perlwin32(1)

PERLWIN32(1) Perl Programmers Reference Guide PERLWIN32(1)

NAME
perlwin32 - Perl under Windows

SYNOPSIS
These are instructions for building Perl under Windows 2000 and later.

DESCRIPTION
Before you start, you should glance through the README file found in
the top-level directory to which the Perl distribution was extracted.
Make sure you read and understand the terms under which this software
is being distributed.

Also make sure you read "BUGS AND CAVEATS" below for the known
limitations of this port.

The INSTALL file in the perl top-level has much information that is
only relevant to people building Perl on Unix-like systems. In
particular, you can safely ignore any information that talks about
"Configure".

You may also want to look at one other option for building a perl that
will work on Windows: the README.cygwin file, which give a different
set of rules to build a perl for Windows. This method 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 that file.

This set of instructions is meant to describe a so-called "native" port
of Perl to the Windows platform. This includes both 32-bit and 64-bit
Windows operating systems. The resulting Perl requires no additional
software to run (other than what came with your operating system).
Currently, this port is capable of using one of the following compilers
on the Intel x86 architecture:

Microsoft Visual C++ version 6.0 or later
Intel C++ Compiler (experimental)
Gcc by mingw.org gcc version 3.4.5 or later
with runtime < 3.21
Gcc by mingw-w64.org gcc version 4.4.3 or later

Note that the last two of these are actually competing projects both
delivering complete gcc toolchain for MS Windows:

<http://mingw.org>
Delivers gcc toolchain targeting 32-bit Windows platform.

<http://mingw-w64.org>
Delivers gcc toolchain targeting both 64-bit Windows and 32-bit
Windows platforms (despite the project name "mingw-w64" they are
not only 64-bit oriented). They deliver the native gcc compilers
and cross-compilers that are also supported by perl's makefile.

The Microsoft Visual C++ compilers are also now being given away free.
They are available as "Visual C++ Toolkit 2003" or "Visual C++
2005-2019 Express [or Community, from 2017] Edition" (and also as part
of the ".NET Framework SDK") and are the same compilers that ship with
"Visual C++ .NET 2003 Professional" or "Visual C++ 2005-2019
Professional" respectively.

This port can also be built on IA64/AMD64 using:

Microsoft Platform SDK Nov 2001 (64-bit compiler and tools)
MinGW64 compiler (gcc version 4.4.3 or later)

The Windows SDK can be downloaded from <http://www.microsoft.com/>.
The MinGW64 compiler is available at <http://mingw-w64.org>. The
latter is actually a cross-compiler targeting Win64. There's also a
trimmed down compiler (no java, or gfortran) suitable for building perl
available at: <http://strawberryperl.com/package/kmx/64_gcctoolchain/>

NOTE: If you're using a 32-bit compiler to build perl on a 64-bit
Windows operating system, then you should set the WIN64 environment
variable to "undef". Also, the trimmed down compiler only passes tests
when USE_ITHREADS *= define (as opposed to undef) and when the CFG *=
Debug line is commented out.

This port fully 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 "Usage Hints for
Perl on Windows" below for general hints about this.

Setting Up Perl on Windows
Make
You need a "make" program to build the sources. If you are using
Visual C++ or the Windows SDK tools, you can use nmake supplied
with Visual C++ or Windows SDK. You may also use, for Visual C++ or
Windows SDK, dmake or gmake instead of nmake. dmake is open source
software, but is not included with Visual C++ or Windows SDK.
Builds using gcc need dmake or gmake. nmake is not supported for
gcc builds. Parallel building is only supported with dmake and
gmake, not nmake. When using dmake it is recommended to use dmake
4.13 or newer for parallel building. Older dmakes, in parallel
mode, have very high CPU usage and pound the disk/filing system
with duplicate I/O calls in an aggressive polling loop.

A port of dmake for Windows is available from:

<https://metacpan.org/release/dmake>

Fetch and install dmake somewhere on your path.

