ExtUtils::MakeMaker::FUser)Contributed Perl DocumenExtUtils::MakeMaker::FAQ(3)
NAME
ExtUtils::MakeMaker::FAQ - Frequently Asked Questions About MakeMaker
DESCRIPTION
FAQs, tricks and tips for "ExtUtils::MakeMaker".
Module Installation
How do I install a module into my home directory?
If you're not the Perl administrator you probably don't have
permission to install a module to its default location. Then you
should install it for your own use into your home directory like
so:
# Non-unix folks, replace ~ with /path/to/your/home/dir
perl Makefile.PL INSTALL_BASE=~
This will put modules into ~/lib/perl5, man pages into ~/man and
programs into ~/bin.
To ensure your Perl programs can see these newly installed modules,
set your "PERL5LIB" environment variable to ~/lib/perl5 or tell
each of your programs to look in that directory with the following:
use lib "$ENV{HOME}/lib/perl5";
or if $ENV{HOME} isn't set and you don't want to set it for some
reason, do it the long way.
use lib "/path/to/your/home/dir/lib/perl5";
How do I get MakeMaker and Module::Build to install to the same place?
Module::Build, as of 0.28, supports two ways to install to the same
location as MakeMaker.
We highly recommend the install_base method, its the simplest and
most closely approximates the expected behavior of an installation
prefix.
1) Use INSTALL_BASE / "--install_base"
MakeMaker (as of 6.31) and Module::Build (as of 0.28) both can
install to the same locations using the "install_base" concept.
See "INSTALL_BASE" in ExtUtils::MakeMaker for details. To get MM
and MB to install to the same location simply set INSTALL_BASE in
MM and "--install_base" in MB to the same location.
perl Makefile.PL INSTALL_BASE=/whatever
perl Build.PL --install_base /whatever
This works most like other language's behavior when you specify a
prefix. We recommend this method.
2) Use PREFIX / "--prefix"
Module::Build 0.28 added support for "--prefix" which works like
MakeMaker's PREFIX.
perl Makefile.PL PREFIX=/whatever
perl Build.PL --prefix /whatever
We highly discourage this method. It should only be used if you
know what you're doing and specifically need the PREFIX behavior.
The PREFIX algorithm is complicated and focused on matching the
system installation.
How do I keep from installing man pages?
Recent versions of MakeMaker will only install man pages on Unix-
like operating systems.
For an individual module:
perl Makefile.PL INSTALLMAN1DIR=none INSTALLMAN3DIR=none
If you want to suppress man page installation for all modules you
have to reconfigure Perl and tell it 'none' when it asks where to
install man pages.
How do I use a module without installing it?
Two ways. One is to build the module normally...
perl Makefile.PL
make
make test
...and then set the PERL5LIB environment variable to point at the
blib/lib and blib/arch directories.
The other is to install the module in a temporary location.
perl Makefile.PL INSTALL_BASE=~/tmp
make
make test
make install
And then set PERL5LIB to ~/tmp/lib/perl5. This works well when you
have multiple modules to work with. It also ensures that the
module goes through its full installation process which may modify
it.
PREFIX vs INSTALL_BASE from Module::Build::Cookbook
The behavior of PREFIX is complicated and depends closely on how
your Perl is configured. The resulting installation locations will
vary from machine to machine and even different installations of
Perl on the same machine. Because of this, its difficult to
document where prefix will place your modules.
In contrast, INSTALL_BASE has predictable, easy to explain
installation locations. Now that Module::Build and MakeMaker both
have INSTALL_BASE there is little reason to use PREFIX other than
to preserve your existing installation locations. If you are
starting a fresh Perl installation we encourage you to use
INSTALL_BASE. If you have an existing installation installed via
PREFIX, consider moving it to an installation structure matching
INSTALL_BASE and using that instead.
Common errors and problems
"No rule to make target `/usr/lib/perl5/CORE/config.h', needed by
`Makefile'"
Just what it says, you're missing that file. MakeMaker uses it to
determine if perl has been rebuilt since the Makefile was made.
It's a bit of a bug that it halts installation.
