in F<?:\JUST_ADD\view.exe>. This gives one an access to EMX's
F<.INF> docs as well (text form is available in F</emx/doc> in
-EMX's distribution).
+EMX's distribution). There is also a different viewer named xview.
-Note that if you have F<lynx.exe> installed, you can follow WWW links
+Note that if you have F<lynx.exe> or F<netscape.exe> installed, you can follow WWW links
from this document in F<.INF> format. If you have EMX docs installed
correctly, you can follow library links (you need to have C<view emxbook>
working by setting C<EMXBOOK> environment variable as it is described
=cut
-Contents
+Contents (This may be a little bit obsolete)
perlos2 - Perl under OS/2, DOS, Win0.3*, Win0.95 and WinNT.
- NAME
- SYNOPSIS
- DESCRIPTION
- - Target
- - Other OSes
- - Prerequisites
- - Starting Perl programs under OS/2 (and DOS and...)
- - Starting OS/2 (and DOS) programs under Perl
- Frequently asked questions
- - I cannot run external programs
- - I cannot embed perl into my program, or use perl.dll from my program.
- - `` and pipe-open do not work under DOS.
- - Cannot start find.exe "pattern" file
- INSTALLATION
- - Automatic binary installation
- - Manual binary installation
- - Warning
- Accessing documentation
- - OS/2 .INF file
- - Plain text
- - Manpages
- - HTML
- - GNU info files
- - .PDF files
- - LaTeX docs
- BUILD
- - Prerequisites
- - Getting perl source
- - Application of the patches
- - Hand-editing
- - Making
- - Testing
- - Installing the built perl
- - a.out-style build
- Build FAQ
- - Some / became \ in pdksh.
- - 'errno' - unresolved external
- - Problems with tr
- - Some problem (forget which ;-)
- - Library ... not found
- - Segfault in make
- Specific (mis)features of EMX port
- - setpriority, getpriority
- - system()
- - extproc on the first line
- - Additional modules:
- - Prebuilt methods:
- - Misfeatures
- - Modifications
- Perl flavors
- - perl.exe
- - perl_.exe
- - perl__.exe
- - perl___.exe
- - Why strange names?
- - Why dynamic linking?
- - Why chimera build?
- ENVIRONMENT
- - PERLLIB_PREFIX
- - PERL_BADLANG
- - PERL_BADFREE
- - PERL_SH_DIR
- - TMP or TEMP
- Evolution
- - Priorities
- - DLL name mangling
- - Threading
- - Calls to external programs
- - Memory allocation
- - Threads
- AUTHOR
- SEE ALSO
+ NAME
+ SYNOPSIS
+ DESCRIPTION
+ - Target
+ - Other OSes
+ - Prerequisites
+ - Starting Perl programs under OS/2 (and DOS and...)
+ - Starting OS/2 (and DOS) programs under Perl
+ Frequently asked questions
+ - "It does not work"
+ - I cannot run external programs
+ - I cannot embed perl into my program, or use perl.dll from my
+ - `` and pipe-open do not work under DOS.
+ - Cannot start find.exe "pattern" file
+ INSTALLATION
+ - Automatic binary installation
+ - Manual binary installation
+ - Warning
+ Accessing documentation
+ - OS/2 .INF file
+ - Plain text
+ - Manpages
+ - HTML
+ - GNU info files
+ - PDF files
+ - LaTeX docs
+ BUILD
+ - The short story
+ - Prerequisites
+ - Getting perl source
+ - Application of the patches
+ - Hand-editing
+ - Making
+ - Testing
+ - Installing the built perl
+ - a.out-style build
+ Build FAQ
+ - Some / became \ in pdksh.
+ - 'errno' - unresolved external
+ - Problems with tr or sed
+ - Some problem (forget which ;-)
+ - Library ... not found
+ - Segfault in make
+ - op/sprintf test failure
+ Specific (mis)features of OS/2 port
+ - setpriority, getpriority
+ - system()
+ - extproc on the first line
+ - Additional modules:
+ - Prebuilt methods:
+ - Prebuilt variables:
+ - Misfeatures
+ - Modifications
+ - Identifying DLLs
+ - Centralized management of resources
+ Perl flavors
+ - perl.exe
+ - perl_.exe
+ - perl__.exe
+ - perl___.exe
+ - Why strange names?
+ - Why dynamic linking?
+ - Why chimera build?
+ ENVIRONMENT
+ - PERLLIB_PREFIX
+ - PERL_BADLANG
+ - PERL_BADFREE
+ - PERL_SH_DIR
+ - USE_PERL_FLOCK
+ - TMP or TEMP
+ Evolution
+ - Text-mode filehandles
+ - Priorities
+ - DLL name mangling: pre 5.6.2
+ - DLL name mangling: 5.6.2 and beyond
+ - DLL forwarder generation
+ - Threading
+ - Calls to external programs
+ - Memory allocation
+ - Threads
+ BUGS
+ AUTHOR
+ SEE ALSO
=head1 DESCRIPTION
=head2 Target
-The target is to make OS/2 the best supported platform for
+The target is to make OS/2 one of the best supported platform for
using/building/developing Perl and I<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 B<too> hard).
=item *
-Some *nix programs use fork() a lot; with the mostly useful flavors of perl
-for OS/2 (there are several built simultaneously) this is supported;
-some flavors do not. Using fork() after I<use>ing dynamically loading
-extensions would not work with very old versions of EMX.
+Some *nix programs use fork() a lot; with the mostly useful flavors of
+perl for OS/2 (there are several built simultaneously) this is
+supported; but some flavors do not support this (e.g., when Perl is
+called from inside REXX). Using fork() after
+I<use>ing dynamically loading extensions would not work with I<very> old
+versions of EMX.
=item *
-You need a separate perl executable F<perl__.exe> (see L<perl__.exe>)
+You need a separate perl executable F<perl__.exe> (see L</perl__.exe>)
if you want to use PM code in your application (as Perl/Tk or OpenGL
Perl modules do) without having a text-mode window present.
=item *
There is no simple way to access WPS objects. The only way I know
-is via C<OS2::REXX> extension (see L<OS2::REXX>), and we do not have access to
+is via C<OS2::REXX> and C<SOM> extensions (see L<OS2::REXX>, L<SOM>).
+However, we do not have access to
convenience methods of Object-REXX. (Is it possible at all? I know
of no Object-REXX API.) The C<SOM> extension (currently in alpha-text)
-may eventually remove this shortcoming.
+may eventually remove this shortcoming; however, due to the fact that
+DII is not supported by the C<SOM> module, using C<SOM> is not as
+convenient as one would like it.
=back
environments. This depends on the features the I<extender> - most
probably RSX - decided to implement.
-Cf. L<Prerequisites>.
+Cf. L</Prerequisites>.
=head2 Prerequisites
EMX runtime is required (may be substituted by 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
+external support by binding F<emx.exe>/F<rsx.exe> to it, see C<emxbind>. Note
that under DOS for best results one should use RSX runtime, which
has much more functions working (like C<fork>, C<popen> and so on). In
fact RSX is required if there is no VCPI present. Note the
-RSX requires DPMI.
+RSX requires DPMI. Many implementations of DPMI are known to be very
+buggy, beware!
Only the latest runtime is supported, currently C<0.9d fix 03>. Perl may run
under earlier versions of EMX, but this is not tested.
One can get different parts of EMX from, say
- http://www.leo.org/pub/comp/os/os2/leo/gnu/emx+gcc/
- http://powerusersbbs.com/pub/os2/dev/ [EMX+GCC Development]
- http://hobbes.nmsu.edu/pub/os2/dev/emx/v0.9d/
+ ftp://crydee.sai.msu.ru/pub/comp/os/os2/leo/gnu/emx+gcc/
+ http://hobbes.nmsu.edu/h-browse.php?dir=/pub/os2/dev/emx/v0.9d/
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
+B<NOTE>. When using F<emx.exe>/F<rsx.exe>, it is enough to have them on your path. One
does not need to specify them explicitly (though this
emx perl_.exe -de 0
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
+ http://cd.textfiles.com/hobbesos29804/disk1/EMX09C/
+ ftp://crydee.sai.msu.ru/pub/comp/os/os2/leo/gnu/emx+gcc/contrib/
Contact the author on C<rainer@mathematik.uni-bielefeld.de>.