Command Shell
Use the default "cmd" shell that comes with Windows. 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.

Make sure the path to the build directory does not contain spaces.
The build usually works in this circumstance, but some tests will
fail.

Microsoft Visual C++
The nmake that comes with Visual C++ will suffice for building.
Visual C requires that certain things be set up in the console
before Visual C will sucessfully run. To make a console box be able
to run the C compiler, you will need to beforehand, run the
"vcvars32.bat" file to compile for x86-32 and for x86-64
"vcvarsall.bat x64" or "vcvarsamd64.bat". On a typical install of a
Microsoft C compiler product, these batch files will already be in
your "PATH" environment variable so you may just type them without
an absolute path into your console. If you need to find the
absolute path to the batch file, it is usually found somewhere like
C:\Program Files\Microsoft Visual Studio\VC98\Bin. With some newer
Micrsoft C products (released after ~2004), the installer will put
a shortcut in the start menu to launch a new console window with
the console already set up for your target architecture (x86-32 or
x86-64 or IA64). With the newer compilers, you may also use the
older batch files if you choose so.

Microsoft Visual C++ 2008-2019 Express/Community Edition
These free versions of Visual C++ 2008-2019 Professional contain
the same compilers and linkers that ship with the full versions,
and also contain everything necessary to build Perl, rather than
requiring a separate download of the Windows SDK like previous
versions did.

These packages can be downloaded by searching in the Download
Center at
<http://www.microsoft.com/downloads/search.aspx?displaylang=en>.
(Providing exact links to these packages has proven a pointless
task because the links keep on changing so often.)

Install Visual C++ 2008-2019 Express/Community, then setup your
environment using, e.g.

C:\Program Files\Microsoft Visual Studio 12.0\Common7\Tools\vsvars32.bat

(assuming the default installation location was chosen).

Perl should now build using the win32/Makefile. You will need to
edit that file to set CCTYPE to one of MSVC90-MSVC142 first.

Microsoft Visual C++ 2005 Express Edition
This free version of Visual C++ 2005 Professional contains the same
compiler and linker that ship with the full version, but doesn't
contain everything necessary to build Perl.

You will also need to download the "Windows SDK" (the "Core SDK"
and "MDAC SDK" components are required) for more header files and
libraries.

These packages can both be downloaded by searching in the Download
Center at
<http://www.microsoft.com/downloads/search.aspx?displaylang=en>.
(Providing exact links to these packages has proven a pointless
task because the links keep on changing so often.)

Try to obtain the latest version of the Windows SDK. Sometimes
these packages contain a particular Windows OS version in their
name, but actually work on other OS versions too. For example, the
"Windows Server 2003 R2 Platform SDK" also runs on Windows XP SP2
and Windows 2000.

Install Visual C++ 2005 first, then the Platform SDK. Setup your
environment as follows (assuming default installation locations
were chosen):

SET PlatformSDKDir=C:\Program Files\Microsoft Platform SDK

SET PATH=%SystemRoot%\system32;%SystemRoot%;C:\Program Files\Microsoft Visual Studio 8\Common7\IDE;C:\Program Files\Microsoft Visual Studio 8\VC\BIN;C:\Program Files\Microsoft Visual Studio 8\Common7\Tools;C:\Program Files\Microsoft Visual Studio 8\SDK\v2.0\bin;C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727;C:\Program Files\Microsoft Visual Studio 8\VC\VCPackages;%PlatformSDKDir%\Bin

SET INCLUDE=C:\Program Files\Microsoft Visual Studio 8\VC\INCLUDE;%PlatformSDKDir%\include

SET LIB=C:\Program Files\Microsoft Visual Studio 8\VC\LIB;C:\Program Files\Microsoft Visual Studio 8\SDK\v2.0\lib;%PlatformSDKDir%\lib

SET LIBPATH=C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727

(The PlatformSDKDir might need to be set differently depending on
which version you are using. Earlier versions installed into
"C:\Program Files\Microsoft SDK", while the latest versions install
into version-specific locations such as "C:\Program Files\Microsoft
Platform SDK for Windows Server 2003 R2".)

