=head1 NAME
-perlos2 - Perl under OS/2, Win0.31, Win0.95 and WinNT.
+perlos2 - Perl under OS/2, DOS, Win0.3*, Win0.95 and WinNT.
=head1 SYNOPSIS
to list some (not all may be available simultaneously), or it may
be read I<as is>: either as F<README.os2>, or F<pod/perlos2.pod>.
+To read the F<.INF> version of documentation (B<very> recommended)
+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.
+
=cut
Contents
- Starting Perl programs under OS/2
- Starting OS/2 programs under Perl
Frequently asked questions
- - I cannot run extenal programs
+ - I cannot run external programs
- I cannot embed perl into my program, or use perl.dll from my program.
INSTALLATION
- Automatic binary installation
- TMP or TEMP
Evolution
- Priorities
- - DLL name mungling
+ - DLL name mangling
- Threading
- Calls to external programs
AUTHOR
=head2 Target
The target is to make OS/2 the best supported platform for
-using/building/developping Perl and I<Perl applications>, as well as
+using/building/developing Perl and I<Perl applications>, as well as
make Perl the best language to use under OS/2.
The current state is quite close to this target. Known limitations:
There is no simple way to access B<WPS> objects. The only way I know
is via C<OS2::REXX> extension (see L<OS2::REXX>), and we do not have access to
-convinience methods of B<Object REXX>. (Is it possible at all? I know
+convenience methods of B<Object REXX>. (Is it possible at all? I know
of no B<Object-REXX> API.)
=back
Since OS/2 port of perl uses a remarkable B<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, Win0.31, Win0.95 and WinNT. Out of many perl flavors,
+DOS-inside-OS/2, Win0.3*, Win0.95 and WinNT. Out of many perl flavors,
only one works, see L<"perl_.exe">.
Note that not all features of Perl are available under these
=item B<EMX>
-B<EMX> runtime is required. Note that it is possible to make F<perl_.exe>
-to run under DOS without any external support by binding F<emx.exe> to
-it, see L<emxbind>.
+B<EMX> runtime is required (may be substituted by B<RSX>). Note that
+it is possible to make F<perl_.exe> to run under DOS without any
+external support by binding F<emx.exe>/F<rsx.exe> to it, see L<emxbind>. Note
+that under DOS for best results one should use B<RSX> runtime, which
+has much more functions working (like C<fork>, C<popen> and so on). In
+fact B<RSX> is required if there is no C<VCPI> present. Note the
+B<RSX> requires C<DPMI>.
Only the latest runtime is supported, currently C<0.9c>.
The runtime component should have the name F<emxrt.zip>.
+B<NOTE>. It is enough to have F<emx.exe>/F<rsx.exe> on your path. One
+does not need to specify them explicitly (though this
+
+ emx perl_.exe -de 0
+
+will work as well.)
+
=item B<RSX>
-To run Perl on C<DPMS> platforms one needs B<RSX> runtime. This is
-needed under DOS-inside-OS/2, Win0.31, Win0.95 and WinNT (see
-L<"Other OSes">).
+To run Perl on C<DPMI> platforms one needs B<RSX> runtime. This is
+needed under DOS-inside-OS/2, Win0.3*, Win0.95 and WinNT (see
+L<"Other OSes">). B<RSX> would not work with C<VCPI>
+only, as B<EMX> would, it requires C<DMPI>.
+
+Having B<RSX> and the latest F<sh.exe> one gets a fully functional
+B<*nix>-ish environment under DOS, say, C<fork>, C<``> and
+pipe-C<open> work. In fact, MakeMaker works (for static build), so one
+can have Perl development environment under DOS.
One can get B<RSX> from, say
Contact the author on C<rainer@mathematik.uni-bielefeld.de>.
+The latest F<sh.exe> with DOS hooks is available at
+
+ ftp://ftp.math.ohio-state.edu/pub/users/ilya/os2/sh_dos.exe
+
=item B<HPFS>
Perl does not care about file systems, but to install the whole perl
or whatever method you prefer.
