=head1 NAME
-perlwin32 - Perl under WindowsNT [XXX and perhaps under Windows95]
+perlwin32 - Perl under Win32
=head1 SYNOPSIS
-These are instructions for building Perl under WindowsNT (versions
-3.51 or 4.0), using Visual C++.
+These are instructions for building Perl under Windows NT (versions
+3.51 or 4.0). Currently, this port is reported to build under
+Windows95 using the 4DOS shell--the default shell that infests
+Windows95 may not work fully (but see below). Note that this caveat
+is only about B<building> perl. Once built, you should be able to
+B<use> it on either Win32 platform (modulo the problems arising from
+the inferior command shell).
=head1 DESCRIPTION
-Before you start, you should glance through the README file found
+Before you start, you should glance through the README file
found in the top-level directory where the Perl distribution
was extracted. Make sure you read and understand the terms under
which this software is being distributed.
-Make sure you read the L<BUGS AND CAVEATS> section below for the
+Also make sure you read L<BUGS AND CAVEATS> below for the
known limitations of this port.
The INSTALL file in the perl top-level has much information that is
particular, you can safely ignore any information that talks about
"Configure".
-You should probably also read the README.os2 file, which gives a
-different set of rules to build a Perl that will work on Win32
-platforms. That method will probably enable you to build a more
-Unix-compatible perl, but you will also need to download and use
-various other support software described in that file.
+You may also want to look at two other options for building
+a perl that will work on Windows NT: the README.cygwin and
+README.os2 files, which each give a different set of rules to build
+a Perl that will work on Win32 platforms. Those two methods will
+probably enable you to build a more Unix-compatible perl, but you
+will also need to download and use various other build-time and
+run-time support software described in those files.
This set of instructions is meant to describe a so-called "native"
port of Perl to Win32 platforms. The resulting Perl requires no
additional software to run (other than what came with your operating
-system). Currently, this port is only capable of using Microsoft's
-Visual C++ compiler. The ultimate goal is to support the other major
-compilers that can be used on the platforms.
+system). Currently, this port is capable of using one of the
+following compilers:
+
+ Borland C++ version 5.02 or later
+ Microsoft Visual C++ version 4.2 or later
+ Mingw32 with EGCS versions 1.0.2, 1.1
+ Mingw32 with GCC version 2.8.1
+
+The last two of these are high quality freeware compilers. Support
+for them is still experimental.
+
+This port currently supports MakeMaker (the set of modules that
+is used to build extensions to perl). Therefore, you should be
+able to build and install most extensions found in the CPAN sites.
+See L<Usage Hints> below for general hints about this.
=head2 Setting Up
=over 4
+=item Command Shell
+
+Use the default "cmd" shell that comes with NT. Some versions of the
+popular 4DOS/NT shell have incompatibilities that may cause you trouble.
+If the build fails under that shell, try building again with the cmd
+shell. The nmake Makefile also has known incompatibilites with the
+"command.com" shell that comes with Windows95.
+
+However, there have been reports of successful build attempts using
+4DOS/NT version 6.01 under Windows95, using dmake, but your mileage
+may vary. There is also some basic support for building using dmake
+under command.com. Nevertheless, if building under command.com
+doesn't work, try 4DOS/NT.
+
+The surest way to build it is on Windows NT, using the cmd shell.
+
+Make sure the path to the build directory does not contain spaces. The
+build usually works in this circumstance, but some tests will fail.
+
+=item Borland C++
+
+If you are using the Borland compiler, you will need dmake, a freely
+available make that has very nice macro features and parallelability.
+(The make that Borland supplies is seriously crippled, and will not
+work for MakeMaker builds.)
+
+A port of dmake for win32 platforms is available from:
+
+ ftp://ftp.linux.activestate.com/pub/staff/gsar/dmake-4.1-win32.zip
+
+Fetch and install dmake somewhere on your path (follow the instructions
+in the README.NOW file).
+
+=item Microsoft Visual C++
+
+The nmake that comes with Visual C++ will suffice for building.
+You will need to run the VCVARS32.BAT file usually found somewhere
+like C:\MSDEV4.2\BIN. This will set your build environment.
+
+You can also use dmake to build using Visual C++, provided:
+you set OSRELEASE to "microsft" (or whatever the directory name
+under which the Visual C dmake configuration lives) in your environment,
+and edit win32/config.vc to change "make=nmake" into "make=dmake". The
+latter step is only essential if you want to use dmake as your default
+make for building extensions using MakeMaker.