Perl should now build using the win32/Makefile. You will need to
edit that file to set

CCTYPE = MSVC80

and to set CCHOME, CCINCDIR and CCLIBDIR as per the environment
setup above.

Microsoft Visual C++ Toolkit 2003
This free toolkit contains the same compiler and linker that ship
with Visual C++ .NET 2003 Professional, but doesn't contain
everything necessary to build Perl.

You will also need to download the "Platform SDK" (the "Core SDK"
and "MDAC SDK" components are required) for header files, libraries
and rc.exe, and ".NET Framework SDK" for more libraries and
nmake.exe. Note that the latter (which also includes the free
compiler and linker) requires the ".NET Framework Redistributable"
to be installed first. This can be downloaded and installed
separately, but is included in the "Visual C++ Toolkit 2003"
anyway.

These packages can all be downloaded by searching in the Download
Center at
<http://www.microsoft.com/downloads/search.aspx?displaylang=en>.
(Providing exact links to these packages has proven a pointless
task because the links keep on changing so often.)

Install the Toolkit first, then the Platform SDK, then the .NET
Framework SDK. Setup your environment as follows (assuming default
installation locations were chosen):

SET PlatformSDKDir=C:\Program Files\Microsoft Platform SDK

SET PATH=%SystemRoot%\system32;%SystemRoot%;C:\Program Files\Microsoft Visual C++ Toolkit 2003\bin;%PlatformSDKDir%\Bin;C:\Program Files\Microsoft.NET\SDK\v1.1\Bin

SET INCLUDE=C:\Program Files\Microsoft Visual C++ Toolkit 2003\include;%PlatformSDKDir%\include;C:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include

SET LIB=C:\Program Files\Microsoft Visual C++ Toolkit 2003\lib;%PlatformSDKDir%\lib;C:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\lib

Several required files will still be missing:

o cvtres.exe is required by link.exe when using a .res file. It
is actually installed by the .NET Framework SDK, but into a
location such as the following:

C:\WINDOWS\Microsoft.NET\Framework\v1.1.4322

Copy it from there to %PlatformSDKDir%\Bin

o lib.exe is normally used to build libraries, but link.exe with
the /lib option also works, so change win32/config.vc to use it
instead:

Change the line reading:

ar='lib'

to:

ar='link /lib'

It may also be useful to create a batch file called lib.bat in
C:\Program Files\Microsoft Visual C++ Toolkit 2003\bin
containing:

@echo off
link /lib %*

for the benefit of any naughty C extension modules that you
might want to build later which explicitly reference "lib"
rather than taking their value from $Config{ar}.

o setargv.obj is required to build perlglob.exe (and perl.exe if
the USE_SETARGV option is enabled). The Platform SDK supplies
this object file in source form in %PlatformSDKDir%\src\crt.
Copy setargv.c, cruntime.h and internal.h from there to some
temporary location and build setargv.obj using

cl.exe /c /I. /D_CRTBLD setargv.c

Then copy setargv.obj to %PlatformSDKDir%\lib

Alternatively, if you don't need perlglob.exe and don't need to
enable the USE_SETARGV option then you can safely just remove
all mention of $(GLOBEXE) from win32/Makefile and setargv.obj
won't be required anyway.

Perl should now build using the win32/Makefile. You will need to
edit that file to set

CCTYPE = MSVC70FREE

and to set CCHOME, CCINCDIR and CCLIBDIR as per the environment
setup above.

Microsoft Platform SDK 64-bit Compiler
The nmake that comes with the Platform SDK will suffice for
building Perl. Make sure you are building within one of the "Build
Environment" shells available after you install the Platform SDK
from the Start Menu.

GCC Perl can be compiled with gcc from MinGW (version 3.4.5 or later)
or from MinGW64 (version 4.4.3 or later). It can be downloaded
here:

<http://www.mingw.org/> <http://www.mingw-w64.org/>

You also need dmake or gmake. See "Make" above on how to get it.

