Ubuntu Manpage: ExtUtils::MakeMaker - Create a module Makefile

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NAME

       ExtUtils::MakeMaker - Create a module Makefile

SYNOPSIS

         use ExtUtils::MakeMaker;

         WriteMakefile(
             NAME              => "Foo::Bar",
             VERSION_FROM      => "lib/Foo/Bar.pm",
         );

DESCRIPTION

This utility is designed to write a Makefile for an extension module from a Makefile.PL. It is based on
the Makefile.SH model provided by Andy Dougherty and the perl5-porters.

It splits the task of generating the Makefile into several subroutines that can be individually
overridden. Each subroutine returns the text it wishes to have written to the Makefile.

As there are various Make programs with incompatible syntax, which use operating system shells, again
with incompatible syntax, it is important for users of this module to know which flavour of Make a
Makefile has been written for so they'll use the correct one and won't have to face the possibly
bewildering errors resulting from using the wrong one.

On POSIX systems, that program will likely be GNU Make; on Microsoft Windows, it will be either Microsoft
NMake, DMake or GNU Make. See the section on the "MAKE" parameter for details.

ExtUtils::MakeMaker (EUMM) is object oriented. Each directory below the current directory that contains a
Makefile.PL is treated as a separate object. This makes it possible to write an unlimited number of
Makefiles with a single invocation of WriteMakefile().

All inputs to WriteMakefile are Unicode characters, not just octets. EUMM seeks to handle all of these
correctly. It is currently still not possible to portably use Unicode characters in module names, because
this requires Perl to handle Unicode filenames, which is not yet the case on Windows.

See ExtUtils::MakeMaker::FAQ for details of the design and usage.

How To Write A Makefile.PL
See ExtUtils::MakeMaker::Tutorial.

The long answer is the rest of the manpage :-)

Default Makefile Behaviour
The generated Makefile enables the user of the extension to invoke

perl Makefile.PL # optionally "perl Makefile.PL verbose"
make
make test # optionally set TEST_VERBOSE=1
make install # See below

The Makefile to be produced may be altered by adding arguments of the form "KEY=VALUE". E.g.

perl Makefile.PL INSTALL_BASE=~

Other interesting targets in the generated Makefile are

make config # to check if the Makefile is up-to-date
make clean # delete local temp files (Makefile gets renamed)
make realclean # delete derived files (including ./blib)
make ci # check in all the files in the MANIFEST file
make dist # see below the Distribution Support section

make test
MakeMaker checks for the existence of a file named test.pl in the current directory, and if it exists it
executes the script with the proper set of perl "-I" options.

MakeMaker also checks for any files matching glob("t/*.t"). It will execute all matching files in
alphabetical order via the Test::Harness module with the "-I" switches set correctly.

You can also organize your tests within subdirectories in the t/ directory. To do so, use the test
directive in your Makefile.PL. For example, if you had tests in:

t/foo
t/foo/bar

You could tell make to run tests in both of those directories with the following directives:

test => {TESTS => 't/*/*.t t/*/*/*.t'}
test => {TESTS => 't/foo/*.t t/foo/bar/*.t'}

The first will run all test files in all first-level subdirectories and all subdirectories they contain.
The second will run tests in only the t/foo and t/foo/bar.

If you'd like to see the raw output of your tests, set the "TEST_VERBOSE" variable to true.

make test TEST_VERBOSE=1

If you want to run particular test files, set the "TEST_FILES" variable. It is possible to use globbing
with this mechanism.

make test TEST_FILES='t/foobar.t t/dagobah*.t'

Windows users who are using "nmake" should note that due to a bug in "nmake", when specifying
"TEST_FILES" you must use back-slashes instead of forward-slashes.

nmake test TEST_FILES='t\foobar.t t\dagobah*.t'

make testdb
A useful variation of the above is the target "testdb". It runs the test under the Perl debugger (see
perldebug). If the file test.pl exists in the current directory, it is used for the test.

If you want to debug some other testfile, set the "TEST_FILE" variable thusly:

make testdb TEST_FILE=t/mytest.t

By default the debugger is called using "-d" option to perl. If you want to specify some other option,
set the "TESTDB_SW" variable:

make testdb TESTDB_SW=-Dx

make install
make alone puts all relevant files into directories that are named by the macros INST_LIB, INST_ARCHLIB,
INST_SCRIPT, INST_MAN1DIR and INST_MAN3DIR. All these default to something below ./blib if you are not
building below the perl source directory. If you are building below the perl source, INST_LIB and
INST_ARCHLIB default to ../../lib, and INST_SCRIPT is not defined.

The install target of the generated Makefile copies the files found below each of the INST_* directories
to their INSTALL* counterparts. Which counterparts are chosen depends on the setting of INSTALLDIRS
according to the following table:

INSTALLDIRS set to
perl site vendor

PERLPREFIX SITEPREFIX VENDORPREFIX
INST_ARCHLIB INSTALLARCHLIB INSTALLSITEARCH INSTALLVENDORARCH
INST_LIB INSTALLPRIVLIB INSTALLSITELIB INSTALLVENDORLIB
INST_BIN INSTALLBIN INSTALLSITEBIN INSTALLVENDORBIN
INST_SCRIPT INSTALLSCRIPT INSTALLSITESCRIPT INSTALLVENDORSCRIPT
INST_MAN1DIR INSTALLMAN1DIR INSTALLSITEMAN1DIR INSTALLVENDORMAN1DIR
INST_MAN3DIR INSTALLMAN3DIR INSTALLSITEMAN3DIR INSTALLVENDORMAN3DIR

The INSTALL... macros in turn default to their %Config ($Config{installprivlib}, $Config{installarchlib},
etc.) counterparts.

You can check the values of these variables on your system with

perl '-V:install.*'

And to check the sequence in which the library directories are searched by perl, run

perl -le 'print join $/, @INC'

Sometimes older versions of the module you're installing live in other directories in @INC. Because Perl
loads the first version of a module it finds, not the newest, you might accidentally get one of these
older versions even after installing a brand new version. To delete all other versions of the module
you're installing (not simply older ones) set the "UNINST" variable.

make install UNINST=1

INSTALL_BASE
INSTALL_BASE can be passed into Makefile.PL to change where your module will be installed. INSTALL_BASE
is more like what everyone else calls "prefix" than PREFIX is.

To have everything installed in your home directory, do the following.

# Unix users, INSTALL_BASE=~ works fine
perl Makefile.PL INSTALL_BASE=/path/to/your/home/dir

Like PREFIX, it sets several INSTALL* attributes at once. Unlike PREFIX it is easy to predict where the
module will end up. The installation pattern looks like this:

INSTALLARCHLIB INSTALL_BASE/lib/perl5/$Config{archname}
INSTALLPRIVLIB INSTALL_BASE/lib/perl5
INSTALLBIN INSTALL_BASE/bin
INSTALLSCRIPT INSTALL_BASE/bin
INSTALLMAN1DIR INSTALL_BASE/man/man1
INSTALLMAN3DIR INSTALL_BASE/man/man3

INSTALL_BASE in MakeMaker and "--install_base" in Module::Build (as of 0.28) install to the same
location. If you want MakeMaker and Module::Build to install to the same location simply set
INSTALL_BASE and "--install_base" to the same location.

INSTALL_BASE was added in 6.31.

PREFIX and LIB attribute
PREFIX and LIB can be used to set several INSTALL* attributes in one go. Here's an example for
installing into your home directory.