The latest F<sh.exe> with DOS hooks is available in
- ftp://ftp.math.ohio-state.edu/pub/users/ilya/os2/
+ http://www.ilyaz.org/software/os2/
as F<sh_dos.zip> or under similar names starting with C<sh>, C<pdksh> etc.
=item 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.
+Perl does not care about file systems, but the perl library contains
+many files with long names, so to install it 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,
or in configurable location (see L<"PERL_SH_DIR">).
For best results use EMX pdksh. The standard binary (5.2.14 or later) runs
-under DOS (with L<RSX>) as well, see
+under DOS (with L</RSX>) as well, see
- ftp://ftp.math.ohio-state.edu/pub/users/ilya/os2/
+ http://www.ilyaz.org/software/os2/
=back
perl foo.pl arg1 arg2 arg3
If you want to specify perl options C<-my_opts> to the perl itself (as
-opposed to to your program), use
+opposed to your program), use
perl -my_opts foo.pl arg1 arg2 arg3
There are also endless possibilities to use I<executable extensions> of
4os2, I<associations> of WPS and so on... However, if you use
*nixish shell (like F<sh.exe> supplied in the binary distribution),
-you need to follow the syntax specified in L<perlrun/"Switches">.
+you need to follow the syntax specified in L<perlrun/"Command Switches">.
-Note that B<-S> switch enables a search with additional extensions
+Note that B<-S> switch supports scripts with additional extensions
F<.cmd>, F<.btm>, F<.bat>, F<.pl> as well.
=head2 Starting OS/2 (and DOS) programs under Perl
=item 6
If the executable called by system()/exec()/pipe-open()/C<``> is not
-found;
+found (is not this remark obsolete?);
=item 7
-For globbing (see L<perlfunc/glob>, L<perlop/"I/O Operators">).
+For globbing (see L<perlfunc/glob>, L<perlop/"I/O Operators">)
+(obsolete? Perl uses builtin globbing nowadays...).
=back
Perl starts scripts which begin with cookies
C<extproc> or C<#!> directly, without an intervention of shell. Perl uses the
same algorithm to find the executable as F<pdksh>: if the path
-on C<#!> line does not work, and contains C</>, then the executable
+on C<#!> line does not work, and contains C</>, then the directory
+part of the executable is ignored, and the executable
is searched in F<.> and on C<PATH>. To find arguments for these scripts
Perl uses a different algorithm than F<pdksh>: up to 3 arguments are
recognized, and trailing whitespace is stripped.
C<$ENV{COMSPEC} /c> is used (or a hardwired guess if C<$ENV{COMSPEC}> is
not set).
-If starting scripts directly, Perl will use exactly the same algorithm as for
+When starting scripts directly, Perl uses exactly the same algorithm as for
the search of script given by B<-S> command-line option: it will look in
the current directory, then on components of C<$ENV{PATH}> using the
following order of appended extensions: no extension, F<.cmd>, F<.btm>,
Note that Perl will start to look for scripts only if OS/2 cannot start the
specified application, thus C<system 'blah'> will not look for a script if
-there is an executable file F<blah.exe> I<anywhere> on C<PATH>.
-
-Note also that executable files on OS/2 can have an arbitrary extension,
-but F<.exe> will be automatically appended if no dot is present in the name.
-The workaround as as simple as that: since F<blah.> and F<blah> denote the
-same file, to start an executable residing in file F<n:/bin/blah> (no
-extension) give an argument C<n:/bin/blah.> (dot appended) to system().
-
-Perl will correctly start PM programs from VIO (=text-mode) Perl process;
+there is an executable file F<blah.exe> I<anywhere> on C<PATH>. In
+other words, C<PATH> is essentially searched twice: once by the OS for
+an executable, then by Perl for scripts.
+
+Note also that executable files on OS/2 can have an arbitrary extension, but
+F<.exe> will be automatically appended if no dot is present in the name. The
+workaround is as simple as that: since F<blah.> and F<blah> denote the same
+file (at list on FAT and HPFS file systems), to start an executable residing in
+file F<n:/bin/blah> (no extension) give an argument C<n:/bin/blah.> (dot
+appended) to system().
+
+Perl will start PM programs from VIO (=text-mode) Perl process in a
+separate PM session;
the opposite is not true: when you start a non-PM program from a PM
-Perl process, it would not run it in a separate session. If a separate
+Perl process, Perl would not run it in a separate session. If a separate
session is desired, either ensure
that shell will be used, as in C<system 'cmd /c myprog'>, or start it using
optional arguments to system() documented in C<OS2::Process> module. This
=item *
Did you run your programs with C<-w> switch? See
-L<Starting OS/2 (and DOS) programs under Perl>.
+L<Starting OSE<sol>2 (and DOS) programs under Perl>.
=item *
=item Is your program EMX-compiled with C<-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.
+Well, nowadays Perl DLL should be usable from a differently compiled
+program too... If you can run Perl code from REXX scripts (see
+L<OS2::REXX>), then there are some other aspect of interaction which
+are overlooked by the current hackish code to support
+differently-compiled principal programs.
+
+If everything else fails, 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.
=item Did you use L<ExtUtils::Embed>?
-I had reports it does not work. Somebody would need to fix it.
+Some time ago I had reports it does not work. Nowadays it is checked
+in the Perl test suite, so grep F<./t> subdirectory of the build tree
+(as well as F<*.t> files in the F<./lib> subdirectory) to find how it
+should be done "correctly".
=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> RSX (see L<"Prerequisites">)
+deeper problem. Basically: you I<need> 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 RSX. Do not forget to set variable
+L</Prerequisites> under RSX. Do not forget to set variable
C<L<"PERL_SH_DIR">> as well.
DPMI is required for RSX.
=head2 Cannot start C<find.exe "pattern" file>
+The whole idea of the "standard C API to start applications" is that
+the forms C<foo> and C<"foo"> of program arguments are completely
+interchangeable. F<find> breaks this paradigm;
+
+ find "pattern" file
+ find pattern file
+
+are not equivalent; F<find> cannot be started directly using the above
+API. One needs a way to surround the doublequotes in some other
+quoting construction, necessarily having an extra non-Unixish shell in
+between.
+
Use one of
system 'cmd', '/c', 'find "pattern" file';
This would start F<find.exe> via F<cmd.exe> via C<sh.exe> via
C<perl.exe>, but this is a price to pay if you want to use
-non-conforming program. In fact F<find.exe> cannot be started at all
-using C library API only. Otherwise the following command-lines would be
-equivalent:
-
- find "pattern" file
- find pattern file
+non-conforming program.
=head1 INSTALLATION
emxrev
-A folder is created on your desktop which contains some useful
-objects.
+Binary installer also creates a folder on your desktop with some useful
+objects. If you need to change some aspects of the work of the binary
+installer, feel free to edit the file F<Perl.pkg>. This may be useful
+e.g., if you need to run the installer many times and do not want to
+make many interactive changes in the GUI.
B<Things not taken care of by automatic binary installation:>
While most important values in this file I<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.
+data, please keep me informed if you find one. Moreover, manual
+changes to the installed version may need to be accompanied by an edit
+of this file.
=back
B<NOTE>. Because of a typo the binary installer of 5.00305
would install a variable C<PERL_SHPATH> into F<Config.sys>. Please
-remove this variable and put C<L<PERL_SH_DIR>> instead.
