulates a console window, like Shell mode of Emacs or
EPM. Thus it is possible to use Perl debugger (see the
perldebug manpage) to debug your PM application.
This flavor is required if you load extensions which use
perl___.exe
This is an `omf'-style executable which is dynamically
linked to perl.dll and CRT DLL. I know no advantages of
this executable over `perl.exe', but it cannot fork() at
all. Well, one advantage is that the build process is not
so convoluted as with `perl.exe'.
It is a VIO application.
Why strange names?
Since Perl processes the `#!'-line (cf. the DESCRIPTION
entry in the perlrun manpage, the Switches entry in the
perlrun manpage, the Not a perl script entry in the perl
diag manpage, the No Perl script found in input entry in
the perldiag manpage), it should know when a program is a
Perl. There is some naming convention which allows Perl to
distinguish correct lines from wrong ones. The above names
are almost the only names allowed by this convention which
do not contain digits (which have absolutely different
semantics).
Why dynamic linking?
Well, having several executables dynamically linked to the
same huge library has its advantages, but this would not
substantiate the additional work to make it compile. The
reason is stupid-but-quick "hard" dynamic linking used by
OS/2.
The address tables of DLLs are patched only once, when
they are loaded. The addresses of entry points into DLLs
are guaranteed to be the same for all programs which use
the same DLL, which reduces the amount of runtime patching
- once DLL is loaded, its code is read-only.
While this allows some performance advantages, this makes
life terrible for developers, since the above scheme makes
it impossible for a DLL to be resolved to a symbol in the
.EXE file, since this would need a DLL to have different
relocations tables for the executables which use it.
However, a Perl extension is forced to use some symbols
from the perl executable, say to know how to find the
arguments provided on the perl internal evaluation stack.
The solution is that the main code of interpreter should
be contained in a DLL, and the .EXE file just loads this
DLL into memory and supplies command-arguments.
This greatly increases the load time for the application
(as well as the number of problems during compilation).
to reside in a DLL as well (otherwise extensions would not
be able to use CRT).
Why chimera build?
Current EMX environment does not allow DLLs compiled using
Unixish `a.out' format to export symbols for data. This
forces `omf'-style compile of perl.dll.
Current EMX environment does not allow .EXE files compiled
in `omf' format to fork(). fork() is needed for exactly
three Perl operations:
explicit fork()
in the script, and
open FH, ""|-""
open FH, ""-|""
opening pipes to itself.
While these operations are not questions of life and
death, a lot of useful scripts use them. This forces
`a.out'-style compile of perl.exe.
ENVIRONMENT
Here we list environment variables with are either OS/2-
and DOS- and Win*-specific, or are more important under
OS/2 than under other OSes.
`PERLLIB_PREFIX'
Specific for EMX port. Should have the form
path1;path2
or
path1 path2
If the beginning of some prebuilt path matches path1, it
is substituted with path2.
Should be used if the perl library is moved from the
default location in preference to `PERL(5)LIB', since this
would not leave wrong entries in @INC. Say, if the com
piled version of perl looks for @INC in f:/perllib/lib,
and you want to install the library in h:/opt/gnu, do
set PERLLIB_PREFIX=f:/perllib/lib;h:/opt/gnu
If 1, perl ignores setlocale() failing. May be useful with
some strange locales.
`PERL_BADFREE'
If 1, perl would not warn of in case of unwarranted
free(). May be useful in conjunction with the module
DB_File, since Berkeley DB memory handling code is buggy.
`PERL_SH_DIR'
Specific for EMX port. Gives the directory part of the
location for sh.exe.
`USE_PERL_FLOCK'
Specific for EMX port. Since flock(3) is present in EMX,
but is not functional, it is emulated by perl. To disable
the emulations, set environment variable
`USE_PERL_FLOCK=0'.
`TMP' or `TEMP'
Specific for EMX port. Used as storage place for temporary
files, most notably `-e' scripts.
Evolution
Here we list major changes which could make you by sur
prise.
Priorities
`setpriority' and `getpriority' are not compatible with
earlier ports by Andreas Kaiser. See `"setpriority, get
priority"'.