# Unix users, PREFIX=~ works fine
perl Makefile.PL PREFIX=/path/to/your/home/dir

This will install all files in the module under your home directory, with man pages and libraries going
into an appropriate place (usually ~/man and ~/lib). How the exact location is determined is complicated
and depends on how your Perl was configured. INSTALL_BASE works more like what other build systems call
"prefix" than PREFIX and we recommend you use that instead.

Another way to specify many INSTALL directories with a single parameter is LIB.

perl Makefile.PL LIB=~/lib

This will install the module's architecture-independent files into ~/lib, the architecture-dependent
files into ~/lib/$archname.

Note, that in both cases the tilde expansion is done by MakeMaker, not by perl by default, nor by make.

Conflicts between parameters LIB, PREFIX and the various INSTALL* arguments are resolved so that:

• setting LIB overrides any setting of INSTALLPRIVLIB, INSTALLARCHLIB, INSTALLSITELIB, INSTALLSITEARCH
(and they are not affected by PREFIX);

• without LIB, setting PREFIX replaces the initial $Config{prefix} part of those INSTALL* arguments,
even if the latter are explicitly set (but are set to still start with $Config{prefix}).

If the user has superuser privileges, and is not working on AFS or relatives, then the defaults for
INSTALLPRIVLIB, INSTALLARCHLIB, INSTALLSCRIPT, etc. will be appropriate, and this incantation will be the
best:

perl Makefile.PL;
make;
make test
make install

make install by default writes some documentation of what has been done into the file
"$(INSTALLARCHLIB)/perllocal.pod". This feature can be bypassed by calling make pure_install.

AFS users
will have to specify the installation directories as these most probably have changed since perl itself
has been installed. They will have to do this by calling

perl Makefile.PL INSTALLSITELIB=/afs/here/today \
INSTALLSCRIPT=/afs/there/now INSTALLMAN3DIR=/afs/for/manpages
make

Be careful to repeat this procedure every time you recompile an extension, unless you are sure the AFS
installation directories are still valid.

Static Linking of a new Perl Binary
An extension that is built with the above steps is ready to use on systems supporting dynamic loading. On
systems that do not support dynamic loading, any newly created extension has to be linked together with
the available resources. MakeMaker supports the linking process by creating appropriate targets in the
Makefile whenever an extension is built. You can invoke the corresponding section of the makefile with

make perl

That produces a new perl binary in the current directory with all extensions linked in that can be found
in INST_ARCHLIB, SITELIBEXP, and PERL_ARCHLIB. To do that, MakeMaker writes a new Makefile, on UNIX, this
is called Makefile.aperl (may be system dependent). If you want to force the creation of a new perl, it
is recommended that you delete this Makefile.aperl, so the directories are searched through for linkable
libraries again.

The binary can be installed into the directory where perl normally resides on your machine with

make inst_perl

To produce a perl binary with a different name than "perl", either say

perl Makefile.PL MAP_TARGET=myperl
make myperl
make inst_perl

or say

perl Makefile.PL
make myperl MAP_TARGET=myperl
make inst_perl MAP_TARGET=myperl

In any case you will be prompted with the correct invocation of the "inst_perl" target that installs the
new binary into INSTALLBIN.

make inst_perl by default writes some documentation of what has been done into the file
"$(INSTALLARCHLIB)/perllocal.pod". This can be bypassed by calling make pure_inst_perl.

Warning: the inst_perl: target will most probably overwrite your existing perl binary. Use with care!

Sometimes you might want to build a statically linked perl although your system supports dynamic loading.
In this case you may explicitly set the linktype with the invocation of the Makefile.PL or make:

perl Makefile.PL LINKTYPE=static # recommended

make LINKTYPE=static # works on most systems

Determination of Perl Library and Installation Locations
MakeMaker needs to know, or to guess, where certain things are located. Especially INST_LIB and
INST_ARCHLIB (where to put the files during the make(1) run), PERL_LIB and PERL_ARCHLIB (where to read
existing modules from), and PERL_INC (header files and "libperl*.*").

Extensions may be built either using the contents of the perl source directory tree or from the installed
perl library. The recommended way is to build extensions after you have run 'make install' on perl
itself. You can do that in any directory on your hard disk that is not below the perl source tree. The
support for extensions below the ext directory of the perl distribution is only good for the standard
extensions that come with perl.

If an extension is being built below the "ext/" directory of the perl source then MakeMaker will set
PERL_SRC automatically (e.g., "../.."). If PERL_SRC is defined and the extension is recognized as a
standard extension, then other variables default to the following:

PERL_INC = PERL_SRC
PERL_LIB = PERL_SRC/lib
PERL_ARCHLIB = PERL_SRC/lib
INST_LIB = PERL_LIB
INST_ARCHLIB = PERL_ARCHLIB

If an extension is being built away from the perl source then MakeMaker will leave PERL_SRC undefined and
default to using the installed copy of the perl library. The other variables default to the following:

PERL_INC = $archlibexp/CORE
PERL_LIB = $privlibexp
PERL_ARCHLIB = $archlibexp
INST_LIB = ./blib/lib
INST_ARCHLIB = ./blib/arch

If perl has not yet been installed then PERL_SRC can be defined on the command line as shown in the
previous section.

Which architecture dependent directory?
If you don't want to keep the defaults for the INSTALL* macros, MakeMaker helps you to minimize the
typing needed: the usual relationship between INSTALLPRIVLIB and INSTALLARCHLIB is determined by
Configure at perl compilation time. MakeMaker supports the user who sets INSTALLPRIVLIB. If
INSTALLPRIVLIB is set, but INSTALLARCHLIB not, then MakeMaker defaults the latter to be the same
subdirectory of INSTALLPRIVLIB as Configure decided for the counterparts in %Config, otherwise it
defaults to INSTALLPRIVLIB. The same relationship holds for INSTALLSITELIB and INSTALLSITEARCH.

MakeMaker gives you much more freedom than needed to configure internal variables and get different
results. It is worth mentioning that make(1) also lets you configure most of the variables that are used
in the Makefile. But in the majority of situations this will not be necessary, and should only be done if
the author of a package recommends it (or you know what you're doing).

Using Attributes and Parameters
The following attributes may be specified as arguments to WriteMakefile() or as NAME=VALUE pairs on the
command line. Attributes that became available with later versions of MakeMaker are indicated.

In order to maintain portability of attributes with older versions of MakeMaker you may want to use
App::EUMM::Upgrade with your "Makefile.PL".

ABSTRACT
One line description of the module. Will be included in PPD file.

ABSTRACT_FROM
Name of the file that contains the package description. MakeMaker looks for a line in the POD matching
/^($package\s-\s)(.*)/. This is typically the first line in the "=head1 NAME" section. $2 becomes the
abstract.

AUTHOR
Array of strings containing name (and email address) of package author(s). Is used in CPAN Meta files
(META.yml or META.json) and PPD (Perl Package Description) files for PPM (Perl Package Manager).

BINARY_LOCATION
Used when creating PPD files for binary packages. It can be set to a full or relative path or URL to
the binary archive for a particular architecture. For example:

perl Makefile.PL BINARY_LOCATION=x86/Agent.tar.gz

builds a PPD package that references a binary of the "Agent" package, located in the "x86" directory
relative to the PPD itself.

BUILD_REQUIRES
Available in version 6.55_03 and above.

A hash of modules that are needed to build your module but not run it.

This will go into the "build_requires" field of your META.yml and the "build" of the "prereqs" field of
your META.json.

Defaults to "{ "ExtUtils::MakeMaker" => 0 }" if this attribute is not specified.