+remove this variable and put C<L</PERL_SH_DIR>> instead.
=head2 Manual binary installation
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. Note that if you have some primitive unzipper (like
-pkunzip), you may get a lot of warnings/errors during
+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:
+machine. In F<VIEW.EXE> you can press C<Ctrl-Insert> now, and
+cut-and-paste from the resulting file - created in the directory you
+started F<VIEW.EXE> from.
+
+For each component, we mention environment variables related to each
+installation directory. Either choose directories to match your
+values of the variables, or create/append-to variables to take into
+account the directories.
=over 3
=item Additional Perl modules
- unzip perl_ste.zip -d f:/perllib/lib/site_perl/5.8.3/
+ unzip perl_ste.zip -d f:/perllib/lib/site_perl/5.19.3/
Same remark as above applies. Additionally, if this directory is not
one of directories on @INC (and @INC is influenced by C<PERLLIB_PREFIX>), you
variable. Do not use C<PERL5LIB> unless you have it set already. See
L<perl/"ENVIRONMENT">.
+B<[Check whether this extraction directory is still applicable with
+the new directory structure layout!]>
+
=item Tools to compile Perl modules
unzip perl_blb.zip -d f:/perllib/lib
unzip perl_man.zip -d f:/perllib/man
This directory should better be on C<MANPATH>. You need to have a
-working man to access these files.
+working F<man> to access these files.
=item Manpages for Perl modules
This is used by the C<perldoc> program (see L<perldoc>), and may be used to
generate HTML documentation usable by WWW browsers, and
documentation in zillions of other formats: C<info>, C<LaTeX>,
-C<Acrobat>, C<FrameMaker> and so on.
+C<Acrobat>, C<FrameMaker> and so on. [Use programs such as
+F<pod2latex> etc.]
=item Perl manual in F<.INF> format
Set C<PERL_SH_DIR> (see L<"PERL_SH_DIR">) if you move F<sh.exe> from
the above location.
-B<Note.> It may be possible to use some other sh-compatible shell
-(file globbing - if done via shell - may break).
+B<Note.> It may be possible to use some other sh-compatible shell (untested).
=back
The automatic and manual perl installation leave precompiled paths
inside perl executables. While these paths are overwriteable (see
-L<"PERLLIB_PREFIX">, L<"PERL_SH_DIR">), one may get better results by
+L<"PERLLIB_PREFIX">, L<"PERL_SH_DIR">), some people may prefer
binary editing of paths inside the executables/DLLs.
=head1 Accessing documentation
=head2 Manpages
-If you have man installed on your system, and you installed perl
+If you have F<man> installed on your system, and you installed perl
manpages, use something like this:
man perlfunc
=head2 GNU C<info> files
Users of Emacs would appreciate it very much, especially with
-C<CPerl> mode loaded. You need to get latest C<pod2info> from C<CPAN>,
-or, alternately, prebuilt info pages.
+C<CPerl> mode loaded. You need to get latest C<pod2texi> from C<CPAN>,
+or, alternately, the prebuilt info pages.
-=head2 F<.PDF> files
+=head2 F<PDF> files
-for C<Acrobat> are available on CPAN (for slightly old version of
+for C<Acrobat> are available on CPAN (may be for slightly older version of
perl).
=head2 C<LaTeX> docs
=head1 BUILD
-Here we discuss how to build Perl under OS/2. There is an alternative
-(but maybe older) view on http://www.shadow.net/~troc/os2perl.html
+Here we discuss how to build Perl under OS/2.
=head2 The short story
make aout_install
This puts the executables in f:/perllib/bin. Manually move them to the
-C<PATH>, manually move the built F<perl*.dll> to C<LIBPATH> (here F<*> is
-a not-very-meaningful hex checksum), and run
+C<PATH>, manually move the built F<perl*.dll> to C<LIBPATH> (here for
+Perl DLL F<*> is a not-very-meaningful hex checksum), and run
make installcmd INSTALLCMDDIR=d:/ir/on/path
+Assuming that the C<man>-files were put on an appropriate location,
+this completes the installation of minimal Perl system. (The binary
+distribution contains also a lot of additional modules, and the
+documentation in INF format.)
+
What follows is a detailed guide through these steps.
=head2 Prerequisites
Check that you have B<BSD> libraries and headers installed, and -
optionally - Berkeley DB headers and libraries, and crypt.
-Possible locations to get this from are
+Possible locations to get the files:
- 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/
+
+ ftp://ftp.uni-heidelberg.de/pub/os2/unix/
+ http://hobbes.nmsu.edu/h-browse.php?dir=/pub/os2
+ http://cd.textfiles.com/hobbesos29804/disk1/DEV32/
+ http://cd.textfiles.com/hobbesos29804/disk1/EMX09C/
It is reported that the following archives contain enough utils to
build perl: F<gnufutil.zip>, F<gnusutil.zip>, F<gnututil.zip>, F<gnused.zip>,
-F<gnupatch.zip>, F<gnuawk.zip>, F<gnumake.zip>, F<bsddev.zip> and
+F<gnupatch.zip>, F<gnuawk.zip>, F<gnumake.zip>, F<gnugrep.zip>, F<bsddev.zip> and
F<ksh527rt.zip> (or a later version). Note that all these utilities are
known to be available from LEO:
- ftp://ftp.leo.org/pub/comp/os/os2/leo/gnu
+ ftp://crydee.sai.msu.ru/pub/comp/os/os2/leo/gnu/
+
+Note also that the F<db.lib> and F<db.a> from the EMX distribution
+are not suitable for multi-threaded compile (even single-threaded
+flavor of Perl uses multi-threaded C RTL, for
+compatibility with XFree86-OS/2). Get a corrected one from
+
+ http://www.ilyaz.org/software/os2/db_mt.zip
If you have I<exactly the same version of Perl> installed already,
make sure that no copies or perl are currently running. Later steps
of the build may fail since an older version of F<perl.dll> loaded into
-memory may be found.
+memory may be found. Running C<make test> becomes meaningless, since
+the test are checking a previous build of perl (this situation is detected
+and reported by F<lib/os2_base.t> test). Do not forget to unset
+C<PERL_EMXLOAD_SEC> in environment.
Also make sure that you have F</tmp> directory on the current drive,
and F<.> directory in your C<LIBPATH>. One may try to correct the
latter condition by
- set BEGINLIBPATH .
+ set BEGINLIBPATH .\.
-if you use something like F<CMD.EXE> or latest versions of F<4os2.exe>.
+if you use something like F<CMD.EXE> or latest versions of
+F<4os2.exe>. (Setting BEGINLIBPATH to just C<.> is ignored by the
+OS/2 kernel.)
Make sure your gcc is good for C<-Zomf> linking: run C<omflibs>
script in F</emx/lib> directory.
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
- http://www.perl.com/CPAN/src/5.0/unsupported
+ http://www.cpan.org/src/
+ http://www.cpan.org/src/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/
+ http://www.cpan.org/ports/os2/
may indicate the latest release which was publicly released by the
maintainer. Note that the release may include some additional patches
gnupatch -p0 < os2\diff.configure
You may also need to apply the patches supplied with the binary
-distribution of perl.
-
-Note also that the F<db.lib> and F<db.a> from the EMX distribution
-are not suitable for multi-threaded compile (even single-threaded
-flavor of Perl uses multi-threaded C RTL, for
-compatibility with XFree86-OS/2). Get a corrected one from
-
- ftp://ftp.math.ohio-state.edu/pub/users/ilya/os2/db_mt.zip
+distribution of perl. It also makes sense to look on the
+perl5-porters mailing list for the latest OS/2-related patches (see
+L<http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/>). Such
+patches usually contain strings C</os2/> and C<patch>, so it makes
+sense looking for these strings.
=head2 Hand-editing
make test
-All tests should succeed (with some of them skipped).