DLL name mangling
With the release 5.003_01 the dynamically loadable
libraries should be rebuilt. In particular, DLLs are now
created with the names which contain a checksum, thus
allowing workaround for OS/2 scheme of caching DLLs.
Threading
As of release 5.003_01 perl is linked to multithreaded CRT
DLL. If perl itself is not compiled multithread-enabled,
so will not be perl malloc(). However, extensions may use
multiple thread on their own risk.
Needed to compile `Perl/Tk' for XFree86-OS/2 out-of-the-
box.
Due to a popular demand the perl external program calling
has been changed wrt Andreas Kaiser's port. If perl needs
to call an external program via shell, the f:/bin/sh.exe
will be called, or whatever is the override, see the sec
tion on "PERL_SH_DIR".
Thus means that you need to get some copy of a sh.exe as
well (I use one from pdksh). The drive F: above is set up
automatically during the build to a correct value on the
builder machine, but is overridable at runtime,
Reasons: a consensus on `perl5-porters' was that perl
should use one non-overridable shell per platform. The
obvious choices for OS/2 are cmd.exe and sh.exe. Having
perl build itself would be impossible with cmd.exe as a
shell, thus I picked up `sh.exe'. Thus assures almost 100%
compatibility with the scripts coming from *nix. As an
added benefit this works as well under DOS if you use DOS-
enabled port of pdksh (see the section on "Prerequi
sites").
Disadvantages: currently sh.exe of pdksh calls external
programs via fork()/exec(), and there is no functioning
exec() on OS/2. exec() is emulated by EMX by asyncroneous
call while the caller waits for child completion (to pre
tend that the `pid' did not change). This means that 1
extra copy of sh.exe is made active via fork()/exec(),
which may lead to some resources taken from the system
(even if we do not count extra work needed for fork()ing).
Note that this a lesser issue now when we do not spawn
sh.exe unless needed (metachars found).
One can always start cmd.exe explicitly via
system 'cmd', '/c', 'mycmd', 'arg1', 'arg2', ...
If you need to use cmd.exe, and do not want to hand-edit
thousands of your scripts, the long-term solution proposed
on p5-p is to have a directive
use OS2::Cmd;
which will override system(), exec(), ```', and
`open(,'...|')'. With current perl you may override only
system(), readpipe() - the explicit version of ```', and
maybe exec(). The code will substitute the one-argument
call to system() by `CORE::system('cmd.exe', '/c',
shift)'.
If you have some working code for `OS2::Cmd', please send
it to me, I will include it into distribution. I have no
For the details of the current situation with calling
external programs, see the 2 (and DOS) programs under Perl
entry in the Starting OS manpage.
External scripts may be called by name. Perl will try
the same extensions as when processing -S command-line
switch.
Memory allocation
Perl uses its own malloc() under OS/2 - interpreters are
usually malloc-bound for speed, but perl is not, since its
malloc is lightning-fast. Perl-memory-usage-tuned bench
marks show that Perl's malloc is 5 times quickier than EMX
one. I do not have convincing data about memory foot
pring, but a (pretty random) benchmark showed that Perl
one is 5% better.
Combination of perl's malloc() and rigid DLL name resolu
tion creates a special problem with library functions
which expect their return value to be free()d by system's
free(). To facilitate extensions which need to call such
functions, system memory-allocation functions are still
available with the prefix `emx_' added. (Currently only
DLL perl has this, it should propagate to perl_.exe
shortly.)
Threads
One can build perl with thread support enabled by provid
ing `-D usethreads' option to Configure. Currently OS/2
support of threads is very preliminary.
Most notable problems:
`COND_WAIT'
may have a race condition. Needs a reimplementation
(in terms of chaining waiting threads, with linker
list stored in per-thread structure?).
os2.c
has a couple of static variables used in OS/2-specific
functions. (Need to be moved to per-thread structure,
or serialized?)
Note that these problems should not discourage experiment
ing, since they have a low probability of affecting small
programs.
AUTHOR
Ilya Zakharevich, ilya@math.ohio-state.edu
perl(1).
Man(1) output converted with
man2html