Some operating systems don't ship the CORE directory with their
base perl install. To solve the problem, you likely need to
install a perl development package such as perl-devel (CentOS,
Fedora and other Redhat systems) or perl (Ubuntu and other Debian
systems).
Philosophy and History
Why not just use <insert other build config tool here>?
Why did MakeMaker reinvent the build configuration wheel? Why not
just use autoconf or automake or ppm or Ant or ...
There are many reasons, but the major one is cross-platform
compatibility.
Perl is one of the most ported pieces of software ever. It works
on operating systems I've never even heard of (see perlport for
details). It needs a build tool that can work on all those
platforms and with any wacky C compilers and linkers they might
have.
No such build tool exists. Even make itself has wildly different
dialects. So we have to build our own.
What is Module::Build and how does it relate to MakeMaker?
Module::Build is a project by Ken Williams to supplant MakeMaker.
Its primary advantages are:
o pure perl. no make, no shell commands
o easier to customize
o cleaner internals
o less cruft
Module::Build is the official heir apparent to MakeMaker and we
encourage people to work on M::B rather than spending time adding
features to MakeMaker.
Module Writing
How do I keep my $VERSION up to date without resetting it manually?
Often you want to manually set the $VERSION in the main module
distribution because this is the version that everybody sees on
CPAN and maybe you want to customize it a bit. But for all the
other modules in your dist, $VERSION is really just bookkeeping and
all that's important is it goes up every time the module is
changed. Doing this by hand is a pain and you often forget.
Simplest way to do it automatically is to use your version control
system's revision number (you are using version control, right?).
In CVS, RCS and SVN you use $Revision$ (see the documentation of
your version control system for details). Every time the file is
checked in the $Revision$ will be updated, updating your $VERSION.
SVN uses a simple integer for $Revision$ so you can adapt it for
your $VERSION like so:
($VERSION) = q$Revision$ =~ /(\d+)/;
In CVS and RCS version 1.9 is followed by 1.10. Since CPAN
compares version numbers numerically we use a sprintf() to convert
1.9 to 1.009 and 1.10 to 1.010 which compare properly.
$VERSION = sprintf "%d.%03d", q$Revision$ =~ /(\d+)\.(\d+)/g;
If branches are involved (ie. $Revision: 1.5.3.4$) it's a little
more complicated.
# must be all on one line or MakeMaker will get confused.
$VERSION = do { my @r = (q$Revision$ =~ /\d+/g); sprintf "%d."."%03d" x $#r, @r };
In SVN, $Revision$ should be the same for every file in the project
so they would all have the same $VERSION. CVS and RCS have a
different $Revision$ per file so each file will have a different
$VERSION. Distributed version control systems, such as SVK, may
have a different $Revision$ based on who checks out the file,
leading to a different $VERSION on each machine! Finally, some
distributed version control systems, such as darcs, have no concept
of revision number at all.
What's this META.yml thing and how did it get in my MANIFEST?!
META.yml is a module meta-data file pioneered by Module::Build and
automatically generated as part of the 'distdir' target (and thus
'dist'). See "Module Meta-Data" in ExtUtils::MakeMaker.
To shut off its generation, pass the "NO_META" flag to
"WriteMakefile()".
How do I delete everything not in my MANIFEST?
Some folks are surprised that "make distclean" does not delete
everything not listed in their MANIFEST (thus making a clean
distribution) but only tells them what they need to delete. This
is done because it is considered too dangerous. While developing
your module you might write a new file, not add it to the MANIFEST,
then run a "distclean" and be sad because your new work was
deleted.
If you really want to do this, you can use
"ExtUtils::Manifest::manifind()" to read the MANIFEST and
File::Find to delete the files. But you have to be careful.
Here's a script to do that. Use at your own risk. Have fun
blowing holes in your foot.
#!/usr/bin/perl -w
use strict;
use File::Spec;
use File::Find;
use ExtUtils::Manifest qw(maniread);
my %manifest = map {( $_ => 1 )}
grep { File::Spec->canonpath($_) }
keys %{ maniread() };
if( !keys %manifest ) {
print "No files found in MANIFEST. Stopping.\n";
exit;
}
find({
wanted => sub {
my $path = File::Spec->canonpath($_);
return unless -f $path;
return if exists $manifest{ $path };
print "unlink $path\n";
unlink $path;
},
no_chdir => 1
},
"."