Note that the MinGW build currently requires a MinGW runtime
version earlier than 3.21 (check __MINGW32_MAJOR_VERSION and
__MINGW32_MINOR_VERSION).

Note also that the C++ mode build currently fails with MinGW 3.4.5
and 4.7.2 or later, and with MinGW64 64-bit 6.3.0 or later.

Intel C++ Compiler
Experimental support for using Intel C++ Compiler has been added.
Edit win32/Makefile and pick the correct CCTYPE for the Visual C
that Intel C was installed into. Also uncomment __ICC to enable
Intel C on Visual C support. To set up the build environment, from
the Start Menu run IA-32 Visual Studio 20__ mode or Intel 64 Visual
Studio 20__ mode as appropriate. Then run nmake as usually in that
prompt box.

Only Intel C++ Compiler v12.1 has been tested. Other versions
probably will work. Using Intel C++ Compiler instead of Visual C
has the benefit of C99 compatibility which is needed by some CPAN
XS modules, while maintaining compatibility with Visual C object
code and Visual C debugging infrastructure unlike GCC.

Building
o 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++ or the Windows SDK, and
a GNU make "GNUmakefile" or dmake "makefile.mk" that will work for
all supported compilers. The defaults in the gmake and dmake
makefile are setup to build using MinGW/gcc.

o Edit the GNUmakefile, makefile.mk (or Makefile, if you're using
nmake) and change the values of INST_DRV and INST_TOP. You can
also enable various build flags. These are explained in the
makefiles.

Note that it is generally not a good idea to try to build a perl
with INST_DRV and INST_TOP set to a path that already exists from a
previous build. In particular, this may cause problems with the
lib/ExtUtils/t/Embed.t test, which attempts to build a test program
and may end up building against the installed perl's lib/CORE
directory rather than the one being tested.

You will have to make sure that CCTYPE is set correctly and that
CCHOME points to wherever you installed your compiler. For GCC
this should be the directory that contains the bin, include and lib
directories.

If building with the cross-compiler provided by mingw-w64.org
you'll need to uncomment the line that sets GCCCROSS in the
makefile.mk. Do this only if it's the cross-compiler - ie only if
the bin folder doesn't contain a gcc.exe. (The cross-compiler does
not provide a gcc.exe, g++.exe, ar.exe, etc. Instead, all of these
executables are prefixed with 'x86_64-w64-mingw32-'.)

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.

You may also need to comment out the "DELAYLOAD = ..." line in the
Makefile if you're using VC++ 6.0 without the latest service pack
and the linker reports an internal error.

If you want build some core extensions statically into perl's dll,
specify them in the STATIC_EXT macro.

NOTE: The USE_64_BIT_INT build option is not supported with the
32-bit Visual C++ 6.0 compiler.

Be sure to read the instructions near the top of the makefiles
carefully.

o Type "dmake" ("gmake" for GNU make, or "nmake" if you are using
that make).

This should build everything. Specifically, it will create
perl.exe, perl530.dll 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.

To try dmake's parallel mode, type "dmake -P2", where 2, is the
maximum number of parallel jobs you want to run. A number of things
in the build process will run in parallel, but there are
serialization points where you will see just 1 CPU maxed out. This
is normal.

Similarly you can build in parallel with GNU make, type "gmake -j2"
to build with two parallel jobs, or higher for more.

If you are advanced enough with building C code, here is a
suggestion to speed up building perl, and the later "make test".
Try to keep your PATH environmental variable with the least number
of folders possible (remember to keep your C compiler's folders
there). "C:\WINDOWS\system32" or "C:\WINNT\system32" depending on
your OS version should be first folder in PATH, since "cmd.exe" is
the most commonly launched program during the build and later
testing.

Testing Perl on Windows
Type "dmake test" (or "gmake test", "nmake test"). This will run most
of the tests from the testsuite (many tests will be skipped).