The format is the same as PREREQ_PM.

C Ref to array of *.c file names. Initialised from a directory scan and the values portion of the XS
attribute hash. This is not currently used by MakeMaker but may be handy in Makefile.PLs.

CCFLAGS
String that will be included in the compiler call command line between the arguments INC and OPTIMIZE.
Note that setting this will overwrite its default value ($Config::Config{ccflags}); to preserve that,
include the default value directly, e.g.:

CCFLAGS => "$Config::Config{ccflags} ..."

The default value is taken from $Config{ccflags}. When overriding CCFLAGS, make sure to include the
$Config{ccflags} settings to avoid binary incompatibilities.

CONFIG
Arrayref. E.g. [qw(archname manext)] defines ARCHNAME & MANEXT from config.sh. MakeMaker will add to
CONFIG the following values anyway: ar cc cccdlflags ccdlflags cpprun dlext dlsrc ld lddlflags ldflags
libc lib_ext obj_ext ranlib sitelibexp sitearchexp so

CONFIGURE
CODE reference. The subroutine should return a hash reference. The hash may contain further attributes,
e.g. {LIBS => ...}, that have to be determined by some evaluation method.

CONFIGURE_REQUIRES
Available in version 6.52 and above.

A hash of modules that are required to run Makefile.PL itself, but not to run your distribution.

This will go into the "configure_requires" field of your META.yml and the "configure" of the "prereqs"
field of your META.json.

Defaults to "{ "ExtUtils::MakeMaker" => 0 }" if this attribute is not specified.

The format is the same as PREREQ_PM.

DEFINE
Something like "-DHAVE_UNISTD_H"

DESTDIR
This is the root directory into which the code will be installed. It prepends itself to the normal
prefix. For example, if your code would normally go into /usr/local/lib/perl you could set
DESTDIR=~/tmp/ and installation would go into ~/tmp/usr/local/lib/perl.

This is primarily of use for people who repackage Perl modules.

NOTE: Due to the nature of make, it is important that you put the trailing slash on your DESTDIR.
~/tmp/ not ~/tmp.

DIR
Ref to array of subdirectories containing Makefile.PLs e.g. ['sdbm'] in ext/SDBM_File

DISTNAME
A safe filename for the package.

Defaults to NAME below but with :: replaced with -.

For example, Foo::Bar becomes Foo-Bar.

DISTVNAME
Your name for distributing the package with the version number included. This is used by 'make dist'
to name the resulting archive file.

Defaults to DISTNAME-VERSION.

For example, version 1.04 of Foo::Bar becomes Foo-Bar-1.04.

On some OS's where . has special meaning VERSION_SYM may be used in place of VERSION.

DLEXT
Specifies the extension of the module's loadable object. For example:

DLEXT => 'unusual_ext', # Default value is $Config{so}

NOTE: When using this option to alter the extension of a module's loadable object, it is also necessary
that the module's pm file specifies the same change:

local $DynaLoader::dl_dlext = 'unusual_ext';

DL_FUNCS
Hashref of symbol names for routines to be made available as universal symbols. Each key/value pair
consists of the package name and an array of routine names in that package. Used only under AIX, OS/2,
VMS and Win32 at present. The routine names supplied will be expanded in the same way as XSUB names
are expanded by the XS() macro. Defaults to

{"$(NAME)" => ["boot_$(NAME)" ] }

e.g.

{"RPC" => [qw( boot_rpcb rpcb_gettime getnetconfigent )],
"NetconfigPtr" => [ 'DESTROY'] }

Please see the ExtUtils::Mksymlists documentation for more information about the DL_FUNCS, DL_VARS and
FUNCLIST attributes.

DL_VARS
Array of symbol names for variables to be made available as universal symbols. Used only under AIX,
OS/2, VMS and Win32 at present. Defaults to []. (e.g. [ qw(Foo_version Foo_numstreams Foo_tree ) ])

EXCLUDE_EXT
Array of extension names to exclude when doing a static build. This is ignored if INCLUDE_EXT is
present. Consult INCLUDE_EXT for more details. (e.g. [ qw( Socket POSIX ) ] )

This attribute may be most useful when specified as a string on the command line: perl Makefile.PL
EXCLUDE_EXT='Socket Safe'

EXE_FILES
Ref to array of executable files. The files will be copied to the INST_SCRIPT directory. Make realclean
will delete them from there again.

If your executables start with something like #!perl or #!/usr/bin/perl MakeMaker will change this to
the path of the perl 'Makefile.PL' was invoked with so the programs will be sure to run properly even
if perl is not in /usr/bin/perl.

FIRST_MAKEFILE
The name of the Makefile to be produced. This is used for the second Makefile that will be produced
for the MAP_TARGET.

Defaults to 'Makefile' or 'Descrip.MMS' on VMS.

(Note: we couldn't use MAKEFILE because dmake uses this for something else).

FULLPERL
Perl binary able to run this extension, load XS modules, etc...

FULLPERLRUN
Like PERLRUN, except it uses FULLPERL.

FULLPERLRUNINST
Like PERLRUNINST, except it uses FULLPERL.

FUNCLIST
This provides an alternate means to specify function names to be exported from the extension. Its
value is a reference to an array of function names to be exported by the extension. These names are
passed through unaltered to the linker options file.

H Ref to array of *.h file names. Similar to C.

IMPORTS
This attribute is used to specify names to be imported into the extension. Takes a hash ref.

It is only used on OS/2 and Win32.

INC
Include file dirs eg: "-I/usr/5include -I/path/to/inc"

INCLUDE_EXT
Array of extension names to be included when doing a static build. MakeMaker will normally build with
all of the installed extensions when doing a static build, and that is usually the desired behavior.
If INCLUDE_EXT is present then MakeMaker will build only with those extensions which are explicitly
mentioned. (e.g. [ qw( Socket POSIX ) ])

It is not necessary to mention DynaLoader or the current extension when filling in INCLUDE_EXT. If the
INCLUDE_EXT is mentioned but is empty then only DynaLoader and the current extension will be included
in the build.

This attribute may be most useful when specified as a string on the command line: perl Makefile.PL
INCLUDE_EXT='POSIX Socket Devel::Peek'

INSTALLARCHLIB
Used by 'make install', which copies files from INST_ARCHLIB to this directory if INSTALLDIRS is set to
perl.

INSTALLBIN
Directory to install binary files (e.g. tkperl) into if INSTALLDIRS=perl.

INSTALLDIRS
Determines which of the sets of installation directories to choose: perl, site or vendor. Defaults to
site.

INSTALLMAN1DIR
INSTALLMAN3DIR
These directories get the man pages at 'make install' time if INSTALLDIRS=perl. Defaults to
$Config{installman*dir}.

If set to 'none', no man pages will be installed.

INSTALLPRIVLIB
Used by 'make install', which copies files from INST_LIB to this directory if INSTALLDIRS is set to
perl.

Defaults to $Config{installprivlib}.

INSTALLSCRIPT
Available in version 6.30_02 and above.

Used by 'make install' which copies files from INST_SCRIPT to this directory if INSTALLDIRS=perl.

INSTALLSITEARCH
Used by 'make install', which copies files from INST_ARCHLIB to this directory if INSTALLDIRS is set to
site (default).

INSTALLSITEBIN
Used by 'make install', which copies files from INST_BIN to this directory if INSTALLDIRS is set to
site (default).

INSTALLSITELIB
Used by 'make install', which copies files from INST_LIB to this directory if INSTALLDIRS is set to
site (default).