+
+=item Mingw32 with EGCS or GCC
+
+ECGS binaries can be downloaded from:
+
+ ftp://ftp.xraylith.wisc.edu/pub/khan/gnu-win32/mingw32/
+
+GCC-2.8.1 binaries are available from:
+
+ http://agnes.dida.physik.uni-essen.de/~janjaap/mingw32/
+
+You only need either one of those, not both. Both bundles come with
+Mingw32 libraries and headers. While both of them work to build perl,
+the EGCS binaries are currently favored by the maintainers, since they
+come with more up-to-date Mingw32 libraries.
+
+Make sure you install the binaries as indicated in the web sites
+above. You will need to set up a few environment variables (usually
+run from a batch file).
+
+You also need dmake. See L</"Borland C++"> above on how to get it.
+
+=back
+
+=head2 Building
+
+=over 4
+
=item *
-Use the default "cmd" shell that comes with NT. In particular, do
-*not* use the 4DOS/NT shell. The Makefile has commands that are not
-compatible with that shell.
+Make sure you are in the "win32" subdirectory under the perl toplevel.
+This directory contains a "Makefile" that will work with
+versions of nmake that come with Visual C++, and a dmake "makefile.mk"
+that will work for all supported compilers. The defaults in the dmake
+makefile are setup to build using the Borland compiler.
=item *
-Run the VCVARS32.BAT file usually found somewhere like C:\MSDEV4.2\BIN.
-This will set your build environment.
+Edit the makefile.mk (or Makefile, if using nmake) and change the values
+of INST_DRV and INST_TOP. You can also enable various build
+flags.
+
+Beginning with version 5.005, there is experimental support for building
+a perl interpreter that supports the Perl Object abstraction (courtesy
+ActiveState Tool Corp.) PERL_OBJECT uses C++, and the binaries are
+therefore incompatible with the regular C build. However, the
+PERL_OBJECT build does provide something called the C-API, for linking
+it with extensions that won't compile under PERL_OBJECT. Using the C_API
+is typically requested through:
+
+ perl Makefile.PL CAPI=TRUE
+
+PERL_OBJECT requires VC++ 5.0 (Service Pack 3 recommended) or later. It
+is not yet supported under GCC or EGCS. WARNING: Binaries built with
+PERL_OBJECT enabled are B<not> compatible with binaries built without.
+Perl installs PERL_OBJECT binaries under a distinct architecture name,
+so they B<can> coexist, though.
+
+Beginning with version 5.005, there is experimental support for building
+a perl interpreter that is capable of native threading. Binaries built
+with thread support enabled are also incompatible with the vanilla C
+build. WARNING: Binaries built with threads enabled are B<not> compatible
+with binaries built without. Perl installs threads enabled binaries under
+a distinct architecture name, so they B<can> coexist, though.
+
+At the present time, you cannot enable both threading and PERL_OBJECT.
+You can get only one of them in a Perl interpreter.
+
+If you have either the source or a library that contains des_fcrypt(),
+enable the appropriate option in the makefile. des_fcrypt() is not
+bundled with the distribution due to US Government restrictions
+on the export of cryptographic software. Nevertheless, this routine
+is part of the "libdes" library (written by Ed Young) which is widely
+available worldwide, usually along with SSLeay (for example:
+"ftp://fractal.mta.ca/pub/crypto/SSLeay/DES/"). Set CRYPT_SRC to the
+name of the file that implements des_fcrypt(). Alternatively, if
+you have built a library that contains des_fcrypt(), you can set
+CRYPT_LIB to point to the library name. The location above contains
+many versions of the "libdes" library, all with slightly different
+implementations of des_fcrypt(). Older versions have a single,
+self-contained file (fcrypt.c) that implements crypt(), so they may be
+easier to use. A patch against the fcrypt.c found in libdes-3.06 is
+in des_fcrypt.patch.
+
+Perl will also build without des_fcrypt(), but the crypt() builtin will
+fail at run time.
+
+You will also have to make sure CCHOME points to wherever you installed
+your compiler.
+
+The default value for CCHOME in the makefiles for Visual C++
+may not be correct for some versions. Make sure the default exists
+and is valid.
+
+Other options are explained in the makefiles. Be sure to read the
+instructions carefully.
