Provided by: perl-doc_5.30.0-9ubuntu0.5_all bug

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:

           <http://search.cpan.org/dist/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.)

           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  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

           (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".)

           Several required files will still be missing:

           •   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

           •   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}.

           •   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
       •   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.

       •   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.

       •   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 perlbug utility.

       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 run "perlbug" to create a bug report (you may have to send it manually
       if "perlbug" cannot find a mailer on your system).

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  <perlbug@perl.org>,
       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: 30 April 2019

perl v5.30.0                                       2023-11-23                                       PERLWIN32(1)