INSTALLSITEMAN1DIR
INSTALLSITEMAN3DIR
These directories get the man pages at 'make install' time if INSTALLDIRS=site (default). Defaults to
$(SITEPREFIX)/man/man$(MAN*EXT).

If set to 'none', no man pages will be installed.

INSTALLSITESCRIPT
Used by 'make install' which copies files from INST_SCRIPT to this directory if INSTALLDIRS is set to
site (default).

INSTALLVENDORARCH
Used by 'make install', which copies files from INST_ARCHLIB to this directory if INSTALLDIRS is set to
vendor. Note that if you do not set this, the value of INSTALLVENDORLIB will be used, which is probably
not what you want.

INSTALLVENDORBIN
Used by 'make install', which copies files from INST_BIN to this directory if INSTALLDIRS is set to
vendor.

INSTALLVENDORLIB
Used by 'make install', which copies files from INST_LIB to this directory if INSTALLDIRS is set to
vendor.

INSTALLVENDORMAN1DIR
INSTALLVENDORMAN3DIR
These directories get the man pages at 'make install' time if INSTALLDIRS=vendor. Defaults to
$(VENDORPREFIX)/man/man$(MAN*EXT).

If set to 'none', no man pages will be installed.

INSTALLVENDORSCRIPT
Available in version 6.30_02 and above.

Used by 'make install' which copies files from INST_SCRIPT to this directory if INSTALLDIRS is set to
vendor.

INST_ARCHLIB
Same as INST_LIB for architecture dependent files.

INST_BIN
Directory to put real binary files during 'make'. These will be copied to INSTALLBIN during 'make
install'

INST_LIB
Directory where we put library files of this extension while building it.

INST_MAN1DIR
Directory to hold the man pages at 'make' time

INST_MAN3DIR
Directory to hold the man pages at 'make' time

INST_SCRIPT
Directory where executable files should be installed during 'make'. Defaults to "./blib/script", just
to have a dummy location during testing. make install will copy the files in INST_SCRIPT to
INSTALLSCRIPT.

LD
Program to be used to link libraries for dynamic loading.

Defaults to $Config{ld}.

LDDLFLAGS
Any special flags that might need to be passed to ld to create a shared library suitable for dynamic
loading. It is up to the makefile to use it. (See "lddlflags" in Config)

Defaults to $Config{lddlflags}.

LDFROM
Defaults to "$(OBJECT)" and is used in the ld command to specify what files to link/load from (also see
dynamic_lib below for how to specify ld flags)

LIB
LIB should only be set at "perl Makefile.PL" time but is allowed as a MakeMaker argument. It has the
effect of setting both INSTALLPRIVLIB and INSTALLSITELIB to that value regardless any explicit setting
of those arguments (or of PREFIX). INSTALLARCHLIB and INSTALLSITEARCH are set to the corresponding
architecture subdirectory.

LIBPERL_A
The filename of the perllibrary that will be used together with this extension. Defaults to libperl.a.

LIBS
An anonymous array of alternative library specifications to be searched for (in order) until at least
one library is found. E.g.

'LIBS' => ["-lgdbm", "-ldbm -lfoo", "-L/path -ldbm.nfs"]

Mind, that any element of the array contains a complete set of arguments for the ld command. So do not
specify

'LIBS' => ["-ltcl", "-ltk", "-lX11"]

See ODBM_File/Makefile.PL for an example, where an array is needed. If you specify a scalar as in

'LIBS' => "-ltcl -ltk -lX11"

MakeMaker will turn it into an array with one element.

LICENSE
Available in version 6.31 and above.

The licensing terms of your distribution. Generally it's "perl_5" for the same license as Perl itself.

See CPAN::Meta::Spec for the list of options.

Defaults to "unknown".

LINKTYPE
'static' or 'dynamic' (default unless usedl=undef in config.sh). Should only be used to force static
linking (also see linkext below).

MAGICXS
Available in version 6.8305 and above.

When this is set to 1, "OBJECT" will be automagically derived from "O_FILES".

MAKE
Available in version 6.30_01 and above.

Variant of make you intend to run the generated Makefile with. This parameter lets Makefile.PL know
what make quirks to account for when generating the Makefile.

MakeMaker also honors the MAKE environment variable. This parameter takes precedence.

Currently the only significant values are 'dmake' and 'nmake' for Windows users, instructing MakeMaker
to generate a Makefile in the flavour of DMake ("Dennis Vadura's Make") or Microsoft NMake
respectively.

Defaults to $Config{make}, which may go looking for a Make program in your environment.

How are you supposed to know what flavour of Make a Makefile has been generated for if you didn't
specify a value explicitly? Search the generated Makefile for the definition of the MAKE variable,
which is used to recursively invoke the Make utility. That will tell you what Make you're supposed to
invoke the Makefile with.

MAKEAPERL
Boolean which tells MakeMaker that it should include the rules to make a perl. This is handled
automatically as a switch by MakeMaker. The user normally does not need it.

MAKEFILE_OLD
When 'make clean' or similar is run, the $(FIRST_MAKEFILE) will be backed up at this location.

Defaults to $(FIRST_MAKEFILE).old or $(FIRST_MAKEFILE)_old on VMS.

MAN1PODS
Hashref of pod-containing files. MakeMaker will default this to all EXE_FILES files that include POD
directives. The files listed here will be converted to man pages and installed as was requested at
Configure time.

This hash should map POD files (or scripts containing POD) to the man file names under the "blib/man1/"
directory, as in the following example:

MAN1PODS => {
'doc/command.pod' => 'blib/man1/command.1',
'scripts/script.pl' => 'blib/man1/script.1',
}

MAN3PODS
Hashref that assigns to *.pm and *.pod files the files into which the manpages are to be written.
MakeMaker parses all *.pod and *.pm files for POD directives. Files that contain POD will be the
default keys of the MAN3PODS hashref. These will then be converted to man pages during "make" and will
be installed during "make install".

Example similar to MAN1PODS.

MAP_TARGET
If it is intended that a new perl binary be produced, this variable may hold a name for that binary.
Defaults to perl

META_ADD
META_MERGE
Available in version 6.46 and above.

A hashref of items to add to the CPAN Meta file (META.yml or META.json).

They differ in how they behave if they have the same key as the default metadata. META_ADD will
override the default value with its own. META_MERGE will merge its value with the default.

Unless you want to override the defaults, prefer META_MERGE so as to get the advantage of any future
defaults.

Where prereqs are concerned, if META_MERGE is used, prerequisites are merged with their counterpart
WriteMakefile() argument (PREREQ_PM is merged into {prereqs}{runtime}{requires}, BUILD_REQUIRES into
"{prereqs}{build}{requires}", CONFIGURE_REQUIRES into "{prereqs}{configure}{requires}", and
TEST_REQUIRES into "{prereqs}{test}{requires})". When prereqs are specified with META_ADD, the only
prerequisites added to the file come from the metadata, not WriteMakefile() arguments.

Note that these configuration options are only used for generating META.yml and META.json -- they are
NOT used for MYMETA.yml and MYMETA.json. Therefore data in these fields should NOT be used for dynamic
(user-side) configuration.

By default CPAN Meta specification 1.4 is used. In order to use CPAN Meta specification 2.0, indicate
with "meta-spec" the version you want to use.

META_MERGE => {

"meta-spec" => { version => 2 },

resources => {

repository => {
type => 'git',
url => 'git://github.com/Perl-Toolchain-Gang/ExtUtils-MakeMaker.git',
web => 'https://github.com/Perl-Toolchain-Gang/ExtUtils-MakeMaker',
},

MIN_PERL_VERSION
Available in version 6.48 and above.