=item *
-Depending on how you extracted the distribution, you have to make sure
-all the files are writable by you. The easiest way to make sure of
-this is to execute:
+Type "dmake" (or "nmake" if you are using that make).
+
+This should build everything. Specifically, it will create perl.exe,
+perl.dll (or perl56.dll), and perlglob.exe at the perl toplevel, and
+various other extension dll's under the lib\auto directory. If the build
+fails for any reason, make sure you have done the previous steps correctly.
- attrib -R *.* /S
+The build process may produce "harmless" compiler warnings (more or
+less copiously, depending on how picky your compiler gets). The
+maintainers are aware of these warnings, thankyouverymuch. :)
-from the perl toplevel directory. You don't I<have> to do this if you
-used the right tools to extract the files in the standard distribution,
-but it doesn't hurt to do so.
+When building using Visual C++, a perl95.exe will also get built. This
+executable is only needed on Windows95, and should be used instead of
+perl.exe, and then only if you want sockets to work properly on Windows95.
+This is necessitated by a bug in the Microsoft C Runtime that cannot be
+worked around in the "normal" perl.exe. perl95.exe gets built with its
+own private copy of the C Runtime that is not accessible to extensions
+(which see the DLL version of the CRT). Be aware, therefore, that this
+perl95.exe will have esoteric problems with extensions like perl/Tk that
+themselves use the C Runtime heavily, or want to free() pointers
+malloc()-ed by perl.
+
+You can avoid the perl95.exe problems completely if you either enable
+USE_PERLCRT with Visual C++, or use Borland C++ for building perl. In
+those cases, perl95.exe is not needed and will not be built.
=back
-=head2 Building and Installation
+=head2 Testing
-=over 4
+Type "dmake test" (or "nmake test"). This will run most of the tests from
+the testsuite (many tests will be skipped, and but no test should fail).
-=item *
+If some tests do fail, it may be because you are using a different command
+shell than the native "cmd.exe", or because you are building from a path
+that contains spaces. So don't do that.
-The "win32" directory contains *.mak files for use with the NMAKE that
-comes with Visual C++ ver. 4.0 and above. If you wish to build perl
-using Visual C++ versions between 2.0 and 4.0, do the following three
-additional steps (these three steps are not required if you are
-using Visual C++ versions 4.0 and above):
+If you are running the tests from a emacs shell window, you may see
+failures in op/stat.t. Run "dmake test-notty" in that case.
-=over 8
+If you're using the Borland compiler, you may see a failure in op/taint.t
+arising from the inability to find the Borland Runtime DLLs on the system
+default path. You will need to copy the DLLs reported by the messages
+from where Borland chose to install it, into the Windows system directory
+(usually somewhere like C:\WINNT\SYSTEM32), and rerun the test.
-=item 1.
+The Visual C runtime apparently has a bug that causes posix.t to fail
+test#2. This usually happens only if you extracted the files in text
+mode. Enable the USE_PERLCRT option in the Makefile to fix this bug.
-Overwrite the *.mak files in the win32 subdirectory with the versions
-in the win32\VC-2.0 directory. (The only difference in those makefiles
-is in how the $(INCLUDE) variable is handled--VC 2.0 NMAKE does not
-grok a path list in $(INCLUDE)).
+Please report any other failures as described under L<BUGS AND CAVEATS>.
-=item 2.
+=head2 Installation
-Reset your INCLUDE environment variable to the MSVC include directory.
+Type "dmake install" (or "nmake install"). This will put the newly
+built perl and the libraries under whatever C<INST_TOP> points to in the
+Makefile. It will also install the pod documentation under
+C<$INST_TOP\$VERSION\lib\pod> and HTML versions of the same under
+C<$INST_TOP\$VERSION\lib\pod\html>. To use the Perl you just installed,
+you will need to add two components to your PATH environment variable,
+C<$INST_TOP\$VERSION\bin>, and C<$INST_TOP\$VERSION\bin\$ARCHNAME>.
For example:
- set INCLUDE=E:\MSVC20\INCLUDE
+ set PATH c:\perl\5.005\bin;c:\perl\5.005\bin\MSWin32-x86;%PATH%
+
-This must have only one directory (a list of directories will not work).
-VCVARS32.BAT may put multiple locations in there, which is why this step
-is required.