-There are also endless possibilites to use I<executable extensions> of
+There are also endless possibilities to use I<executable extensions> of
B<4OS2>, I<associations> of B<WPS> and so on... However, if you use
*nixish shell (like F<sh.exe> supplied in the binary distribution),
-you need follow the syntax specified in L<perlrun/"Switches">.
+you need to follow the syntax specified in L<perlrun/"Switches">.
=head2 Starting OS/2 programs under Perl
=head1 Frequently asked questions
-=head2 I cannot run extenal programs
+=head2 I cannot run external programs
+
+=over 4
+
+=item
Did you run your programs with C<-w> switch? See
L<Starting OS/2 programs under Perl>.
+=item
+
+Do you try to run I<internal> shell commands, like C<`copy a b`>
+(internal for F<cmd.exe>), or C<`glob a*b`> (internal for ksh)? You
+need to specify your shell explicitly, like C<`cmd /c copy a b`>,
+since Perl cannot deduce which commands are internal to your shell.
+
+=back
+
=head2 I cannot embed perl into my program, or use F<perl.dll> from my
program.
=back
+=head2 C<``> and pipe-C<open> do not work under DOS.
+
+This may a variant of just L<"I cannot run external programs">, or a
+deeper problem. Basically: you I<need> B<RSX> (see L<"Prerequisites">)
+for these commands to work, and you may need a port of F<sh.exe> which
+understands command arguments. One of such ports is listed in
+L<"Prerequisites"> under B<RSX>.
+
+C<DPMI> is required for B<RSX>.
+
=head1 INSTALLATION
=head2 Automatic binary installation
-The most convinient way of installing perl is via perl installer
+The most convenient way of installing perl is via perl installer
F<install.exe>. Just follow the instructions, and 99% of the
installation blues would go away.
=head2 Manual binary installation
-As of version 5.00305, OS/2 perl binary distribution comes splitted
+As of version 5.00305, OS/2 perl binary distribution comes split
into 11 components. Unfortunately, to enable configurable binary
installation, the file paths in the C<zip> files are not absolute, but
relative to some directory.
(default with C<unzip>, specify C<-d> to C<pkunzip>). However, you
need to know where to extract the files. You need also to manually
change entries in F<Config.sys> to reflect where did you put the
-files.
+files. Note that if you have some primitive unzipper (like
+C<pkunzip>), you may get a lot of warnings/errors during
+unzipping. Upgrade to C<(w)unzip>.
Below is the sample of what to do to reproduce the configuration on my
machine:
unzip perl_sh.zip -d f:/bin
-This is used by perl to run external commands which explicitely
+This is used by perl to run external commands which explicitly
require shell, like the commands using I<redirection> and I<shell
metacharacters>. It is also used instead of explicit F</bin/sh>.
=head2 OS/2 F<.INF> file
-Most probably the most convinient form. View it as
+Most probably the most convenient form. View it as
view perl
view perl perlfunc
perldoc less
perldoc ExtUtils::MakeMaker
-to access the perl documention in the text form (note that you may get
+to access the perl documentation in the text form (note that you may get
better results using perl manpages).
Alternately, try running pod2text on F<.pod> files.
explore file:///f:/perllib/lib/pod/perl.html
-Alternatively you may be able to get these docs prebuild from C<CPAN>.
+Alternatively you may be able to get these docs prebuilt from C<CPAN>.
=head2 B<GNU> C<info> files
link386
shows you do not have it, do I<Selective install>, and choose C<Link
-object modules> in I<Optional system utilites/More>. If you get into
+object modules> in I<Optional system utilities/More>. If you get into
C<link386>, press C<Ctrl-C>.
=head2 Getting perl source
-You need to fetch the latest perl source (including developpers
+You need to fetch the latest perl source (including developers
releases). With some probability it is located in
http://www.perl.com/CPAN/src/5.0
If not, you may need to dig in the indices to find it in the directory
of the current maintainer.