The minimum required version of Perl for this distribution.

Either the 5.006001 or the 5.6.1 format is acceptable.

MYEXTLIB
If the extension links to a library that it builds, set this to the name of the library (see SDBM_File)

NAME
The package representing the distribution. For example, "Test::More" or "ExtUtils::MakeMaker". It will
be used to derive information about the distribution such as the "DISTNAME", installation locations
within the Perl library and where XS files will be looked for by default (see "XS").

"NAME" must be a valid Perl package name and it must have an associated ".pm" file. For example,
"Foo::Bar" is a valid "NAME" and there must exist Foo/Bar.pm. Any XS code should be in Bar.xs unless
stated otherwise.

Your distribution must have a "NAME".

NEEDS_LINKING
MakeMaker will figure out if an extension contains linkable code anywhere down the directory tree, and
will set this variable accordingly, but you can speed it up a very little bit if you define this
boolean variable yourself.

NOECHO
Command so make does not print the literal commands it's running.

By setting it to an empty string you can generate a Makefile that prints all commands. Mainly used in
debugging MakeMaker itself.

Defaults to "@".

NORECURS
Boolean. Attribute to inhibit descending into subdirectories.

NO_META
When true, suppresses the generation and addition to the MANIFEST of the META.yml and META.json module
meta-data files during 'make distdir'.

Defaults to false.

NO_MYMETA
Available in version 6.57_02 and above.

When true, suppresses the generation of MYMETA.yml and MYMETA.json module meta-data files during 'perl
Makefile.PL'.

Defaults to false.

NO_PACKLIST
Available in version 6.7501 and above.

When true, suppresses the writing of "packlist" files for installs.

Defaults to false.

NO_PERLLOCAL
Available in version 6.7501 and above.

When true, suppresses the appending of installations to "perllocal".

Defaults to false.

NO_VC
In general, any generated Makefile checks for the current version of MakeMaker and the version the
Makefile was built under. If NO_VC is set, the version check is neglected. Do not write this into your
Makefile.PL, use it interactively instead.

OBJECT
List of object files, defaults to '$(BASEEXT)$(OBJ_EXT)', but can be a long string or an array
containing all object files, e.g. "tkpBind.o tkpButton.o tkpCanvas.o" or ["tkpBind.o", "tkpButton.o",
"tkpCanvas.o"]

(Where BASEEXT is the last component of NAME, and OBJ_EXT is $Config{obj_ext}.)

OPTIMIZE
Defaults to "-O". Set it to "-g" to turn debugging on. The flag is passed to subdirectory makes.

PERL
Perl binary for tasks that can be done by miniperl. If it contains spaces or other shell
metacharacters, it needs to be quoted in a way that protects them, since this value is intended to be
inserted in a shell command line in the Makefile. E.g.:

# Perl executable lives in "C:/Program Files/Perl/bin"
# Normally you don't need to set this yourself!
$ perl Makefile.PL PERL='"C:/Program Files/Perl/bin/perl.exe" -w'

PERL_CORE
Set only when MakeMaker is building the extensions of the Perl core distribution.

PERLMAINCC
The call to the program that is able to compile perlmain.c. Defaults to $(CC).

PERL_ARCHLIB
Same as for PERL_LIB, but for architecture dependent files.

Used only when MakeMaker is building the extensions of the Perl core distribution (because normally
$(PERL_ARCHLIB) is automatically in @INC, and adding it would get in the way of PERL5LIB).

PERL_LIB
Directory containing the Perl library to use.

Used only when MakeMaker is building the extensions of the Perl core distribution (because normally
$(PERL_LIB) is automatically in @INC, and adding it would get in the way of PERL5LIB).

PERL_MALLOC_OK
defaults to 0. Should be set to TRUE if the extension can work with the memory allocation routines
substituted by the Perl malloc() subsystem. This should be applicable to most extensions with
exceptions of those

• with bugs in memory allocations which are caught by Perl's malloc();

• which interact with the memory allocator in other ways than via malloc(), realloc(), free(),
calloc(), sbrk() and brk();

• which rely on special alignment which is not provided by Perl's malloc().

NOTE. Neglecting to set this flag in any one of the loaded extension nullifies many advantages of
Perl's malloc(), such as better usage of system resources, error detection, memory usage reporting,
catchable failure of memory allocations, etc.

PERLPREFIX
Directory under which core modules are to be installed.

Defaults to $Config{installprefixexp}, falling back to $Config{installprefix}, $Config{prefixexp} or
$Config{prefix} should $Config{installprefixexp} not exist.

Overridden by PREFIX.

PERLRUN
Use this instead of $(PERL) when you wish to run perl. It will set up extra necessary flags for you.

PERLRUNINST
Use this instead of $(PERL) when you wish to run perl to work with modules. It will add things like
-I$(INST_ARCH) and other necessary flags so perl can see the modules you're about to install.

PERL_SRC
Directory containing the Perl source code (use of this should be avoided, it may be undefined)

PERM_DIR
Available in version 6.51_01 and above.

Desired permission for directories. Defaults to 755.

PERM_RW
Desired permission for read/writable files. Defaults to 644.

PERM_RWX
Desired permission for executable files. Defaults to 755.

PL_FILES
MakeMaker can run programs to generate files for you at build time. By default any file named *.PL
(except Makefile.PL and Build.PL) in the top level directory will be assumed to be a Perl program and
run passing its own basename in as an argument. This basename is actually a build target, and there is
an intention, but not a requirement, that the *.PL file make the file passed to to as an argument. For
example...

perl foo.PL foo

This behavior can be overridden by supplying your own set of files to search. PL_FILES accepts a hash
ref, the key being the file to run and the value is passed in as the first argument when the PL file is
run.

PL_FILES => {'bin/foobar.PL' => 'bin/foobar'}

PL_FILES => {'foo.PL' => 'foo.c'}

Would run bin/foobar.PL like this:

perl bin/foobar.PL bin/foobar

If multiple files from one program are desired an array ref can be used.

PL_FILES => {'bin/foobar.PL' => [qw(bin/foobar1 bin/foobar2)]}

In this case the program will be run multiple times using each target file.

perl bin/foobar.PL bin/foobar1
perl bin/foobar.PL bin/foobar2

If an output file depends on extra input files beside the script itself, a hash ref can be used in
version 7.36 and above:

PL_FILES => { 'foo.PL' => {
'foo.out' => 'foo.in',
'bar.out' => [qw(bar1.in bar2.in)],
}

In this case the extra input files will be passed to the program after the target file:

perl foo.PL foo.out foo.in
perl foo.PL bar.out bar1.in bar2.in

PL files are normally run after pm_to_blib and include INST_LIB and INST_ARCH in their @INC, so the
just built modules can be accessed... unless the PL file is making a module (or anything else in PM) in
which case it is run before pm_to_blib and does not include INST_LIB and INST_ARCH in its @INC. This
apparently odd behavior is there for backwards compatibility (and it's somewhat DWIM). The argument
passed to the .PL is set up as a target to build in the Makefile. In other sections such as
"postamble" you can specify a dependency on the filename/argument that the .PL is supposed (or will
have, now that that is is a dependency) to generate. Note the file to be generated will still be
generated and the .PL will still run even without an explicit dependency created by you, since the
"all" target still depends on running all eligible to run.PL files.

PM
Hashref of .pm files and *.pl files to be installed. e.g.