+=head2 Usage Hints
-=item 3.
+=over 4
-Apply the patch found in win32\VC-2.0\vc2.patch, like so:
+=item Environment Variables
- cd win32
- patch -p2 -N < VC-2.0\vc2.patch
+The installation paths that you set during the build get compiled
+into perl, so you don't have to do anything additional to start
+using that perl (except add its location to your PATH variable).
-You may have to edit win32\win32.c manually if you don't have GNU patch.
+If you put extensions in unusual places, you can set PERL5LIB
+to a list of paths separated by semicolons where you want perl
+to look for libraries. Look for descriptions of other environment
+variables you can set in L<perlrun>.
-=back
+You can also control the shell that perl uses to run system() and
+backtick commands via PERL5SHELL. See L<perlrun>.
-=item *
+Perl does not depend on the registry, but it can look up certain default
+values if you choose to put them there. Perl attempts to read entries from
+C<HKEY_CURRENT_USER\Software\Perl> and C<HKEY_LOCAL_MACHINE\Software\Perl>.
+Entries in the former override entries in the latter. One or more of the
+following entries (of type REG_SZ or REG_EXPAND_SZ) may be set:
-Make sure you are in the "win32" subdirectory under the perl toplevel.
+ lib-$] version-specific path to add to @INC
+ lib path to add to @INC
+ sitelib-$] version-specific path to add to @INC
+ sitelib path to add to @INC
+ PERL* fallback for all %ENV lookups that begin with "PERL"
-=item *
+Note the C<$]> in the above is not literal. Substitute whatever version
+of perl you want to honor that entry, e.g. C<5.00502>. Paths must be
+separated with semicolons, as usual on win32.
-Type "nmake" while in the "win32" subdirectory. This should build
-everything. Specifically, it will create perl.exe, perl.dll, and
-perlglob.exe at the perl toplevel, and various other extension dll's
-under the lib\auto directory. If the make fails for any reason, make
-sure you have done the previous steps correctly.
+=item File Globbing
-=item *
+By default, perl spawns an external program to do file globbing.
+The install process installs both a perlglob.exe and a perlglob.bat
+that perl can use for this purpose. Note that with the default
+installation, perlglob.exe will be found by the system before
+perlglob.bat.
-Type "nmake install". This will put the newly built perl and the
-libraries under C:\PERL. If you want to alter this location, to say,
-D:\FOO\PERL, you will have to say:
+perlglob.exe relies on the argv expansion done by the C Runtime of
+the particular compiler you used, and therefore behaves very
+differently depending on the Runtime used to build it. To preserve
+compatiblity, perlglob.bat (a perl script that can be used portably)
+is installed. Besides being portable, perlglob.bat also offers
+enhanced globbing functionality.
- nmake install INST_TOP=D:\FOO\PERL
+If you want perl to use perlglob.bat instead of perlglob.exe, just
+delete perlglob.exe from the install location (or move it somewhere
+perl cannot find). Using File::DosGlob.pm (which implements the core
+functionality of perlglob.bat) to override the internal CORE::glob()
+works about 10 times faster than spawing perlglob.exe, and you should
+take this approach when writing new modules. See File::DosGlob for
+details.
-instead. To use the Perl you just installed, make sure you set your
-PATH environment variable to C:\PERL\BIN (or D:\FOO\PERL\BIN).
+=item Using perl from the command line
-=back
+If you are accustomed to using perl from various command-line
+shells found in UNIX environments, you will be less than pleased
+with what Windows NT offers by way of a command shell.
-=head2 Testing
+The crucial thing to understand about the "cmd" shell (which is
+the default on Windows NT) is that it does not do any wildcard
+expansions of command-line arguments (so wildcards need not be
+quoted). It also provides only rudimentary quoting. The only
+(useful) quote character is the double quote ("). It can be used to
+protect spaces in arguments and other special characters. The
+Windows NT documentation has almost no description of how the
+quoting rules are implemented, but here are some general observations
+based on experiments: The shell breaks arguments at spaces and
+passes them to programs in argc/argv. Doublequotes can be used
+to prevent arguments with spaces in them from being split up.
+You can put a double quote in an argument by escaping it with
+a backslash and enclosing the whole argument within double quotes.
+The backslash and the pair of double quotes surrounding the
+argument will be stripped by the shell.
-Type "nmake test". This will run most of the tests from the
-testsuite (many tests will be skipped, and some tests will fail).