);
Which tar should I use on Windows?
We recommend ptar from Archive::Tar not older than 1.66 with '-C'
option.
Which zip should I use on Windows for '[nd]make zipdist'?
We recommend InfoZIP: <http://www.info-zip.org/Zip.html>
XS
How do I prevent "object version X.XX does not match bootstrap
parameter Y.YY" errors?
XS code is very sensitive to the module version number and will
complain if the version number in your Perl module doesn't match.
If you change your module's version # without rerunning Makefile.PL
the old version number will remain in the Makefile, causing the XS
code to be built with the wrong number.
To avoid this, you can force the Makefile to be rebuilt whenever
you change the module containing the version number by adding this
to your WriteMakefile() arguments.
depend => { '$(FIRST_MAKEFILE)' => '$(VERSION_FROM)' }
How do I make two or more XS files coexist in the same directory?
Sometimes you need to have two and more XS files in the same
package. One way to go is to put them into separate directories,
but sometimes this is not the most suitable solution. The following
technique allows you to put two (and more) XS files in the same
directory.
Let's assume that we have a package "Cool::Foo", which includes
"Cool::Foo" and "Cool::Bar" modules each having a separate XS file.
First we use the following Makefile.PL:
use ExtUtils::MakeMaker;
WriteMakefile(
NAME => 'Cool::Foo',
VERSION_FROM => 'Foo.pm',
OBJECT => q/$(O_FILES)/,
# ... other attrs ...
);
Notice the "OBJECT" attribute. MakeMaker generates the following
variables in Makefile:
# Handy lists of source code files:
XS_FILES= Bar.xs \
Foo.xs
C_FILES = Bar.c \
Foo.c
O_FILES = Bar.o \
Foo.o
Therefore we can use the "O_FILES" variable to tell MakeMaker to
use these objects into the shared library.
That's pretty much it. Now write Foo.pm and Foo.xs, Bar.pm and
Bar.xs, where Foo.pm bootstraps the shared library and Bar.pm
simply loading Foo.pm.
The only issue left is to how to bootstrap Bar.xs. This is done
from Foo.xs:
MODULE = Cool::Foo PACKAGE = Cool::Foo
BOOT:
# boot the second XS file
boot_Cool__Bar(aTHX_ cv);
If you have more than two files, this is the place where you should
boot extra XS files from.
The following four files sum up all the details discussed so far.
Foo.pm:
-------
package Cool::Foo;
require DynaLoader;
our @ISA = qw(DynaLoader);
our $VERSION = '0.01';
bootstrap Cool::Foo $VERSION;
1;
Bar.pm:
-------
package Cool::Bar;
use Cool::Foo; # bootstraps Bar.xs
1;
Foo.xs:
-------
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
MODULE = Cool::Foo PACKAGE = Cool::Foo
BOOT:
# boot the second XS file
boot_Cool__Bar(aTHX_ cv);
MODULE = Cool::Foo PACKAGE = Cool::Foo PREFIX = cool_foo_
void
cool_foo_perl_rules()
CODE:
fprintf(stderr, "Cool::Foo says: Perl Rules\n");
Bar.xs:
-------
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
MODULE = Cool::Bar PACKAGE = Cool::Bar PREFIX = cool_bar_
void
cool_bar_perl_rules()
CODE:
fprintf(stderr, "Cool::Bar says: Perl Rules\n");
And of course a very basic test:
t/cool.t:
--------
use Test;
BEGIN { plan tests => 1 };
use Cool::Foo;
use Cool::Bar;
Cool::Foo::perl_rules();
Cool::Bar::perl_rules();
ok 1;
This tip has been brought to you by Nick Ing-Simmons and Stas
Bekman.
PATCHING
If you have a question you'd like to see added to the FAQ (whether or
not you have the answer) please send it to makemaker AT perl.org.
AUTHOR
The denizens of makemaker AT perl.org.
SEE ALSO
ExtUtils::MakeMaker
perl v5.16.3 2013-06-14 ExtUtils::MakeMaker::FAQ(3)