{'name_of_file.pm' => '$(INST_LIB)/install_as.pm'}

By default this will include *.pm and *.pl and the files found in the PMLIBDIRS directories. Defining
PM in the Makefile.PL will override PMLIBDIRS.

PMLIBDIRS
Ref to array of subdirectories containing library files. Defaults to [ 'lib', $(BASEEXT) ]. The
directories will be scanned and any files they contain will be installed in the corresponding location
in the library. A libscan() method can be used to alter the behaviour. Defining PM in the Makefile.PL
will override PMLIBDIRS.

(Where BASEEXT is the last component of NAME.)

PM_FILTER
A filter program, in the traditional Unix sense (input from stdin, output to stdout) that is passed on
each .pm file during the build (in the pm_to_blib() phase). It is empty by default, meaning no
filtering is done. You could use:

PM_FILTER => 'perl -ne "print unless /^\\#/"',

to remove all the leading comments on the fly during the build. In order to be as portable as
possible, please consider using a Perl one-liner rather than Unix (or other) utilities, as above. The
# is escaped for the Makefile, since what is going to be generated will then be:

PM_FILTER = perl -ne "print unless /^\#/"

Without the \ before the #, we'd have the start of a Makefile comment, and the macro would be
incorrectly defined.

You will almost certainly be better off using the "PL_FILES" system, instead. See above, or the
ExtUtils::MakeMaker::FAQ entry.

POLLUTE
Prior to 5.6 various interpreter variables were available without a "PL_" prefix, eg. "PL_undef" was
available as "undef". As of release 5.6, these are only defined if the POLLUTE flag is enabled:

perl Makefile.PL POLLUTE=1

Please inform the module author if this is necessary to successfully install a module under 5.6 or
later.

PPM_INSTALL_EXEC
Name of the executable used to run "PPM_INSTALL_SCRIPT" below. (e.g. perl)

PPM_INSTALL_SCRIPT
Name of the script that gets executed by the Perl Package Manager after the installation of a package.

PPM_UNINSTALL_EXEC
Available in version 6.8502 and above.

Name of the executable used to run "PPM_UNINSTALL_SCRIPT" below. (e.g. perl)

PPM_UNINSTALL_SCRIPT
Available in version 6.8502 and above.

Name of the script that gets executed by the Perl Package Manager before the removal of a package.

PREFIX
This overrides all the default install locations. Man pages, libraries, scripts, etc... MakeMaker
will try to make an educated guess about where to place things under the new PREFIX based on your
Config defaults. Failing that, it will fall back to a structure which should be sensible for your
platform.

If you specify LIB or any INSTALL* variables they will not be affected by the PREFIX.

PREREQ_FATAL
Bool. If this parameter is true, failing to have the required modules (or the right versions thereof)
will be fatal. "perl Makefile.PL" will "die" instead of simply informing the user of the missing
dependencies.

It is extremely rare to have to use "PREREQ_FATAL". Its use by module authors is strongly discouraged
and should never be used lightly.

For dependencies that are required in order to run "Makefile.PL", see "CONFIGURE_REQUIRES".

Module installation tools have ways of resolving unmet dependencies but to do that they need a
Makefile. Using "PREREQ_FATAL" breaks this. That's bad.

Assuming you have good test coverage, your tests should fail with missing dependencies informing the
user more strongly that something is wrong. You can write a t/00compile.t test which will simply check
that your code compiles and stop "make test" prematurely if it doesn't. See "BAIL_OUT" in Test::More
for more details.

PREREQ_PM
A hash of modules that are needed to run your module. The keys are the module names ie. Test::More,
and the minimum version is the value. If the required version number is 0 any version will do. The
versions given may be a Perl v-string (see version) or a range (see CPAN::Meta::Requirements).

This will go into the "requires" field of your META.yml and the "runtime" of the "prereqs" field of
your META.json.

PREREQ_PM => {
# Require Test::More at least 0.47
"Test::More" => "0.47",

# Require any version of Acme::Buffy
"Acme::Buffy" => 0,
}

PREREQ_PRINT
Bool. If this parameter is true, the prerequisites will be printed to stdout and MakeMaker will exit.
The output format is an evalable hash ref.

$PREREQ_PM = {
'A::B' => Vers1,
'C::D' => Vers2,
...
};

If a distribution defines a minimal required perl version, this is added to the output as an additional
line of the form:

$MIN_PERL_VERSION = '5.008001';

If BUILD_REQUIRES is not empty, it will be dumped as $BUILD_REQUIRES hashref.

PRINT_PREREQ
RedHatism for "PREREQ_PRINT". The output format is different, though:

perl(A::B)>=Vers1 perl(C::D)>=Vers2 ...

A minimal required perl version, if present, will look like this:

perl(perl)>=5.008001

SITEPREFIX
Like PERLPREFIX, but only for the site install locations.

Defaults to $Config{siteprefixexp}. Perls prior to 5.6.0 didn't have an explicit siteprefix in the
Config. In those cases $Config{installprefix} will be used.

Overridable by PREFIX

SIGN
Available in version 6.18 and above.

When true, perform the generation and addition to the MANIFEST of the SIGNATURE file in the distdir
during 'make distdir', via 'cpansign -s'.

Note that you need to install the Module::Signature module to perform this operation.

Defaults to false.

SKIP
Arrayref. E.g. [qw(name1 name2)] skip (do not write) sections of the Makefile. Caution! Do not use the
SKIP attribute for the negligible speedup. It may seriously damage the resulting Makefile. Only use it
if you really need it.

TEST_REQUIRES
Available in version 6.64 and above.

A hash of modules that are needed to test your module but not run or build it.

This will go into the "build_requires" field of your META.yml and the "test" of the "prereqs" field of
your META.json.

The format is the same as PREREQ_PM.

TYPEMAPS
Ref to array of typemap file names. Use this when the typemaps are in some directory other than the
current directory or when they are not named typemap. The last typemap in the list takes precedence.
A typemap in the current directory has highest precedence, even if it isn't listed in TYPEMAPS. The
default system typemap has lowest precedence.

VENDORPREFIX
Like PERLPREFIX, but only for the vendor install locations.

Defaults to $Config{vendorprefixexp}.

Overridable by PREFIX

VERBINST
If true, make install will be verbose

VERSION
Your version number for distributing the package. This defaults to 0.1.

VERSION_FROM
Instead of specifying the VERSION in the Makefile.PL you can let MakeMaker parse a file to determine
the version number. The parsing routine requires that the file named by VERSION_FROM contains one
single line to compute the version number. The first line in the file that contains something like a
$VERSION assignment or "package Name VERSION" will be used. The following lines will be parsed o.k.:

# Good
package Foo::Bar 1.23; # 1.23
$VERSION = '1.00'; # 1.00
*VERSION = \'1.01'; # 1.01
($VERSION) = q$Revision$ =~ /(\d+)/g; # The digits in $Revision$
$FOO::VERSION = '1.10'; # 1.10
*FOO::VERSION = \'1.11'; # 1.11

but these will fail:

# Bad
my $VERSION = '1.01';
local $VERSION = '1.02';
local $FOO::VERSION = '1.30';

(Putting "my" or "local" on the preceding line will work o.k.)

"Version strings" are incompatible and should not be used.

# Bad
$VERSION = 1.2.3;
$VERSION = v1.2.3;

version objects are fine. As of MakeMaker 6.35 version.pm will be automatically loaded, but you must
declare the dependency on version.pm. For compatibility with older MakeMaker you should load on the
same line as $VERSION is declared.