-Most failures are due to UNIXisms in the standard perl testsuite.
+The file redirection characters "<", ">", and "|" cannot be quoted
+by double quotes (there are probably more such). Single quotes
+will protect those three file redirection characters, but the
+single quotes don't get stripped by the shell (just to make this
+type of quoting completely useless). The caret "^" has also
+been observed to behave as a quoting character (and doesn't get
+stripped by the shell also).
-To get a more detailed breakdown of the tests that failed, say:
+Here are some examples of usage of the "cmd" shell:
- cd ..\t
- .\perl harness
+This prints two doublequotes:
-This should produce a summary very similar to the following:
+ perl -e "print '\"\"' "
- Failed Test Status Wstat Total Fail Failed List of failed
- ------------------------------------------------------------------------------
- io/fs.t 26 16 61.54% 1-5, 7-11, 16-18, 23-25
- io/tell.t 13 1 7.69% 10
- lib/anydbm.t 12 1 8.33% 2
- lib/findbin.t 1 1 100.00% 1
- lib/sdbm.t 12 1 8.33% 2
- op/mkdir.t 7 2 28.57% 3, 7
- op/runlevel.t 8 1 12.50% 4
- op/stat.t 56 3 5.36% 3-4, 20
- op/taint.t 98 20 20.41% 1-6, 14, 16, 19-21, 24, 26, 35-3
- pragma/locale.t 98 40 40.82% 1, 13-14, 21-27, 33, 39, 45-53,
- Failed 10/149 test scripts, 93.29% okay. 86/3506 subtests failed, 97.55% okay.
+This does the same:
-Check if any additional tests other than the ones shown here
-failed. The standard testsuite will ultimately be modified so
-that the testsuite avoids running irrelevant tests on Win32.
+ perl -e "print \"\\\"\\\"\" "
-=head1 BUGS AND CAVEATS
+This prints "bar" and writes "foo" to the file "blurch":
+
+ perl -e "print 'foo'; print STDERR 'bar'" > blurch
+
+This prints "foo" ("bar" disappears into nowhereland):
+
+ perl -e "print 'foo'; print STDERR 'bar'" 2> nul
+
+This prints "bar" and writes "foo" into the file "blurch":
+
+ perl -e "print 'foo'; print STDERR 'bar'" 1> blurch
+
+This pipes "foo" to the "less" pager and prints "bar" on the console:
+
+ perl -e "print 'foo'; print STDERR 'bar'" | less
+
+This pipes "foo\nbar\n" to the less pager:
+
+ perl -le "print 'foo'; print STDERR 'bar'" 2>&1 | less
+
+This pipes "foo" to the pager and writes "bar" in the file "blurch":
+
+ perl -e "print 'foo'; print STDERR 'bar'" 2> blurch | less
+
+
+Discovering the usefulness of the "command.com" shell on Windows95
+is left as an exercise to the reader :)
+
+=item Building Extensions
+
+The Comprehensive Perl Archive Network (CPAN) offers a wealth
+of extensions, some of which require a C compiler to build.
+Look in http://www.perl.com/ for more information on CPAN.
+
+Most extensions (whether they require a C compiler or not) can
+be built, tested and installed with the standard mantra:
+
+ perl Makefile.PL
+ $MAKE
+ $MAKE test
+ $MAKE install
+
+where $MAKE is whatever 'make' program you have configured perl to
+use. Use "perl -V:make" to find out what this is. Some extensions
+may not provide a testsuite (so "$MAKE test" may not do anything, or
+fail), but most serious ones do.
+
+It is important that you use a supported 'make' program, and
+ensure Config.pm knows about it. If you don't have nmake, you can
+either get dmake from the location mentioned earlier, or get an
+old version of nmake reportedly available from:
+
+ ftp://ftp.microsoft.com/Softlib/MSLFILES/nmake15.exe
+
+Another option is to use the make written in Perl, available from
+CPAN:
+
+ http://www.perl.com/CPAN/authors/id/NI-S/Make-0.03.tar.gz
+
+Note that MakeMaker actually emits makefiles with different syntax
+depending on what 'make' it thinks you are using. Therefore, it is
+important that one of the following values appears in Config.pm:
+
+ make='nmake' # MakeMaker emits nmake syntax
+ make='dmake' # MakeMaker emits dmake syntax
+ any other value # MakeMaker emits generic make syntax
+ (e.g GNU make, or Perl make)
+
+If the value doesn't match the 'make' program you want to use,
+edit Config.pm to fix it.