+All tests should succeed (with some of them skipped). If you have the
+same version of Perl installed, it is crucial that you have C<.> early
+in your LIBPATH (or in BEGINLIBPATH), otherwise your tests will most
+probably test the wrong version of Perl.
Some tests may generate extra messages similar to
=head2 Installing the built perl
-If you haven't yet moved perl.dll onto LIBPATH, do it now.
+If you haven't yet moved C<perl*.dll> onto LIBPATH, do it now.
Run
to convert perl utilities to F<.cmd> files and put them on
PATH. You need to put F<.EXE>-utilities on path manually. They are
installed in C<$prefix/bin>, here C<$prefix> is what you gave to
-F<Configure>, see L<Making>.
+F<Configure>, see L</Making>.
+
+If you use C<man>, either move the installed F<*/man/> directories to
+your C<MANPATH>, or modify C<MANPATH> to match the location. (One
+could have avoided this by providing a correct C<manpath> option to
+F<./Configure>, or editing F<./config.sh> between configuring and
+making steps.)
=head2 C<a.out>-style build
first.
+=head1 Building a binary distribution
+
+[This section provides a short overview only...]
+
+Building should proceed differently depending on whether the version of perl
+you install is already present and used on your system, or is a new version
+not yet used. The description below assumes that the version is new, so
+installing its DLLs and F<.pm> files will not disrupt the operation of your
+system even if some intermediate steps are not yet fully working.
+
+The other cases require a little bit more convoluted procedures. Below I
+suppose that the current version of Perl is C<5.8.2>, so the executables are
+named accordingly.
+
+=over
+
+=item 1.
+
+Fully build and test the Perl distribution. Make sure that no tests are
+failing with C<test> and C<aout_test> targets; fix the bugs in Perl and
+the Perl test suite detected by these tests. Make sure that C<all_test>
+make target runs as clean as possible. Check that F<os2/perlrexx.cmd>
+runs fine.
+
+=item 2.
+
+Fully install Perl, including C<installcmd> target. Copy the generated DLLs
+to C<LIBPATH>; copy the numbered Perl executables (as in F<perl5.8.2.exe>)
+to C<PATH>; copy C<perl_.exe> to C<PATH> as C<perl_5.8.2.exe>. Think whether
+you need backward-compatibility DLLs. In most cases you do not need to install
+them yet; but sometime this may simplify the following steps.
+
+=item 3.
+
+Make sure that C<CPAN.pm> can download files from CPAN. If not, you may need
+to manually install C<Net::FTP>.
+
+=item 4.
+
+Install the bundle C<Bundle::OS2_default>
+
+ perl5.8.2 -MCPAN -e "install Bundle::OS2_default" < nul |& tee 00cpan_i_1
+
+This may take a couple of hours on 1GHz processor (when run the first time).
+And this should not be necessarily a smooth procedure. Some modules may not
+specify required dependencies, so one may need to repeat this procedure several
+times until the results stabilize.
+
+ perl5.8.2 -MCPAN -e "install Bundle::OS2_default" < nul |& tee 00cpan_i_2
+ perl5.8.2 -MCPAN -e "install Bundle::OS2_default" < nul |& tee 00cpan_i_3
+
+Even after they stabilize, some tests may fail.
+
+Fix as many discovered bugs as possible. Document all the bugs which are not
+fixed, and all the failures with unknown reasons. Inspect the produced logs
+F<00cpan_i_1> to find suspiciously skipped tests, and other fishy events.
+
+Keep in mind that I<installation> of some modules may fail too: for example,
+the DLLs to update may be already loaded by F<CPAN.pm>. Inspect the C<install>
+logs (in the example above F<00cpan_i_1> etc) for errors, and install things
+manually, as in
+
+ cd $CPANHOME/.cpan/build/Digest-MD5-2.31
+ make install
+
+Some distributions may fail some tests, but you may want to install them
+anyway (as above, or via C<force install> command of C<CPAN.pm> shell-mode).
+
+Since this procedure may take quite a long time to complete, it makes sense
+to "freeze" your CPAN configuration by disabling periodic updates of the
+local copy of CPAN index: set C<index_expire> to some big value (I use 365),
+then save the settings
+
+ CPAN> o conf index_expire 365
+ CPAN> o conf commit
+
+Reset back to the default value C<1> when you are finished.
+
+=item 5.
+
+When satisfied with the results, rerun the C<installcmd> target. Now you
+can copy C<perl5.8.2.exe> to C<perl.exe>, and install the other OMF-build
+executables: C<perl__.exe> etc. They are ready to be used.
+
+=item 6.
+
+Change to the C<./pod> directory of the build tree, download the Perl logo
+F<CamelGrayBig.BMP>, and run
+
+ ( perl2ipf > perl.ipf ) |& tee 00ipf
+ ipfc /INF perl.ipf |& tee 00inf
+
+This produces the Perl docs online book C<perl.INF>. Install in on
+C<BOOKSHELF> path.
+
+=item 7.
+
+Now is the time to build statically linked executable F<perl_.exe> which
+includes newly-installed via C<Bundle::OS2_default> modules. Doing testing
+via C<CPAN.pm> is going to be painfully slow, since it statically links
+a new executable per XS extension.
+
+Here is a possible workaround: create a toplevel F<Makefile.PL> in
+F<$CPANHOME/.cpan/build/> with contents being (compare with L<Making
+executables with a custom collection of statically loaded extensions>)
+
+ use ExtUtils::MakeMaker;
+ WriteMakefile NAME => 'dummy';
+
+execute this as
+
+ perl_5.8.2.exe Makefile.PL <nul |& tee 00aout_c1
+ make -k all test <nul |& 00aout_t1
+
+Again, this procedure should not be absolutely smooth. Some C<Makefile.PL>'s
+in subdirectories may be buggy, and would not run as "child" scripts. The
+interdependency of modules can strike you; however, since non-XS modules
+are already installed, the prerequisites of most modules have a very good
+chance to be present.
+
+If you discover some glitches, move directories of problematic modules to a
+different location; if these modules are non-XS modules, you may just ignore
+them - they are already installed; the remaining, XS, modules you need to
+install manually one by one.
+
+After each such removal you need to rerun the C<Makefile.PL>/C<make> process;
+usually this procedure converges soon. (But be sure to convert all the
+necessary external C libraries from F<.lib> format to F<.a> format: run one of
+
+ emxaout foo.lib
+ emximp -o foo.a foo.lib
+
+whichever is appropriate.) Also, make sure that the DLLs for external
+libraries are usable with with executables compiled without C<-Zmtd> options.
+
+When you are sure that only a few subdirectories
+lead to failures, you may want to add C<-j4> option to C<make> to speed up
+skipping subdirectories with already finished build.
+
+When you are satisfied with the results of tests, install the build C libraries
+for extensions:
+
+ make install |& tee 00aout_i
+
+Now you can rename the file F<./perl.exe> generated during the last phase
+to F<perl_5.8.2.exe>; place it on C<PATH>; if there is an inter-dependency
+between some XS modules, you may need to repeat the C<test>/C<install> loop
+with this new executable and some excluded modules - until the procedure
+converges.
+
+Now you have all the necessary F<.a> libraries for these Perl modules in the
+places where Perl builder can find it. Use the perl builder: change to an
+empty directory, create a "dummy" F<Makefile.PL> again, and run
+
+ perl_5.8.2.exe Makefile.PL |& tee 00c
+ make perl |& tee 00p
+
+This should create an executable F<./perl.exe> with all the statically loaded
+extensions built in. Compare the generated F<perlmain.c> files to make sure
+that during the iterations the number of loaded extensions only increases.
+Rename F<./perl.exe> to F<perl_5.8.2.exe> on C<PATH>.
+
+When it converges, you got a functional variant of F<perl_5.8.2.exe>; copy it
+to C<perl_.exe>. You are done with generation of the local Perl installation.