There should be no test failures.

If you build with Visual C++ 2013 then three tests currently may fail
with Daylight Saving Time related problems: t/io/fs.t,
cpan/HTTP-Tiny/t/110_mirror.t and lib/File/Copy.t. The failures are
caused by bugs in the CRT in VC++ 2013 which are fixed in VC++2015 and
later, as explained by Microsoft here:
<https://connect.microsoft.com/VisualStudio/feedback/details/811534/utime-sometimes-fails-to-set-the-correct-file-times-in-visual-c-2013>.
In the meantime, if you need fixed "stat" and "utime" functions then
have a look at the CPAN distribution Win32::UTCFileTime.

If you build with Visual C++ 2015 or later then
ext/XS-APItest/t/locale.t may crash (after all its tests have passed).
This is due to a regression in the Universal CRT introduced in the
Windows 10 April 2018 Update, and will be fixed in the May 2019 Update,
as explained here:
<https://developercommunity.visualstudio.com/content/problem/519486/setlocalelc-numeric-iso-latin-16-fails-then-succee.html>.

If you build with certain versions (e.g. 4.8.1) of gcc from
www.mingw.org then ext/POSIX/t/time.t may fail test 17 due to a known
bug in those gcc builds: see
<http://sourceforge.net/p/mingw/bugs/2152/>.

Some test failures may occur if you use a command shell other than the
native "cmd.exe", or if you are building from a path that contains
spaces. So don't do that.

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.

Furthermore, you should make sure that during "make test" you do not
have any GNU tool packages in your path: some toolkits like Unixutils
include some tools ("type" for instance) which override the Windows
ones and makes tests fail. Remove them from your path while testing to
avoid these errors.

To see the output of specific failing tests run the harness from the t
directory:

# assuming you're starting from the win32 directory
cd ..\win32
.\perl harness <list of tests>

Please report any other failures as described under "BUGS AND CAVEATS".

Installation of Perl on Windows
Type "dmake install" (or "gmake install", "nmake install"). This will
put the newly built perl and the libraries under whatever "INST_TOP"
points to in the Makefile. It will also install the pod documentation
under "$INST_TOP\$INST_VER\lib\pod" and HTML versions of the same under
"$INST_TOP\$INST_VER\lib\pod\html".

To use the Perl you just installed you will need to add a new entry to
your PATH environment variable: "$INST_TOP\bin", e.g.

set PATH=c:\perl\bin;%PATH%

If you opted to uncomment "INST_VER" and "INST_ARCH" in the makefile
then the installation structure is a little more complicated and you
will need to add two new PATH components instead:
"$INST_TOP\$INST_VER\bin" and "$INST_TOP\$INST_VER\bin\$ARCHNAME", e.g.

set PATH=c:\perl\5.6.0\bin;c:\perl\5.6.0\bin\MSWin32-x86;%PATH%

Usage Hints for Perl on Windows
Environment Variables
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).

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 perlrun.

You can also control the shell that perl uses to run system() and
backtick commands via PERL5SHELL. See perlrun.

Perl does not depend on the registry, but it can look up certain
default values if you choose to put them there unless disabled at
build time with USE_NO_REGISTRY. On Perl process start Perl checks
if "HKEY_CURRENT_USER\Software\Perl" and
"HKEY_LOCAL_MACHINE\Software\Perl" exist. If the keys exists, they
will be checked for remainder of the Perl process's run life for
certain entries. Entries in "HKEY_CURRENT_USER\Software\Perl"
override entries in "HKEY_LOCAL_MACHINE\Software\Perl". One or
more of the following entries (of type REG_SZ or REG_EXPAND_SZ) may
be set in the keys:

lib-$] version-specific standard library path to add to @INC
lib standard library path to add to @INC
sitelib-$] version-specific site library path to add to @INC
sitelib site library path to add to @INC
vendorlib-$] version-specific vendor library path to add to @INC
vendorlib vendor library path to add to @INC
PERL* fallback for all %ENV lookups that begin with "PERL"

Note the $] in the above is not literal. Substitute whatever
version of perl you want to honor that entry, e.g. 5.6.0. Paths
must be separated with semicolons, as usual on Windows.