+
+If a module implements XSUBs, you will need one of the supported
+C compilers. You must make sure you have set up the environment for
+the compiler for command-line compilation.
+
+If a module does not build for some reason, look carefully for
+why it failed, and report problems to the module author. If
+it looks like the extension building support is at fault, report
+that with full details of how the build failed using the perlbug
+utility.
+
+=item Command-line Wildcard Expansion
+
+The default command shells on DOS descendant operating systems (such
+as they are) usually do not expand wildcard arguments supplied to
+programs. They consider it the application's job to handle that.
+This is commonly achieved by linking the application (in our case,
+perl) with startup code that the C runtime libraries usually provide.
+However, doing that results in incompatible perl versions (since the
+behavior of the argv expansion code differs depending on the
+compiler, and it is even buggy on some compilers). Besides, it may
+be a source of frustration if you use such a perl binary with an
+alternate shell that *does* expand wildcards.
-This is still very much an experimental port, and should be considered
-alpha quality software. You can expect changes in virtually all of
-these areas: build process, installation structure, supported
-utilities/modules, and supported perl functionality. Specifically,
-functionality that supports the Win32 environment may be ultimately
-be supported as either core modules or extensions.
+Instead, the following solution works rather well. The nice things
+about it: 1) you can start using it right away 2) it is more powerful,
+because it will do the right thing with a pattern like */*/*.c
+3) you can decide whether you do/don't want to use it 4) you can
+extend the method to add any customizations (or even entirely
+different kinds of wildcard expansion).
-Many tests from the standard testsuite either fail or produce different
-results under this port. Most of the problems fall under one of these
-categories
+ C:\> copy con c:\perl\lib\Wild.pm
+ # Wild.pm - emulate shell @ARGV expansion on shells that don't
+ use File::DosGlob;
+ @ARGV = map {
+ my @g = File::DosGlob::glob($_) if /[*?]/;
+ @g ? @g : $_;
+ } @ARGV;
+ 1;
+ ^Z
+ C:\> set PERL5OPT=-MWild
+ C:\> perl -le "for (@ARGV) { print }" */*/perl*.c
+ p4view/perl/perl.c
+ p4view/perl/perlio.c
+ p4view/perl/perly.c
+ perl5.005/win32/perlglob.c
+ perl5.005/win32/perllib.c
+ perl5.005/win32/perlglob.c
+ perl5.005/win32/perllib.c
+ perl5.005/win32/perlglob.c
+ perl5.005/win32/perllib.c
+
+Note there are two distinct steps there: 1) You'll have to create
+Wild.pm and put it in your perl lib directory. 2) You'll need to
+set the PERL5OPT environment variable. If you want argv expansion
+to be the default, just set PERL5OPT in your default startup
+environment.
+
+If you are using the Visual C compiler, you can get the C runtime's
+command line wildcard expansion built into perl binary. The resulting
+binary will always expand unquoted command lines, which may not be
+what you want if you use a shell that does that for you. The expansion
+done is also somewhat less powerful than the approach suggested above.
+
+=item Win32 Specific Extensions
+
+A number of extensions specific to the Win32 platform are available
+from CPAN. You may find that many of these extensions are meant to
+be used under the Activeware port of Perl, which used to be the only
+native port for the Win32 platform. Since the Activeware port does not
+have adequate support for Perl's extension building tools, these
+extensions typically do not support those tools either, and therefore
+cannot be built using the generic steps shown in the previous section.
+
+To ensure smooth transitioning of existing code that uses the
+ActiveState port, there is a bundle of Win32 extensions that contains
+all of the ActiveState extensions and most other Win32 extensions from
+CPAN in source form, along with many added bugfixes, and with MakeMaker
+support. This bundle is available at:
+
+ http://www.perl.com/CPAN/authors/id/GSAR/libwin32-0.14.zip
+
+See the README in that distribution for building and installation
+instructions. Look for later versions that may be available at the
+same location.
+
+=item Running Perl Scripts
+
+Perl scripts on UNIX use the "#!" (a.k.a "shebang") line to
+indicate to the OS that it should execute the file using perl.
+Win32 has no comparable means to indicate arbitrary files are
+executables.