+
+=item 8.
+
+Make sure that the installed modules are actually installed in the location
+of the new Perl, and are not inherited from entries of @INC given for
+inheritance from the older versions of Perl: set C<PERLLIB_582_PREFIX> to
+redirect the new version of Perl to a new location, and copy the installed
+files to this new location. Redo the tests to make sure that the versions of
+modules inherited from older versions of Perl are not needed.
+
+Actually, the log output of L<pod2ipf(1)> during the step 6 gives a very detailed
+info about which modules are loaded from which place; so you may use it as
+an additional verification tool.
+
+Check that some temporary files did not make into the perl install tree.
+Run something like this
+
+ pfind . -f "!(/\.(pm|pl|ix|al|h|a|lib|txt|pod|imp|bs|dll|ld|bs|inc|xbm|yml|cgi|uu|e2x|skip|packlist|eg|cfg|html|pub|enc|all|ini|po|pot)$/i or /^\w+$/") | less
+
+in the install tree (both top one and F<sitelib> one).
+
+Compress all the DLLs with F<lxlite>. The tiny F<.exe> can be compressed with
+C</c:max> (the bug only appears when there is a fixup in the last 6 bytes of a
+page (?); since the tiny executables are much smaller than a page, the bug
+will not hit). Do not compress C<perl_.exe> - it would not work under DOS.
+
+=item 9.
+
+Now you can generate the binary distribution. This is done by running the
+test of the CPAN distribution C<OS2::SoftInstaller>. Tune up the file
+F<test.pl> to suit the layout of current version of Perl first. Do not
+forget to pack the necessary external DLLs accordingly. Include the
+description of the bugs and test suite failures you could not fix. Include
+the small-stack versions of Perl executables from Perl build directory.
+
+Include F<perl5.def> so that people can relink the perl DLL preserving
+the binary compatibility, or can create compatibility DLLs. Include the diff
+files (C<diff -pu old new>) of fixes you did so that people can rebuild your
+version. Include F<perl5.map> so that one can use remote debugging.
+
+=item 10.
+
+Share what you did with the other people. Relax. Enjoy fruits of your work.
+
+=item 11.
+
+Brace yourself for thanks, bug reports, hate mail and spam coming as result
+of the previous step. No good deed should remain unpunished!
+
+=back
+
+=head1 Building custom F<.EXE> files
+
+The Perl executables can be easily rebuilt at any moment. Moreover, one can
+use the I<embedding> interface (see L<perlembed>) to make very customized
+executables.
+
+=head2 Making executables with a custom collection of statically loaded extensions
+
+It is a little bit easier to do so while I<decreasing> the list of statically
+loaded extensions. We discuss this case only here.
+
+=over
+
+=item 1.
+
+Change to an empty directory, and create a placeholder <Makefile.PL>:
+
+ use ExtUtils::MakeMaker;
+ WriteMakefile NAME => 'dummy';
+
+=item 2.
+
+Run it with the flavor of Perl (F<perl.exe> or F<perl_.exe>) you want to
+rebuild.
+
+ perl_ Makefile.PL
+
+=item 3.
+
+Ask it to create new Perl executable:
+
+ make perl
+
+(you may need to manually add C<PERLTYPE=-DPERL_CORE> to this commandline on
+some versions of Perl; the symptom is that the command-line globbing does not
+work from OS/2 shells with the newly-compiled executable; check with
+
+ .\perl.exe -wle "print for @ARGV" *
+
+).
+
+=item 4.
+
+The previous step created F<perlmain.c> which contains a list of newXS() calls
+near the end. Removing unnecessary calls, and rerunning
+
+ make perl
+
+will produce a customized executable.
+
+=back
+
+=head2 Making executables with a custom search-paths
+
+The default perl executable is flexible enough to support most usages.
+However, one may want something yet more flexible; for example, one may want
+to find Perl DLL relatively to the location of the EXE file; or one may want
+to ignore the environment when setting the Perl-library search patch, etc.
+
+If you fill comfortable with I<embedding> interface (see L<perlembed>), such
+things are easy to do repeating the steps outlined in L<Making
+executables with a custom collection of statically loaded extensions>, and
+doing more comprehensive edits to main() of F<perlmain.c>. The people with
+little desire to understand Perl can just rename main(), and do necessary
+modification in a custom main() which calls the renamed function in appropriate
+time.
+
+However, there is a third way: perl DLL exports the main() function and several
+callbacks to customize the search path. Below is a complete example of a
+"Perl loader" which
+
+=over
+
+=item 1.
+
+Looks for Perl DLL in the directory C<$exedir/../dll>;
+
+=item 2.
+
+Prepends the above directory to C<BEGINLIBPATH>;
+
+=item 3.
+
+Fails if the Perl DLL found via C<BEGINLIBPATH> is different from what was
+loaded on step 1; e.g., another process could have loaded it from C<LIBPATH>
+or from a different value of C<BEGINLIBPATH>. In these cases one needs to
+modify the setting of the system so that this other process either does not
+run, or loads the DLL from C<BEGINLIBPATH> with C<LIBPATHSTRICT=T> (available
+with kernels after September 2000).
+
+=item 4.
+
+Loads Perl library from C<$exedir/../dll/lib/>.
+
+=item 5.
+
+Uses Bourne shell from C<$exedir/../dll/sh/ksh.exe>.
+
+=back
+
+For best results compile the C file below with the same options as the Perl
+DLL. However, a lot of functionality will work even if the executable is not
+an EMX applications, e.g., if compiled with
+
+ gcc -Wall -DDOSISH -DOS2=1 -O2 -s -Zomf -Zsys perl-starter.c \
+ -DPERL_DLL_BASENAME=\"perl312F\" -Zstack 8192 -Zlinker /PM:VIO
+
+Here is the sample C file:
+
+ #define INCL_DOS
+ #define INCL_NOPM
+ /* These are needed for compile if os2.h includes os2tk.h, not os2emx.h */
+ #define INCL_DOSPROCESS
+ #include <os2.h>
+
+ #include "EXTERN.h"
+ #define PERL_IN_MINIPERLMAIN_C
+ #include "perl.h"
+
+ static char *me;
+ HMODULE handle;
+
+ static void
+ die_with(char *msg1, char *msg2, char *msg3, char *msg4)
+ {
+ ULONG c;
+ char *s = " error: ";
+
+ DosWrite(2, me, strlen(me), &c);
+ DosWrite(2, s, strlen(s), &c);
+ DosWrite(2, msg1, strlen(msg1), &c);
+ DosWrite(2, msg2, strlen(msg2), &c);
+ DosWrite(2, msg3, strlen(msg3), &c);
+ DosWrite(2, msg4, strlen(msg4), &c);
+ DosWrite(2, "\r\n", 2, &c);
+ exit(255);
+ }
+
+ typedef ULONG (*fill_extLibpath_t)(int type, char *pre, char *post, int replace, char *msg);
+ typedef int (*main_t)(int type, char *argv[], char *env[]);
+ typedef int (*handler_t)(void* data, int which);
+
+ #ifndef PERL_DLL_BASENAME
+ # define PERL_DLL_BASENAME "perl"
+ #endif
+
+ static HMODULE
+ load_perl_dll(char *basename)
+ {
+ char buf[300], fail[260];
+ STRLEN l, dirl;
+ fill_extLibpath_t f;
+ ULONG rc_fullname;
+ HMODULE handle, handle1;
+
+ if (_execname(buf, sizeof(buf) - 13) != 0)
+ die_with("Can't find full path: ", strerror(errno), "", "");
+ /* XXXX Fill 'me' with new value */
+ l = strlen(buf);
+ while (l && buf[l-1] != '/' && buf[l-1] != '\\')
