Provided by: perl-doc_5.38.2-3.2ubuntu0.1_all 
NAME
perlwin32 - Perl under Windows
SYNOPSIS
These are instructions for building Perl under Windows 7 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 and x86_64 architectures:
Microsoft Visual C++ version 12.0 or later
Intel C++ Compiler (experimental)
Gcc by mingw.org gcc version 3.4.5-5.3.0
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:
<https://osdn.net/projects/mingw/>
Delivers gcc toolchain building 32-bit executables (which can be used both 32 and 64 bit Windows
platforms)
<https://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++
2013-2022 Community Edition" and are the same compilers that ship with "Visual C++ 2013-2022
Professional".
Visual C++ 2013 is capable of targeting XP and Windows Server 2003 but the build host requirement is
Windows 7/Windows Server 2012. For more details see
https://docs.microsoft.com/en-us/visualstudio/productinfo/vs2013-compatibility-vs and
https://docs.microsoft.com/en-us/visualstudio/productinfo/vs2013-sysrequirements-vs
The MinGW64 compiler is available at <https://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: <https://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++, you can use nmake
supplied with Visual C++. You may also use gmake instead of nmake. Builds using gcc need gmake.
nmake is not supported for gcc builds. Parallel building is only supported with gmake, not nmake.
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 successfully run. To make a console box be
able to run the C compiler, you will need to beforehand, run "vcvarsall.bat x86" to compile for
x86-32 and for x86-64 "vcvarsall.bat amd64". 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 (x86)\Microsoft Visual Studio 14.0\VC.
With some newer Microsoft 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++ 2013-2022 Community Edition
These free versions of Visual C++ 2013-2022 Professional contain the same compilers and linkers that
ship with the full versions, and also contain everything necessary to build Perl.
These packages can be downloaded from <https://visualstudio.microsoft.com/>.
Install Visual C++ 2013-2022 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 "MSVC120"-"MSVC143" first.
Microsoft C++ Build Tools
There's also a standalone (IDE-less) version of the build tools mentioned above containing the MSVC
compiler available for download from <https://visualstudio.microsoft.com/visual-cpp-build-tools/>.
This is also referred to as Build Tools for Visual Studio.
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:
<https://osdn.net/projects/mingw/> <https://www.mingw-w64.org/>
You also need gmake. Usually it comes with MinGW but its executable may have a different name, such
as mingw32-make.exe.
Note that the MinGW build currently fails with version 6.3.0 or later.
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 usual 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
• 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 GNU make
GNUmakefile that will work for all supported compilers. The defaults in the "gmake" makefile are set
up to build with MinGW/gcc.
• Edit the GNUmakefile (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 GNUmakefile. 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.
If you want build some core extensions statically into "perl"'s DLL, specify them in the "STATIC_EXT"
macro.
Be sure to read the instructions near the top of the makefiles carefully.
• Type "gmake" (or "nmake" if you are using that version of "make").
This should build everything. Specifically, it will create perl.exe, perl538.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 "gmake"'s parallel mode, type "gmake -j2" 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.
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" environment 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 "gmake test" (or "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 mingw then ext/POSIX/t/time.t may fail test
17 due to a known bug in those gcc builds: see <https://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 "gmake
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 "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:
<https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/cmd> and the C
runtime parsing rules here: <https://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 <https://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 <https://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.
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
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:
• A 64-bit native application will run much more efficiently on Itanium hardware.
• There is no 2GB limit on process size.
• Perl automatically provides large file support when built under 64-bit Windows.
• 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
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 report detailed descriptions of any problems and solutions that you may find at
<<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.
SEE ALSO
perl
HISTORY
This port was originally contributed by Gary Ng around 5.003_24, and borrowed from the Hip Communications
port that was available at the time. Various people have made numerous and sundry hacks since then.
GCC/mingw32 support was added in 5.005 (Nick Ing-Simmons).
Support for PERL_OBJECT was added in 5.005 (ActiveState Tool Corp).
Support for fork() emulation was added in 5.6 (ActiveState Tool Corp).
Win9x support was added in 5.6 (Benjamin Stuhl).
Support for 64-bit Windows added in 5.8 (ActiveState Corp).
Last updated: 06 October 2021
perl v5.38.2 2025-04-08 PERLWIN32(1)