+
+Instead, all available methods to execute plain text files on
+Win32 rely on the file "extension". There are three methods
+to use this to execute perl scripts:
+
+=over 8
+
+=item 1
+
+There is a facility called "file extension associations" that will
+work in Windows NT 4.0. This can be manipulated via the two
+commands "assoc" and "ftype" that come standard with Windows NT
+4.0. Type "ftype /?" for a complete example of how to set this
+up for perl scripts (Say what? You thought Windows NT wasn't
+perl-ready? :).
+
+=item 2
+
+Since file associations don't work everywhere, and there are
+reportedly bugs with file associations where it does work, the
+old method of wrapping the perl script to make it look like a
+regular batch file to the OS, may be used. The install process
+makes available the "pl2bat.bat" script which can be used to wrap
+perl scripts into batch files. For example:
+
+ pl2bat foo.pl
+
+will create the file "FOO.BAT". Note "pl2bat" strips any
+.pl suffix and adds a .bat suffix to the generated file.
+
+If you use the 4DOS/NT or similar command shell, note that
+"pl2bat" uses the "%*" variable in the generated batch file to
+refer to all the command line arguments, so you may need to make
+sure that construct works in batch files. As of this writing,
+4DOS/NT users will need a "ParameterChar = *" statement in their
+4NT.INI file, or will need to execute "setdos /p*" in the 4DOS/NT
+startup file to enable this to work.
+
+=item 3
+
+Using "pl2bat" has a few problems: the file name gets changed,
+so scripts that rely on C<$0> to find what they must do may not
+run properly; running "pl2bat" replicates the contents of the
+original script, and so this process can be maintenance intensive
+if the originals get updated often. A different approach that
+avoids both problems is possible.
+
+A script called "runperl.bat" is available that can be copied
+to any filename (along with the .bat suffix). For example,
+if you call it "foo.bat", it will run the file "foo" when it is
+executed. Since you can run batch files on Win32 platforms simply
+by typing the name (without the extension), this effectively
+runs the file "foo", when you type either "foo" or "foo.bat".
+With this method, "foo.bat" can even be in a different location
+than the file "foo", as long as "foo" is available somewhere on
+the PATH. If your scripts are on a filesystem that allows symbolic
+links, you can even avoid copying "runperl.bat".
+
+Here's a diversion: copy "runperl.bat" to "runperl", and type
+"runperl". Explain the observed behavior, or lack thereof. :)
+Hint: .gnidnats llits er'uoy fi ,"lrepnur" eteled :tniH
+
+=back
+
+=item Miscellaneous Things
+
+A full set of HTML documentation is installed, so you should be
+able to use it if you have a web browser installed on your
+system.
+
+C<perldoc> is also a useful tool for browsing information contained
+in the documentation, especially in conjunction with a pager
+like C<less> (recent versions of which have Win32 support). You may
+have to set the PAGER environment variable to use a specific pager.
+"perldoc -f foo" will print information about the perl operator
+"foo".
+
+If you find bugs in perl, you can run C<perlbug> to create a
+bug report (you may have to send it manually if C<perlbug> cannot
+find a mailer on your system).
+
+=back
+
+=head1 BUGS AND CAVEATS
+
+An effort has been made to ensure that the DLLs produced by the two
+supported compilers are compatible with each other (despite the
+best efforts of the compiler vendors). Extension binaries produced
+by one compiler should also coexist with a perl binary built by
+a different compiler. In order to accomplish this, PERL.DLL provides
+a layer of runtime code that uses the C Runtime that perl was compiled
+with. Extensions which include "perl.h" will transparently access
+the functions in this layer, thereby ensuring that both perl and
+extensions use the same runtime functions.
+
+If you have had prior exposure to Perl on Unix platforms, you will notice
+this port exhibits behavior different from what is documented. Most of the
+differences fall under one of these categories. We do not consider
+any of them to be serious limitations (especially when compared to the
+limited nature of some of the Win32 OSes themselves :)
=over 8
C<stat()> and C<lstat()> functions may not behave as documented. They
may return values that bear no resemblance to those reported on Unix
-platforms, and some fields may be completely bogus.
+platforms, and some fields (like the the one for inode) may be completely
+bogus.