-Quick cycle of developpers release may break the OS/2 build time to
+Quick cycle of developers release may break the OS/2 build time to
time, looking into
http://www.perl.com/CPAN/ports/os2/ilyaz/
lib/io_pipe.t 3 768 6 ?? % ??
lib/io_sock.t 3 768 5 ?? % ??
op/stat.t 56 5 8.93% 3-4, 20, 35, 39
- Failed 4/118 test scripts, 96.61% okay. 27/2445 subtests failed, 98.90% okay.
+ Failed 4/140 test scripts, 97.14% okay. 27/2937 subtests failed, 99.08% okay.
Note that using `make test' target two more tests may fail: C<op/exec:1>
because of (mis)feature of C<pdksh>, and C<lib/posix:15>, which checks
-that the buffers are not flushed on C<_exit>.
+that the buffers are not flushed on C<_exit> (this is a bug in the test
+which assumes that tty output is buffered).
+
+I submitted a patch to B<EMX> which makes it possible to fork() with EMX
+dynamic libraries loaded, which makes F<lib/io*> tests pass. This means
+that soon the number of failing tests may decrease yet more.
+
+However, the test F<lib/io_udp.t> is disabled, since it never ends, I
+do not know why.
The reasons for failed tests are:
Manually put F<perl_.exe> to a location on your C<PATH>.
Since C<perl_> has the extensions prebuilt, it does not suffer from
-the I<dynamic extensions + fork()> syndrom, thus the failing tests
+the I<dynamic extensions + fork()> syndrome, thus the failing tests
look like
Failed Test Status Wstat Total Fail Failed List of failed
Note that these functions are compatible with *nix, not with the older
ports of '94 - 95. The priorities are absolute, go from 32 to -95,
-lower is quickier. 0 is the default priority.
+lower is quicker. 0 is the default priority.
=head2 C<system()>
to DLLs having functions with REXX signature and to REXX runtime, to
OS/2 databases in the F<.INI> format, and to Extended Attributes.
-Two additional extensions by Andread Kaiser, C<OS2::UPM>, and
+Two additional extensions by Andreas Kaiser, C<OS2::UPM>, and
C<OS2::FTP>, are included into my ftp directory, mirrored on CPAN.
=head2 Prebuilt methods:
=item C<DynaLoader::mod2fname>
-used by C<DynaLoader> for DLL name mungling.
+used by C<DynaLoader> for DLL name mangling.
=item C<Cwd::current_drive()>
=item
-Since <lockf> is present in B<EMX>, but is not functional, the same is
-true for perl.
+Since <flock> is present in B<EMX>, but is not functional, the same is
+true for perl. Here is the list of things which may be "broken" on
+EMX (from EMX docs):
+
+ - The functions recvmsg(), sendmsg(), and socketpair() are not
+ implemented.
+ - sock_init() is not required and not implemented.
+ - flock() is not yet implemented (dummy function).
+ - kill:
+ Special treatment of PID=0, PID=1 and PID=-1 is not implemented.
+ - waitpid:
+ WUNTRACED
+ Not implemented.
+ waitpid() is not implemented for negative values of PID.
+
+Note that C<kill -9> does not work with the current version of EMX.
=item
-Since F<sh.exe> is used for globbing (see L<perlfunc/glob>), the bugs
+Since F<sh.exe> is used for globing (see L<perlfunc/glob>), the bugs
of F<sh.exe> plague perl as well.
In particular, uppercase letters do not work in C<[...]>-patterns with
=back
+=head2 Modifications
+
+Perl modifies some standard C library calls in the following ways:
+
+=over 9
+
+=item C<popen>
+
+C<my_popen> uses F<sh.exe> if shell is required, cf. L<"PERL_SH_DIR">.
+
+=item C<tmpnam>
+
+is created using C<TMP> or C<TEMP> environment variable, via
+C<tempnam>.