File Globbing
By default, perl handles file globbing using the File::Glob
extension, which provides portable globbing.

If you want perl to use globbing that emulates the quirks of DOS
filename conventions, you might want to consider using
File::DosGlob to override the internal glob() implementation. See
File::DosGlob for details.

Using perl from the command line
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 offers by way of a command shell.

The crucial thing to understand about the Windows environment is
that the command line you type in is processed twice before Perl
sees it. First, your command shell (usually CMD.EXE) preprocesses
the command line, to handle redirection, environment variable
expansion, and location of the executable to run. Then, the perl
executable splits the remaining command line into individual
arguments, using the C runtime library upon which Perl was built.

It is particularly important to note that neither the shell nor the
C runtime do any wildcard expansions of command-line arguments (so
wildcards need not be quoted). Also, the quoting behaviours of the
shell and the C runtime are rudimentary at best (and may, if you
are using a non-standard shell, be inconsistent). The only
(useful) quote character is the double quote ("). It can be used
to protect spaces and other special characters in arguments.

The Windows documentation describes the shell parsing rules here:
<http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/cmd.mspx?mfr=true>
and the C runtime parsing rules here:
<http://msdn.microsoft.com/en-us/library/17w5ykft%28v=VS.100%29.aspx>.

Here are some further observations based on experiments: The C
runtime breaks arguments at spaces and passes them to programs in
argc/argv. Double quotes 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 C
runtime.

The file redirection characters "<", ">", and "|" can be quoted by
double quotes (although there are suggestions that this may not
always be true). Single quotes are not treated as quotes by the
shell or the C runtime, they 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, but this
appears to be a shell feature, and the caret is not stripped from
the command line, so Perl still sees it (and the C runtime phase
does not treat the caret as a quote character).

Here are some examples of usage of the "cmd" shell:

This prints two doublequotes:

perl -e "print '\"\"' "

This does the same:

perl -e "print \"\\\"\\\"\" "

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 Windows 9x
is left as an exercise to the reader :)

One particularly pernicious problem with the 4NT command shell for
Windows is that it (nearly) always treats a % character as
indicating that environment variable expansion is needed. Under
this shell, it is therefore important to always double any %
characters which you want Perl to see (for example, for hash
variables), even when they are quoted.

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.cpan.org/> for more information on CPAN.

Note that not all of the extensions available from CPAN may work in
the Windows environment; you should check the information at
<http://www.cpantesters.org/> before investing too much effort into
porting modules that don't readily build.

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:

<http://download.microsoft.com/download/vc15/Patch/1.52/W95/EN-US/nmake15.exe>

Another option is to use the make written in Perl, available from
CPAN.

<http://www.cpan.org/modules/by-module/Make/>

You may also use dmake or gmake. See "Make" above on how to get
it.

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 before running "perl
Makefile.PL" or any invocation of make.

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 GitHub issue tracker
at <https://github.com/Perl/perl5/issues>.

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.

Instead, the following solution works rather well. The nice things
about it are 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; and
4) you can extend the method to add any customizations (or even
entirely different kinds of wildcard expansion).

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.

Notes on 64-bit Windows
Windows .NET Server supports the LLP64 data model on the Intel
Itanium architecture.

The LLP64 data model is different from the LP64 data model that is
the norm on 64-bit Unix platforms. In the former, "int" and "long"
are both 32-bit data types, while pointers are 64 bits wide. In
addition, there is a separate 64-bit wide integral type, "__int64".
In contrast, the LP64 data model that is pervasive on Unix
platforms provides "int" as the 32-bit type, while both the "long"
type and pointers are of 64-bit precision. Note that both models
provide for 64-bits of addressability.