=item *
-The following functions are currently unavailable: C<fork()>, C<exec()>,
-C<dump()>, C<kill()>, C<chown()>, C<link()>, C<symlink()>, C<chroot()>,
-C<setpgrp()>, C<getpgrp()>, C<setpriority()>, C<getpriority()>,
-C<syscall()>, C<fcntl()>, C<flock()>. This list is possibly incomplete.
+The following functions are currently unavailable: C<fork()>,
+C<dump()>, C<chown()>, C<link()>, C<symlink()>, C<chroot()>,
+C<setpgrp()> and related security functions, C<setpriority()>,
+C<getpriority()>, C<syscall()>, C<fcntl()>, C<getpw*()>,
+C<msg*()>, C<shm*()>, C<sem*()>, C<alarm()>, C<socketpair()>,
+C<*netent()>, C<*protoent()>, C<*servent()>, C<*hostent()>,
+C<getnetby*()>.
+This list is possibly incomplete.
=item *
=item *
-The behavior of C<system()> or the C<qx[]> operator (a.k.a. "backticks"),
-when used to call interactive commands, is ill-defined.
+The C<ioctl()> call is only supported on sockets (where it provides the
+functionality of ioctlsocket() in the Winsock API).
=item *
-C<$!> doesn't work reliably yet.
+Failure to spawn() a subprocess is indicated by setting $? to "255 << 8".
+C<$?> is set in a way compatible with Unix (i.e. the exitstatus of the
+subprocess is obtained by "$? >> 8", as described in the documentation).
=item *
-Building modules available on CPAN is mostly supported, but this
-hasn't been tested much yet. Expect strange problems, and be
-prepared to deal with the consequences.
+You can expect problems building modules available on CPAN if you
+build perl itself with -DUSE_THREADS. These problems should be resolved
+as we get closer to 5.005.
=item *
=item *
-Signal handling may not behave as on Unix platforms.
+Signal handling may not behave as on Unix platforms (where it
+doesn't exactly "behave", either :). For instance, calling C<die()>
+or C<exit()> from signal handlers will cause an exception, since most
+implementations of C<signal()> on Win32 are severely crippled.
+Thus, signals may work only for simple things like setting a flag
+variable in the handler. Using signals under this port should
+currently be considered unsupported.
=item *
-File globbing may not behave as on Unix platforms.
+C<kill()> is implemented, but doesn't have the semantics of
+C<raise()>, i.e. it doesn't send a signal to the identified process
+like it does on Unix platforms. Instead it immediately calls
+C<TerminateProcess(process,signal)>. Thus the signal argument is
+used to set the exit-status of the terminated process. In particular,
+C<kill(0,$pid)> will kill the process identified by C<$pid> (unlike
+on Unix). This behavior may change in future.
=item *
-Not all of the utilities that come with the Perl distribution
-are supported yet.
+File globbing may not behave as on Unix platforms. In particular,
+if you don't use perlglob.bat for globbing, it will understand
+wildcards only in the filename component (and not in the pathname).
+In other words, something like "print <*/*.pl>" will not print all the
+perl scripts in all the subdirectories one level under the current one
+(like it does on UNIX platforms). perlglob.exe is also dependent on
+the particular implementation of wildcard expansion in the vendor
+libraries used to build it (which varies wildly at the present time).
+Using perlglob.bat (or File::DosGlob) avoids these limitations, but
+still only provides DOS semantics (read "warts") for globbing.
=back
=over 4
-=item Gary Ng <F<71564.1743@CompuServe.COM>>
+Gary Ng E<lt>71564.1743@CompuServe.COME<gt>
-=item Gurusamy Sarathy <F<gsar@umich.edu>>
+Gurusamy Sarathy E<lt>gsar@umich.eduE<gt>
-=item Nick Ing-Simmons <F<nick@ni-s.u-net.com>>
+Nick Ing-Simmons E<lt>nick@ni-s.u-net.comE<gt>
=back
+This document is maintained by Gurusamy Sarathy.
+
=head1 SEE ALSO
L<perl>
Nick Ing-Simmons and Gurusamy Sarathy have made numerous and
sundry hacks since then.
-Last updated: 19 March 1997
+Borland support was added in 5.004_01 (Gurusamy Sarathy).
+
+GCC/mingw32 support was added in 5.005 (Nick Ing-Simmons).
+
+Support for PERL_OBJECT was added in 5.005 (ActiveState Tool Corp).
+
+Last updated: 18 January 1999
=cut