# All on one line
use version; our $VERSION = qv(1.2.3);

The file named in VERSION_FROM is not added as a dependency to Makefile. This is not really correct,
but it would be a major pain during development to have to rewrite the Makefile for any smallish change
in that file. If you want to make sure that the Makefile contains the correct VERSION macro after any
change of the file, you would have to do something like

depend => { Makefile => '$(VERSION_FROM)' }

See attribute "depend" below.

VERSION_SYM
A sanitized VERSION with . replaced by _. For places where . has special meaning (some filesystems,
RCS labels, etc...)

XS
Hashref of .xs files. MakeMaker will default this. e.g.

{'name_of_file.xs' => 'name_of_file.c'}

The .c files will automatically be included in the list of files deleted by a make clean.

XSBUILD
Available in version 7.12 and above.

Hashref with options controlling the operation of "XSMULTI":

{
xs => {
all => {
# options applying to all .xs files for this distribution
},
'lib/Class/Name/File' => { # specifically for this file
DEFINE => '-Dfunktastic', # defines for only this file
INC => "-I$funkyliblocation", # include flags for only this file
# OBJECT => 'lib/Class/Name/File$(OBJ_EXT)', # default
LDFROM => "lib/Class/Name/File\$(OBJ_EXT) $otherfile\$(OBJ_EXT)", # what's linked
},
},
}

Note "xs" is the file-extension. More possibilities may arise in the future. Note that object names are
specified without their XS extension.

"LDFROM" defaults to the same as "OBJECT". "OBJECT" defaults to, for "XSMULTI", just the XS filename
with the extension replaced with the compiler-specific object-file extension.

The distinction between "OBJECT" and "LDFROM": "OBJECT" is the make target, so make will try to build
it. However, "LDFROM" is what will actually be linked together to make the shared object or static
library (SO/SL), so if you override it, make sure it includes what you want to make the final SO/SL,
almost certainly including the XS basename with "$(OBJ_EXT)" appended.

XSMULTI
Available in version 7.12 and above.

When this is set to 1, multiple XS files may be placed under lib/ next to their corresponding "*.pm"
files (this is essential for compiling with the correct "VERSION" values). This feature should be
considered experimental, and details of it may change.

This feature was inspired by, and small portions of code copied from, ExtUtils::MakeMaker::BigHelper.
Hopefully this feature will render that module mainly obsolete.

XSOPT
String of options to pass to xsubpp. This might include "-C++" or "-extern". Do not include typemaps
here; the TYPEMAP parameter exists for that purpose.

XSPROTOARG
May be set to "-prototypes", "-noprototypes" or the empty string. The empty string is equivalent to
the xsubpp default, or "-noprototypes". See the xsubpp documentation for details. MakeMaker defaults
to the empty string.

XS_VERSION
Your version number for the .xs file of this package. This defaults to the value of the VERSION
attribute.

Additional lowercase attributes
can be used to pass parameters to the methods which implement that part of the Makefile. Parameters are
specified as a hash ref but are passed to the method as a hash.

clean
{FILES => "*.xyz foo"}

depend
{ANY_TARGET => ANY_DEPENDENCY, ...}

(ANY_TARGET must not be given a double-colon rule by MakeMaker.)

dist
{TARFLAGS => 'cvfF', COMPRESS => 'gzip', SUFFIX => '.gz',
SHAR => 'shar -m', DIST_CP => 'ln', ZIP => '/bin/zip',
ZIPFLAGS => '-rl', DIST_DEFAULT => 'private tardist' }

If you specify COMPRESS, then SUFFIX should also be altered, as it is needed to tell make the target
file of the compression. Setting DIST_CP to ln can be useful, if you need to preserve the timestamps on
your files. DIST_CP can take the values 'cp', which copies the file, 'ln', which links the file, and
'best' which copies symbolic links and links the rest. Default is 'best'.

dynamic_lib
{ARMAYBE => 'ar', OTHERLDFLAGS => '...', INST_DYNAMIC_DEP => '...'}

linkext
{LINKTYPE => 'static', 'dynamic' or ''}

NB: Extensions that have nothing but *.pm files had to say

{LINKTYPE => ''}

with Pre-5.0 MakeMakers. Since version 5.00 of MakeMaker such a line can be deleted safely. MakeMaker
recognizes when there's nothing to be linked.

macro
{ANY_MACRO => ANY_VALUE, ...}

postamble
Anything put here will be passed to MY::postamble() if you have one.

realclean
{FILES => '$(INST_ARCHAUTODIR)/*.xyz'}

test
Specify the targets for testing.

{TESTS => 't/*.t'}

"RECURSIVE_TEST_FILES" can be used to include all directories recursively under "t" that contain ".t"
files. It will be ignored if you provide your own "TESTS" attribute, defaults to false.

{RECURSIVE_TEST_FILES=>1}

This is supported since 6.76

tool_autosplit
{MAXLEN => 8}

Overriding MakeMaker Methods
If you cannot achieve the desired Makefile behaviour by specifying attributes you may define private
subroutines in the Makefile.PL. Each subroutine returns the text it wishes to have written to the
Makefile. To override a section of the Makefile you can either say:

sub MY::c_o { "new literal text" }

or you can edit the default by saying something like:

package MY; # so that "SUPER" works right
sub c_o {
my $inherited = shift->SUPER::c_o(@_);
$inherited =~ s/old text/new text/;
$inherited;
}

If you are running experiments with embedding perl as a library into other applications, you might find
MakeMaker is not sufficient. You'd better have a look at ExtUtils::Embed which is a collection of
utilities for embedding.

If you still need a different solution, try to develop another subroutine that fits your needs and submit
the diffs to "makemaker@perl.org"

For a complete description of all MakeMaker methods see ExtUtils::MM_Unix.

Here is a simple example of how to add a new target to the generated Makefile:

sub MY::postamble {
return <<'MAKE_FRAG';
$(MYEXTLIB): sdbm/Makefile
cd sdbm && $(MAKE) all

MAKE_FRAG
}

The End Of Cargo Cult Programming
WriteMakefile() now does some basic sanity checks on its parameters to protect against typos and
malformatted values. This means some things which happened to work in the past will now throw warnings
and possibly produce internal errors.

Some of the most common mistakes:

"MAN3PODS => ' '"
This is commonly used to suppress the creation of man pages. MAN3PODS takes a hash ref not a string,
but the above worked by accident in old versions of MakeMaker.

The correct code is "MAN3PODS => { }".

Hintsfile support
MakeMaker.pm uses the architecture-specific information from Config.pm. In addition it evaluates
architecture specific hints files in a "hints/" directory. The hints files are expected to be named like
their counterparts in "PERL_SRC/hints", but with an ".pl" file name extension (eg. "next_3_2.pl"). They
are simply "eval"ed by MakeMaker within the WriteMakefile() subroutine, and can be used to execute
commands as well as to include special variables. The rules which hintsfile is chosen are the same as in
Configure.