64-bit Windows running on Itanium is capable of running 32-bit x86
binaries transparently. This means that you could use a 32-bit
build of Perl on a 64-bit system. Given this, why would one want
to build a 64-bit build of Perl? Here are some reasons why you
would bother:

o A 64-bit native application will run much more efficiently on
Itanium hardware.

o There is no 2GB limit on process size.

o Perl automatically provides large file support when built under
64-bit Windows.

o Embedding Perl inside a 64-bit application.

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. Windows has no
comparable means to indicate arbitrary files are executables.

Instead, all available methods to execute plain text files on Windows
rely on the file "extension". There are three methods to use this to
execute perl scripts:

1. There is a facility called "file extension associations". This
can be manipulated via the two commands "assoc" and "ftype"
that come standard with Windows. Type "ftype /?" for a
complete example of how to set this up for perl scripts (Say
what? You thought Windows wasn't perl-ready? :).

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.

3. Using "pl2bat" has a few problems: the file name gets changed,
so scripts that rely on $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 Windows 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

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.

"perldoc" is also a useful tool for browsing information contained in
the documentation, especially in conjunction with a pager like "less"
(recent versions of which have Windows 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".

One common mistake when using this port with a GUI library like "Tk" is
assuming that Perl's normal behavior of opening a command-line window
will go away. This isn't the case. If you want to start a copy of
"perl" without opening a command-line window, use the "wperl"
executable built during the installation process. Usage is exactly the
same as normal "perl" on Windows, except that options like "-h" don't
work (since they need a command-line window to print to).

If you find bugs in perl, you can report them to
<https://github.com/Perl/perl5/issues>.

BUGS AND CAVEATS
Norton AntiVirus interferes with the build process, particularly if set
to "AutoProtect, All Files, when Opened". Unlike large applications the
perl build process opens and modifies a lot of files. Having the the
AntiVirus scan each and every one slows build the process
significantly. Worse, with PERLIO=stdio the build process fails with
peculiar messages as the virus checker interacts badly with
miniperl.exe writing configure files (it seems to either catch file
part written and treat it as suspicious, or virus checker may have it
"locked" in a way which inhibits miniperl updating it). The build does
complete with

set PERLIO=perlio

but that may be just luck. Other AntiVirus software may have similar
issues.

A git GUI shell extension for Windows such as TortoiseGit will cause
the build and later "make test" to run much slower since every file is
checked for its git status as soon as it is created and/or modified.
TortoiseGit doesn't cause any test failures or build problems unlike
the antivirus software described above, but it does cause similar
slowness. It is suggested to use Task Manager to look for background
processes which use high CPU amounts during the building process.

Some of the built-in functions do not act exactly as documented in
perlfunc, and a few are not implemented at all. To avoid surprises,
particularly if you have had prior exposure to Perl in other operating
environments or if you intend to write code that will be portable to
other environments, see perlport for a reasonably definitive list of
these differences.

Not all extensions available from CPAN may build or work properly in
the Windows environment. See "Building Extensions".

Most "socket()" related calls are supported, but they may not behave as
on Unix platforms. See perlport for the full list.

Signal handling may not behave as on Unix platforms (where it doesn't
exactly "behave", either :). For instance, calling "die()" or "exit()"
from signal handlers will cause an exception, since most
implementations of "signal()" on Windows 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.

Please send detailed descriptions of any problems and solutions that
you may find to <<https://github.com/Perl/perl5/issues>>, along with
the output produced by "perl -V".

ACKNOWLEDGEMENTS
The use of a camel with the topic of Perl is a trademark of O'Reilly
and Associates, Inc. Used with permission.

AUTHORS
Gary Ng <71564.1743@CompuServe.COM>
Gurusamy Sarathy <gsar@activestate.com>
Nick Ing-Simmons <nick@ing-simmons.net>
Jan Dubois <jand@activestate.com>
Steve Hay <steve.m.hay@googlemail.com>

This document is maintained by Jan Dubois.