+ l--;
+ dirl = l - 1;
+ strcpy(buf + l, basename);
+ l += strlen(basename);
+ strcpy(buf + l, ".dll");
+ if ( (rc_fullname = DosLoadModule(fail, sizeof fail, buf, &handle)) != 0
+ && DosLoadModule(fail, sizeof fail, basename, &handle) != 0 )
+ die_with("Can't load DLL ", buf, "", "");
+ if (rc_fullname)
+ return handle; /* was loaded with short name; all is fine */
+ if (DosQueryProcAddr(handle, 0, "fill_extLibpath", (PFN*)&f))
+ die_with(buf, ": DLL exports no symbol ", "fill_extLibpath", "");
+ buf[dirl] = 0;
+ if (f(0 /*BEGINLIBPATH*/, buf /* prepend */, NULL /* append */,
+ 0 /* keep old value */, me))
+ die_with(me, ": prepending BEGINLIBPATH", "", "");
+ if (DosLoadModule(fail, sizeof fail, basename, &handle1) != 0)
+ die_with(me, ": finding perl DLL again via BEGINLIBPATH", "", "");
+ buf[dirl] = '\\';
+ if (handle1 != handle) {
+ if (DosQueryModuleName(handle1, sizeof(fail), fail))
+ strcpy(fail, "???");
+ die_with(buf, ":\n\tperl DLL via BEGINLIBPATH is different: \n\t",
+ fail,
+ "\n\tYou may need to manipulate global BEGINLIBPATH and LIBPATHSTRICT"
+ "\n\tso that the other copy is loaded via BEGINLIBPATH.");
+ }
+ return handle;
+ }
+
+ int
+ main(int argc, char **argv, char **env)
+ {
+ main_t f;
+ handler_t h;
+
+ me = argv[0];
+ /**/
+ handle = load_perl_dll(PERL_DLL_BASENAME);
+
+ if (DosQueryProcAddr(handle, 0, "Perl_OS2_handler_install", (PFN*)&h))
+ die_with(PERL_DLL_BASENAME, ": DLL exports no symbol ", "Perl_OS2_handler_install", "");
+ if ( !h((void *)"~installprefix", Perlos2_handler_perllib_from)
+ || !h((void *)"~dll", Perlos2_handler_perllib_to)
+ || !h((void *)"~dll/sh/ksh.exe", Perlos2_handler_perl_sh) )
+ die_with(PERL_DLL_BASENAME, ": Can't install @INC manglers", "", "");
+
+ if (DosQueryProcAddr(handle, 0, "dll_perlmain", (PFN*)&f))
+ die_with(PERL_DLL_BASENAME, ": DLL exports no symbol ", "dll_perlmain", "");
+ return f(argc, argv, env);
+ }
+
+
=head1 Build FAQ
=head2 Some C</> became C<\> in pdksh.
-You have a very old pdksh. See L<Prerequisites>.
+You have a very old pdksh. See L</Prerequisites>.
=head2 C<'errno'> - unresolved external
-You do not have MT-safe F<db.lib>. See L<Prerequisites>.
+You do not have MT-safe F<db.lib>. See L</Prerequisites>.
=head2 Problems with tr or sed
=head2 Library ... not found
-You did not run C<omflibs>. See L<Prerequisites>.
+You did not run C<omflibs>. See L</Prerequisites>.
=head2 Segfault in make
-You use an old version of GNU make. See L<Prerequisites>.
+You use an old version of GNU make. See L</Prerequisites>.
=head2 op/sprintf test failure
ports of '94 - 95. The priorities are absolute, go from 32 to -95,
lower is quicker. 0 is the default priority.
-B<WARNING>. Calling C<getpriority> on a non-existing process can lock the
-system before Warp3 fixpak22.
+B<WARNING>. Calling C<getpriority> on a non-existing process could lock
+the system before Warp3 fixpak22. Starting with Warp3, Perl will use
+a workaround: it aborts getpriority() if the process is not present.
+This is not possible on older versions C<2.*>, and has a race
+condition anyway.
=head2 C<system()>
L<OS2::Process>.
When finding a program to run, Perl first asks the OS to look for executables
-on C<PATH>. If not found, it looks for a script with possible extensions
+on C<PATH> (OS/2 adds extension F<.exe> if no extension is present).
+If not found, it looks for a script with possible extensions
added in this order: no extension, F<.cmd>, F<.btm>,
F<.bat>, F<.pl>. If found, Perl checks the start of the file for magic
strings C<"#!"> and C<"extproc ">. If found, Perl uses the rest of the
extproc /bin/bash -x -c
-If F</bin/bash> is not found, and appending of executable extensions to
-F</bin/bash> does not help either, then Perl looks for an executable F<bash> on
+If F</bin/bash.exe> is not found, then Perl looks for an executable F<bash.exe> on
C<PATH>. If found in F<C:/emx.add/bin/bash.exe>, then the above system() is
translated to
given to system(). In particular, if no additional arguments are specified
on the "magic" first lines, then the limit on the depth is 4.
-If Perl finds that the found executable is of different type than the
-current session, it will start the new process in a separate session of
+If Perl finds that the found executable is of PM type when the
+current session is not, it will start the new process in a separate session of
necessary type. Call via C<OS2::Process> to disable this magic.
+B<WARNING>. Due to the described logic, you need to explicitly
+specify F<.com> extension if needed. Moreover, if the executable
+F<perl5.6.1> is requested, Perl will not look for F<perl5.6.1.exe>.
+[This may change in the future.]
+
=head2 C<extproc> on the first line
If the first chars of a Perl script are C<"extproc ">, this line is treated
Two additional extensions by Andreas Kaiser, C<OS2::UPM>, and
C<OS2::FTP>, are included into C<ILYAZ> directory, mirrored on CPAN.
+Other OS/2-related extensions are available too.
=head2 Prebuilt methods:
=item C<Cwd::change_drive(name)>
-chanes the "current" drive.
+changes the "current" drive.
=item C<Cwd::sys_is_absolute(name)>
=item C<Cwd::extLibpath([type])>
Get current value of extended library search path. If C<type> is
-present and I<true>, works with END_LIBPATH, otherwise with
-C<BEGIN_LIBPATH>.
+present and positive, works with C<END_LIBPATH>, if negative, works
+with C<LIBPATHSTRICT>, otherwise with C<BEGIN_LIBPATH>.
=item C<Cwd::extLibpath_set( path [, type ] )>
Set current value of extended library search path. If C<type> is
-present and I<true>, works with END_LIBPATH, otherwise with
-C<BEGIN_LIBPATH>.
+present and positive, works with <END_LIBPATH>, if negative, works
+with C<LIBPATHSTRICT>, otherwise with C<BEGIN_LIBPATH>.
=item C<OS2::Error(do_harderror,do_exception)>
Returns C<undef> if it was not called yet, otherwise bit 1 is
set if on the previous call do_harderror was enabled, bit
-2 is set if if on previous call do_exception was enabled.
+2 is set if on previous call do_exception was enabled.
This function enables/disables error popups associated with
hardware errors (Disk not ready etc.) and software exceptions.
See L<"Misfeatures"> for details.
+=item C<OS2::DLLname([how [, \&xsub]])>
+
+Gives the information about the Perl DLL or the DLL containing the C
+function bound to by C<&xsub>. The meaning of C<how> is: default (2):
+full name; 0: handle; 1: module name.
+
=back
(Note that some of these may be moved to different libraries -
=item $OS2::emx_rev
-same as _emx_rev of EMX, a string similar to C<0.9c>.
+numeric value is the same as _emx_rev of EMX, a string value the same
+as _emx_vprt (similar to C<0.9c>).
=item $OS2::emx_env
a number C<OS_MAJOR + 0.001 * OS_MINOR>.
+=item $OS2::is_aout
+
+true if the Perl library was compiled in AOUT format.
+
+=item $OS2::can_fork
+
+true if the current executable is an AOUT EMX executable, so Perl can
+fork. Do not use this, use the portable check for
+$Config::Config{dfork}.