The hintsfile is eval()ed immediately after the arguments given to WriteMakefile are stuffed into a hash
reference $self but before this reference becomes blessed. So if you want to do the equivalent to
override or create an attribute you would say something like

$self->{LIBS} = ['-ldbm -lucb -lc'];

Distribution Support
For authors of extensions MakeMaker provides several Makefile targets. Most of the support comes from the
ExtUtils::Manifest module, where additional documentation can be found.

make distcheck
reports which files are below the build directory but not in the MANIFEST file and vice versa. (See
"fullcheck" in ExtUtils::Manifest for details)

make skipcheck
reports which files are skipped due to the entries in the "MANIFEST.SKIP" file (See "skipcheck" in
ExtUtils::Manifest for details)

make distclean
does a realclean first and then the distcheck. Note that this is not needed to build a new
distribution as long as you are sure that the MANIFEST file is ok.

make veryclean
does a realclean first and then removes backup files such as "*~", "*.bak", "*.old" and "*.orig"

make manifest
rewrites the MANIFEST file, adding all remaining files found (See "mkmanifest" in ExtUtils::Manifest
for details)

make distdir
Copies all the files that are in the MANIFEST file to a newly created directory with the name
"$(DISTNAME)-$(VERSION)". If that directory exists, it will be removed first.

Additionally, it will create META.yml and META.json module meta-data file in the distdir and add this
to the distdir's MANIFEST. You can shut this behavior off with the NO_META flag.

make disttest
Makes a distdir first, and runs a "perl Makefile.PL", a make, and a make test in that directory.

make tardist
First does a distdir. Then a command $(PREOP) which defaults to a null command, followed by
$(TO_UNIX), which defaults to a null command under UNIX, and will convert files in distribution
directory to UNIX format otherwise. Next it runs "tar" on that directory into a tarfile and deletes
the directory. Finishes with a command $(POSTOP) which defaults to a null command.

make dist
Defaults to $(DIST_DEFAULT) which in turn defaults to tardist.

make uutardist
Runs a tardist first and uuencodes the tarfile.

make shdist
First does a distdir. Then a command $(PREOP) which defaults to a null command. Next it runs "shar"
on that directory into a sharfile and deletes the intermediate directory again. Finishes with a
command $(POSTOP) which defaults to a null command. Note: For shdist to work properly a "shar"
program that can handle directories is mandatory.

make zipdist
First does a distdir. Then a command $(PREOP) which defaults to a null command. Runs "$(ZIP)
$(ZIPFLAGS)" on that directory into a zipfile. Then deletes that directory. Finishes with a command
$(POSTOP) which defaults to a null command.

make ci
Does a $(CI) and a $(RCS_LABEL) on all files in the MANIFEST file.

Customization of the dist targets can be done by specifying a hash reference to the dist attribute of the
WriteMakefile call. The following parameters are recognized:

CI ('ci -u')
COMPRESS ('gzip --best')
POSTOP ('@ :')
PREOP ('@ :')
TO_UNIX (depends on the system)
RCS_LABEL ('rcs -q -Nv$(VERSION_SYM):')
SHAR ('shar')
SUFFIX ('.gz')
TAR ('tar')
TARFLAGS ('cvf')
ZIP ('zip')
ZIPFLAGS ('-r')

An example:

WriteMakefile(
...other options...
dist => {
COMPRESS => "bzip2",
SUFFIX => ".bz2"
}
);

Module Meta-Data (META and MYMETA)
Long plaguing users of MakeMaker based modules has been the problem of getting basic information about
the module out of the sources without running the Makefile.PL and doing a bunch of messy heuristics on
the resulting Makefile. Over the years, it has become standard to keep this information in one or more
CPAN Meta files distributed with each distribution.

The original format of CPAN Meta files was YAML and the corresponding file was called META.yml. In 2010,
version 2 of the CPAN::Meta::Spec was released, which mandates JSON format for the metadata in order to
overcome certain compatibility issues between YAML serializers and to avoid breaking older clients unable
to handle a new version of the spec. The CPAN::Meta library is now standard for accessing old and new-
style Meta files.

If CPAN::Meta is installed, MakeMaker will automatically generate META.json and META.yml files for you
and add them to your MANIFEST as part of the 'distdir' target (and thus the 'dist' target). This is
intended to seamlessly and rapidly populate CPAN with module meta-data. If you wish to shut this feature
off, set the "NO_META" WriteMakefile() flag to true.

At the 2008 QA Hackathon in Oslo, Perl module toolchain maintainers agreed to use the CPAN Meta format to
communicate post-configuration requirements between toolchain components. These files, MYMETA.json and
MYMETA.yml, are generated when Makefile.PL generates a Makefile (if CPAN::Meta is installed). Clients
like CPAN or CPANPLUS will read these files to see what prerequisites must be fulfilled before building
or testing the distribution. If you wish to shut this feature off, set the "NO_MYMETA" WriteMakefile()
flag to true.

Disabling an extension
If some events detected in Makefile.PL imply that there is no way to create the Module, but this is a
normal state of things, then you can create a Makefile which does nothing, but succeeds on all the
"usual" build targets. To do so, use

use ExtUtils::MakeMaker qw(WriteEmptyMakefile);
WriteEmptyMakefile();

instead of WriteMakefile().

This may be useful if other modules expect this module to be built OK, as opposed to work OK (say, this
system-dependent module builds in a subdirectory of some other distribution, or is listed as a dependency
in a CPAN::Bundle, but the functionality is supported by different means on the current architecture).

Other Handy Functions
prompt
my $value = prompt($message);
my $value = prompt($message, $default);

The prompt() function provides an easy way to request user input used to write a makefile. It
displays the $message as a prompt for input. If a $default is provided it will be used as a default.
The function returns the $value selected by the user.

If prompt() detects that it is not running interactively and there is nothing on STDIN or if the
PERL_MM_USE_DEFAULT environment variable is set to true, the $default will be used without prompting.
This prevents automated processes from blocking on user input.

If no $default is provided an empty string will be used instead.

os_unsupported
os_unsupported();
os_unsupported if $^O eq 'MSWin32';

The os_unsupported() function provides a way to correctly exit your "Makefile.PL" before calling
"WriteMakefile". It is essentially a "die" with the message "OS unsupported".

This is supported since 7.26

Supported versions of Perl
Please note that while this module works on Perl 5.6, it is no longer being routinely tested on 5.6 - the
earliest Perl version being routinely tested, and expressly supported, is 5.8.1. However, patches to
repair any breakage on 5.6 are still being accepted.

ENVIRONMENT

       PERL_MM_OPT
           Command line options used by "MakeMaker->new()", and thus by WriteMakefile().  The string is split as
           the shell would, and the result is processed before any actual command line arguments are processed.

             PERL_MM_OPT='CCFLAGS="-Wl,-rpath -Wl,/foo/bar/lib" LIBS="-lwibble -lwobble"'

       PERL_MM_USE_DEFAULT
           If set to a true value then MakeMaker's prompt function will always return the default without
           waiting for user input.

       PERL_CORE
           Same as the PERL_CORE parameter.  The parameter overrides this.

AUTHORS

       Andy Dougherty "doughera@lafayette.edu", Andreas König "andreas.koenig@mind.de", Tim Bunce
       "timb@cpan.org".  VMS support by Charles Bailey "bailey@newman.upenn.edu".  OS/2 support by Ilya
       Zakharevich "ilya@math.ohio-state.edu".

       Currently maintained by Michael G Schwern "schwern@pobox.com"

       Send patches and ideas to "makemaker@perl.org".

       Send bug reports via http://rt.cpan.org/.  Please send your generated Makefile along with your report.

       For more up-to-date information, see <https://metacpan.org/release/ExtUtils-MakeMaker>.

       Repository available at <https://github.com/Perl-Toolchain-Gang/ExtUtils-MakeMaker>.

LICENSE

       This program is free software; you can redistribute it and/or modify it under the same terms as Perl
       itself.

       See <http://www.perl.com/perl/misc/Artistic.html>

NAME

SYNOPSIS

DESCRIPTION

ENVIRONMENT

SEE ALSO

AUTHORS

LICENSE