+
+=item C<tmpfile>
+
+If the current directory is not writable, file is created using modified
+C<tmpnam>, so there may be a race condition.
+
+=item C<ctermid>
+
+a dummy implementation.
+
+=item C<stat>
+
+C<os2_stat> special-cases F</dev/tty> and F</dev/con>.
+
+=back
+
=head1 Perl flavors
-Because of ideosyncrasies of OS/2 one cannot have all the eggs in the
+Because of idiosyncrasies of OS/2 one cannot have all the eggs in the
same basket (though C<EMX> environment tries hard to overcome this
limitations, so the situation may somehow improve). There are 4
executables for Perl provided by the distribution:
C<VIO> application.
It can load perl dynamic extensions, and it can fork(). Unfortunately,
-currently it cannot fork() with dynamic extensions loaded.
+with the current version of B<EMX> it cannot fork() with dynamic
+extensions loaded (may be fixed by patches to B<EMX>).
B<Note.> Keep in mind that fork() is needed to open a pipe to yourself.
I<This is also the only executable with does not require OS/2.> The
friends locked into C<M$> world would appreciate the fact that this
-executable runs under DOS, Win0.31, Win0.95 and WinNT with an
+executable runs under DOS, Win0.3*, Win0.95 and WinNT with an
appropriate extender. See L<"Other OSes">.
=head2 F<perl__.exe>
L<perldiag/"No Perl script found in input">), it should know when a
program I<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 convension which do not contain
+almost the only names allowed by this convention which do not contain
digits (which have absolutely different semantics).
=head2 Why dynamic linking?
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 patches only once, when they are
-loaded. The addresses of entry points into DLLs are guarantied to be
+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 developpers, since the above scheme makes it impossible
+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.
interpreter should be contained in a DLL, and the F<.EXE> file just loads
this DLL into memory and supplies command-arguments.
-This I<greately> increases the load time for the application (as well as
+This I<greatly> increases the load time for the application (as well as
the number of problems during compilation). Since interpreter is in a DLL,
the C<CRT> is basically forced to reside in a DLL as well (otherwise
extensions would not be able to use C<CRT>).
C<setpriority> and C<getpriority> are not compatible with earlier
ports by Andreas Kaiser. See C<"setpriority, getpriority">.
-=head2 DLL name mungling
+=head2 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
=head2 Calls to external programs
Due to a popular demand the perl external program calling has been
-changed wrt Andread Kaiser's port. I<If> perl needs to call an
+changed wrt Andreas Kaiser's port. I<If> perl needs to call an
external program I<via shell>, the F<f:/bin/sh.exe> will be called, or
whatever is the override, see L<"PERL_SH_DIR">.
B<Disadvantages:> currently F<sh.exe> of C<pdksh> calls external programs
via fork()/exec(), and there is I<no> functioning exec() on
OS/2. exec() is emulated by EMX by asyncroneous call while the caller
-waits for child completion (to pretend that the pid did not change). This
+waits for child completion (to pretend that the C<pid> did not change). This
means that 1 I<extra> copy of F<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).
-One can always start F<cmd.exe> explicitely via
+Note that this a lesser issue now when we do not spawn F<sh.exe>
+unless needed (metachars found).
+
+One can always start F<cmd.exe> explicitly via
system 'cmd', '/c', 'mycmd', 'arg1', 'arg2', ...
-If you need to use F<cmd.exe>, and do not want to hand-edit thousends of your
+If you need to use F<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;
OS/2 extensions
~~~~~~~~~~~~~~~
-I include 3 extensions by Andread Kaiser, OS2::REXX, OS2::UPM, and OS2::FTP,
+I include 3 extensions by Andreas Kaiser, OS2::REXX, OS2::UPM, and OS2::FTP,
into my ftp directory, mirrored on CPAN. I made
some minor changes needed to compile them by standard tools. I cannot
test UPM and FTP, so I will appreciate your feedback. Other extensions