+
+=item $OS2::nsyserror
+
+This variable (default is 1) controls whether to enforce the contents
+of $^E to start with C<SYS0003>-like id. If set to 0, then the string
+value of $^E is what is available from the OS/2 message file. (Some
+messages in this file have an C<SYS0003>-like id prepended, some not.)
+
=back
=head2 Misfeatures
=item *
-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
-the current pdksh.
+See L<"Text-mode filehandles">.
=item *
any function in the DLL, just the act of loading this DLL will reset your
flags. What is worse, the same compiler was used to compile some HOOK DLLs.
Given that HOOK dlls are executed in the context of I<all> the applications
-in the system, this means a complete unpredictablity of floating point
+in the system, this means a complete unpredictability of floating point
flags on systems using such HOOK DLLs. E.g., F<GAMESRVR.DLL> of B<DIVE>
origin changes the floating point flags on each write to the TTY of a VIO
(windowed text-mode) applications.
To circumvent this, Perl uses two hacks. They help against I<one> type of
damage only: FP flags changed when loading a DLL.
-One of the hacks is to disable floating point exceptions on startup (as
+One of the hacks is to disable floating point exceptions on Perl startup (as
is the default with EMX). This helps only with compile-time-linked DLLs
changing the flags before main() had a chance to be called.
shutdown will be automatically cancelled. Do not call C<perl_hmq_GET(1)>
unless you are going to process messages on an orderly basis.
+=item Treating errors reported by OS/2 API
+
+There are two principal conventions (it is useful to call them C<Dos*>
+and C<Win*> - though this part of the function signature is not always
+determined by the name of the API) of reporting the error conditions
+of OS/2 API. Most of C<Dos*> APIs report the error code as the result
+of the call (so 0 means success, and there are many types of errors).
+Most of C<Win*> API report success/fail via the result being
+C<TRUE>/C<FALSE>; to find the reason for the failure one should call
+WinGetLastError() API.
+
+Some C<Win*> entry points also overload a "meaningful" return value
+with the error indicator; having a 0 return value indicates an error.
+Yet some other C<Win*> entry points overload things even more, and 0
+return value may mean a successful call returning a valid value 0, as
+well as an error condition; in the case of a 0 return value one should
+call WinGetLastError() API to distinguish a successful call from a
+failing one.
+
+By convention, all the calls to OS/2 API should indicate their
+failures by resetting $^E. All the Perl-accessible functions which
+call OS/2 API may be broken into two classes: some die()s when an API
+error is encountered, the other report the error via a false return
+value (of course, this does not concern Perl-accessible functions
+which I<expect> a failure of the OS/2 API call, having some workarounds
+coded).
+
+Obviously, in the situation of the last type of the signature of an OS/2
+API, it is must more convenient for the users if the failure is
+indicated by die()ing: one does not need to check $^E to know that
+something went wrong. If, however, this solution is not desirable by
+some reason, the code in question should reset $^E to 0 before making
+this OS/2 API call, so that the caller of this Perl-accessible
+function has a chance to distinguish a success-but-0-return value from
+a failure. (One may return undef as an alternative way of reporting
+an error.)
+
+The macros to simplify this type of error propagation are
+
+=over
+
+=item C<CheckOSError(expr)>
+
+Returns true on error, sets $^E. Expects expr() be a call of
+C<Dos*>-style API.
+
+=item C<CheckWinError(expr)>
+
+Returns true on error, sets $^E. Expects expr() be a call of
+C<Win*>-style API.
+
+=item C<SaveWinError(expr)>
+
+Returns C<expr>, sets $^E from WinGetLastError() if C<expr> is false.
+
+=item C<SaveCroakWinError(expr,die,name1,name2)>
+
+Returns C<expr>, sets $^E from WinGetLastError() if C<expr> is false,
+and die()s if C<die> and $^E are true. The message to die is the
+concatenated strings C<name1> and C<name2>, separated by C<": "> from
+the contents of $^E.
+
+=item C<WinError_2_Perl_rc>
+
+Sets C<Perl_rc> to the return value of WinGetLastError().
+
+=item C<FillWinError>
+
+Sets C<Perl_rc> to the return value of WinGetLastError(), and sets $^E
+to the corresponding value.
+
+=item C<FillOSError(rc)>
+
+Sets C<Perl_rc> to C<rc>, and sets $^E to the corresponding value.
+
+=back
+
+=item Loading DLLs and ordinals in DLLs
+
+Some DLLs are only present in some versions of OS/2, or in some
+configurations of OS/2. Some exported entry points are present only
+in DLLs shipped with some versions of OS/2. If these DLLs and entry
+points were linked directly for a Perl executable/DLL or from a Perl
+extensions, this binary would work only with the specified
+versions/setups. Even if these entry points were not needed, the
+I<load> of the executable (or DLL) would fail.
+
+For example, many newer useful APIs are not present in OS/2 v2; many
+PM-related APIs require DLLs not available on floppy-boot setup.
+
+To make these calls fail I<only when the calls are executed>, one
+should call these API via a dynamic linking API. There is a subsystem
+in Perl to simplify such type of calls. A large number of entry
+points available for such linking is provided (see C<entries_ordinals>
+- and also C<PMWIN_entries> - in F<os2ish.h>). These ordinals can be
+accessed via the APIs:
+
+ CallORD(), DeclFuncByORD(), DeclVoidFuncByORD(),
+ DeclOSFuncByORD(), DeclWinFuncByORD(), AssignFuncPByORD(),
+ DeclWinFuncByORD_CACHE(), DeclWinFuncByORD_CACHE_survive(),
+ DeclWinFuncByORD_CACHE_resetError_survive(),
+ DeclWinFunc_CACHE(), DeclWinFunc_CACHE_resetError(),
+ DeclWinFunc_CACHE_survive(), DeclWinFunc_CACHE_resetError_survive()
+
+See the header files and the C code in the supplied OS/2-related
+modules for the details on usage of these functions.
+
+Some of these functions also combine dynaloading semantic with the
+error-propagation semantic discussed above.
+
=back
=head1 Perl flavors
a VIO window present, but not C<detach>ed (run C<help detach> for more info).
Very useful for extensions which use PM, like C<Perl/Tk> or C<OpenGL>.
+Note also that the differences between PM and VIO executables are only
+in the I<default> behaviour. One can start I<any> executable in
+I<any> kind of session by using the arguments C</fs>, C</pm> or
+C</win> switches of the command C<start> (of F<CMD.EXE> or a similar
+shell). Alternatively, one can use the numeric first argument of the
+C<system> Perl function (see L<OS2::Process>).
+
=head2 F<perl___.exe>
This is an C<omf>-style executable which is dynamically linked to
=head2 Why strange names?
Since Perl processes the C<#!>-line (cf.
-L<perlrun/DESCRIPTION>, L<perlrun/Switches>,
-L<perldiag/"Not a perl script">,
+L<perlrun/DESCRIPTION>, L<perlrun/Command Switches>,
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
but very quick and convenient-to-users "hard" dynamic linking used by OS/2.
There are two distinctive features of the dyna-linking model of OS/2:
-all the references to external functions are resolved at the compile time;
-there is no runtime fixup of the DLLs after they are loaded into memory.
+first, all the references to external functions are resolved at the compile time;
+second, there is no runtime fixup of the DLLs after they are loaded into memory.
The first feature is an enormous advantage over other models: it avoids
conflicts when several DLLs used by an application export entries with
the same name. In such cases "other" models of dyna-linking just choose
processes have these sections loaded at same addresses, and no fixup
of internal links inside the F<.EXE> is needed.
-Since DLLs may be loaded at run time, to have the same mechanism for for DLLs
+Since DLLs may be loaded at run time, to have the same mechanism for DLLs
one needs to have the address range of I<any of the loaded> DLLs in the
system to be available I<in all the processes> which did not load a particular
DLL yet. This is why the DLLs are mapped to the shared memory region.
Here we list major changes which could make you by surprise.
+=head2 Text-mode filehandles
+
+Starting from version 5.8, Perl uses a builtin translation layer for
+text-mode files. This replaces the efficient well-tested EMX layer by
+some code which should be best characterized as a "quick hack".
+
+In addition to possible bugs and an inability to follow changes to the
+translation policy with off/on switches of TERMIO translation, this
+introduces a serious incompatible change: before sysread() on
+text-mode filehandles would go through the translation layer, now it
+would not.
+
=head2 Priorities
C<setpriority> and C<getpriority> are not compatible with earlier
ports by Andreas Kaiser. See C<"setpriority, getpriority">.
-=head2 DLL name mangling
+=head2 DLL name mangling: pre 5.6.2
With the release 5.003_01 the dynamically loadable libraries
should be rebuilt when a different version of Perl is compiled. In particular,
=back
+=head2 DLL name mangling: 5.6.2 and beyond
+
+In fact mangling of I<extension> DLLs was done due to misunderstanding
+of the OS/2 dynaloading model. OS/2 (effectively) maintains two
+different tables of loaded DLL:
+
+=over
+
+=item Global DLLs
+
+those loaded by the base name from C<LIBPATH>; including those
+associated at link time;
+
+=item specific DLLs
+
+loaded by the full name.
+
+=back
+
+When resolving a request for a global DLL, the table of already-loaded
+specific DLLs is (effectively) ignored; moreover, specific DLLs are
+I<always> loaded from the prescribed path.
+
+There is/was a minor twist which makes this scheme fragile: what to do
+with DLLs loaded from
+
+=over
+
+=item C<BEGINLIBPATH> and C<ENDLIBPATH>
+
+(which depend on the process)
+
+=item F<.> from C<LIBPATH>
+
+which I<effectively> depends on the process (although C<LIBPATH> is the
+same for all the processes).
+
+=back
+
+Unless C<LIBPATHSTRICT> is set to C<T> (and the kernel is after
+2000/09/01), such DLLs are considered to be global. When loading a
+global DLL it is first looked in the table of already-loaded global
+DLLs. Because of this the fact that one executable loaded a DLL from
+C<BEGINLIBPATH> and C<ENDLIBPATH>, or F<.> from C<LIBPATH> may affect
+I<which> DLL is loaded when I<another> executable requests a DLL with
+the same name. I<This> is the reason for version-specific mangling of
+the DLL name for perl DLL.
+
+Since the Perl extension DLLs are always loaded with the full path,
+there is no need to mangle their names in a version-specific ways:
+their directory already reflects the corresponding version of perl,
+and @INC takes into account binary compatibility with older version.
+Starting from C<5.6.2> the name mangling scheme is fixed to be the
+same as for Perl 5.005_53 (same as in a popular binary release). Thus
+new Perls will be able to I<resolve the names> of old extension DLLs
+if @INC allows finding their directories.
+
+However, this still does not guarantee that these DLL may be loaded.
+The reason is the mangling of the name of the I<Perl DLL>. And since
+the extension DLLs link with the Perl DLL, extension DLLs for older
+versions would load an older Perl DLL, and would most probably
+segfault (since the data in this DLL is not properly initialized).
+
+There is a partial workaround (which can be made complete with newer
+OS/2 kernels): create a forwarder DLL with the same name as the DLL of
+the older version of Perl, which forwards the entry points to the
+newer Perl's DLL. Make this DLL accessible on (say) the C<BEGINLIBPATH> of
+the new Perl executable. When the new executable accesses old Perl's
+extension DLLs, they would request the old Perl's DLL by name, get the
+forwarder instead, so effectively will link with the currently running
+(new) Perl DLL.
+
+This may break in two ways:
+
+=over
+
+=item *
+
+Old perl executable is started when a new executable is running has
+loaded an extension compiled for the old executable (ouph!). In this
+case the old executable will get a forwarder DLL instead of the old
+perl DLL, so would link with the new perl DLL. While not directly
+fatal, it will behave the same as new executable. This beats the whole
+purpose of explicitly starting an old executable.
+
+=item *
+
+A new executable loads an extension compiled for the old executable
+when an old perl executable is running. In this case the extension
+will not pick up the forwarder - with fatal results.
+
+=back
+
+With support for C<LIBPATHSTRICT> this may be circumvented - unless
+one of DLLs is started from F<.> from C<LIBPATH> (I do not know
+whether C<LIBPATHSTRICT> affects this case).
+
+B<REMARK>. Unless newer kernels allow F<.> in C<BEGINLIBPATH> (older
+do not), this mess cannot be completely cleaned. (It turns out that
+as of the beginning of 2002, F<.> is not allowed, but F<.\.> is - and
+it has the same effect.)
+
+
+B<REMARK>. C<LIBPATHSTRICT>, C<BEGINLIBPATH> and C<ENDLIBPATH> are
+not environment variables, although F<cmd.exe> emulates them on C<SET
+...> lines. From Perl they may be accessed by
+L<Cwd::extLibpath|/Cwd::extLibpath([type])> and
+L<Cwd::extLibpath_set|/Cwd::extLibpath_set( path [, type ] )>.
+
+=head2 DLL forwarder generation
+
+Assume that the old DLL is named F<perlE0AC.dll> (as is one for
+5.005_53), and the new version is 5.6.1. Create a file
+F<perl5shim.def-leader> with
+
+ LIBRARY 'perlE0AC' INITINSTANCE TERMINSTANCE
+ DESCRIPTION '@#perl5-porters@perl.org:5.006001#@ Perl module for 5.00553 -> Perl 5.6.1 forwarder'
+ CODE LOADONCALL
+ DATA LOADONCALL NONSHARED MULTIPLE
+ EXPORTS
+
+modifying the versions/names as needed. Run
+
+ perl -wnle "next if 0../EXPORTS/; print qq( \"$1\") if /\"(\w+)\"/" perl5.def >lst
+
+in the Perl build directory (to make the DLL smaller replace perl5.def
+with the definition file for the older version of Perl if present).
+
+ cat perl5shim.def-leader lst >perl5shim.def
+ gcc -Zomf -Zdll -o perlE0AC.dll perl5shim.def -s -llibperl
+
+(ignore multiple C<warning L4085>).
+
=head2 Threading
As of release 5.003_01 perl is linked to multithreaded C RTL
with F<cmd.exe> as a shell, thus I picked up C<sh.exe>. This 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 L<"Prerequisites">).
+(see L</Prerequisites>).
B<Disadvantages:> currently F<sh.exe> of pdksh calls external programs
via fork()/exec(), and there is I<no> functioning exec() on
cannot test it.
For the details of the current situation with calling external programs,
-see L<Starting OS/2 (and DOS) programs under Perl>. Set us mention a couple
+see L<Starting OSE<sol>2 (and DOS) programs under Perl>. Set us mention a couple
of features:
=over 4
=item C<COND_WAIT>
-may have a race condition. Needs a reimplementation (in terms of chaining
-waiting threads, with the linked list stored in per-thread structure?).
+may have a race condition (but probably does not due to edge-triggered
+nature of OS/2 Event semaphores). (Needs a reimplementation (in terms of chaining
+waiting threads, with the linked list stored in per-thread structure?)?)
=item F<os2.c>
Note that these problems should not discourage experimenting, since they
have a low probability of affecting small programs.
+=head1 BUGS
+
+This description is not updated often (since 5.6.1?), see F<./os2/Changes>
+for more info.
+
=cut
OS/2 extensions
=head1 AUTHOR
-Ilya Zakharevich, ilya@math.ohio-state.edu
+Ilya Zakharevich, cpan@ilyaz.org
=head1 SEE ALSO
https://perl5.git.perl.org / perl5.git / blobdiff