1 package ExtUtils::MakeMaker::FAQ;
10 ExtUtils::MakeMaker::FAQ - Frequently Asked Questions About MakeMaker
14 FAQs, tricks and tips for C<ExtUtils::MakeMaker>.
17 =head2 Module Installation
21 =item How do I install a module into my home directory?
23 If you're not the Perl administrator you probably don't have
24 permission to install a module to its default location. Then you
25 should install it for your own use into your home directory like so:
27 # Non-unix folks, replace ~ with /path/to/your/home/dir
28 perl Makefile.PL INSTALL_BASE=~
30 This will put modules into F<~/lib/perl5>, man pages into F<~/man> and
31 programs into F<~/bin>.
33 To ensure your Perl programs can see these newly installed modules,
34 set your C<PERL5LIB> environment variable to F<~/lib/perl5> or tell
35 each of your programs to look in that directory with the following:
37 use lib "$ENV{HOME}/lib/perl5";
39 or if $ENV{HOME} isn't set and you don't want to set it for some
40 reason, do it the long way.
42 use lib "/path/to/your/home/dir/lib/perl5";
45 =item How do I get MakeMaker and Module::Build to install to the same place?
47 Module::Build, as of 0.28, supports two ways to install to the same
48 location as MakeMaker.
50 1) Use INSTALL_BASE / C<--install_base>
52 MakeMaker (as of 6.31) and Module::Build (as of 0.28) both can install
53 to the same locations using the "install_base" concept. See
54 L<ExtUtils::MakeMaker/INSTALL_BASE> for details. To get MM and MB to
55 install to the same location simply set INSTALL_BASE in MM and
56 C<--install_base> in MB to the same location.
58 perl Makefile.PL INSTALL_BASE=/whatever
59 perl Build.PL --install_base /whatever
61 2) Use PREFIX / C<--prefix>
63 Module::Build 0.28 added support for C<--prefix> which works like
66 perl Makefile.PL PREFIX=/whatever
67 perl Build.PL --prefix /whatever
70 =item How do I keep from installing man pages?
72 Recent versions of MakeMaker will only install man pages on Unix like
75 For an individual module:
77 perl Makefile.PL INSTALLMAN1DIR=none INSTALLMAN3DIR=none
79 If you want to suppress man page installation for all modules you have
80 to reconfigure Perl and tell it 'none' when it asks where to install
84 =item How do I use a module without installing it?
86 Two ways. One is to build the module normally...
92 ...and then set the PERL5LIB environment variable to point at the
93 blib/lib and blib/arch directories.
95 The other is to install the module in a temporary location.
97 perl Makefile.PL INSTALL_BASE=~/tmp
102 And then set PERL5LIB to F<~/tmp/lib/perl5>. This works well when you
103 have multiple modules to work with. It also ensures that the module
104 goes through its full installation process which may modify it.
106 =item PREFIX vs INSTALL_BASE from Module::Build::Cookbook
108 The behavior of PREFIX is complicated and depends closely on how your
109 Perl is configured. The resulting installation locations will vary from
110 machine to machine and even different installations of Perl on the same machine.
111 Because of this, its difficult to document where prefix will place your modules.
113 In contrast, INSTALL_BASE has predictable, easy to explain installation locations.
114 Now that Module::Build and MakeMaker both have INSTALL_BASE there is little reason
115 to use PREFIX other than to preserve your existing installation locations. If you
116 are starting a fresh Perl installation we encourage you to use INSTALL_BASE. If
117 you have an existing installation installed via PREFIX, consider moving it to an
118 installation structure matching INSTALL_BASE and using that instead.
123 =head2 Philosophy and History
127 =item Why not just use <insert other build config tool here>?
129 Why did MakeMaker reinvent the build configuration wheel? Why not
130 just use autoconf or automake or ppm or Ant or ...
132 There are many reasons, but the major one is cross-platform
135 Perl is one of the most ported pieces of software ever. It works on
136 operating systems I've never even heard of (see perlport for details).
137 It needs a build tool that can work on all those platforms and with
138 any wacky C compilers and linkers they might have.
140 No such build tool exists. Even make itself has wildly different
141 dialects. So we have to build our own.
144 =item What is Module::Build and how does it relate to MakeMaker?
146 Module::Build is a project by Ken Williams to supplant MakeMaker.
147 Its primary advantages are:
151 =item * pure perl. no make, no shell commands
153 =item * easier to customize
155 =item * cleaner internals
161 Module::Build is the official heir apparent to MakeMaker and we
162 encourage people to work on M::B rather than spending time adding features
168 =head2 Module Writing
172 =item How do I keep my $VERSION up to date without resetting it manually?
174 Often you want to manually set the $VERSION in the main module
175 distribution because this is the version that everybody sees on CPAN
176 and maybe you want to customize it a bit. But for all the other
177 modules in your dist, $VERSION is really just bookkeeping and all that's
178 important is it goes up every time the module is changed. Doing this
179 by hand is a pain and you often forget.
181 Simplest way to do it automatically is to use your version control
182 system's revision number (you are using version control, right?).
184 In CVS, RCS and SVN you use $Revision$ (see the documentation of your
185 version control system for details). Every time the file is checked
186 in the $Revision$ will be updated, updating your $VERSION.
188 SVN uses a simple integer for $Revision$ so you can adapt it for your
191 ($VERSION) = q$Revision$ =~ /(\d+)/;
193 In CVS and RCS version 1.9 is followed by 1.10. Since CPAN compares
194 version numbers numerically we use a sprintf() to convert 1.9 to 1.009
195 and 1.10 to 1.010 which compare properly.
197 $VERSION = sprintf "%d.%03d", q$Revision$ =~ /(\d+)\.(\d+)/g;
199 If branches are involved (ie. $Revision: 1.5.3.4$) its a little more
202 # must be all on one line or MakeMaker will get confused.
203 $VERSION = do { my @r = (q$Revision$ =~ /\d+/g); sprintf "%d."."%03d" x $#r, @r };
205 In SVN, $Revision$ should be the same for every file in the project so
206 they would all have the same $VERSION. CVS and RCS have a different
207 $Revision$ per file so each file will have a differnt $VERSION.
208 Distributed version control systems, such as SVK, may have a different
209 $Revision$ based on who checks out the file leading to a different $VERSION
210 on each machine! Finally, some distributed version control systems, such
211 as darcs, have no concept of revision number at all.
214 =item What's this F<META.yml> thing and how did it get in my F<MANIFEST>?!
216 F<META.yml> is a module meta-data file pioneered by Module::Build and
217 automatically generated as part of the 'distdir' target (and thus
218 'dist'). See L<ExtUtils::MakeMaker/"Module Meta-Data">.
220 To shut off its generation, pass the C<NO_META> flag to C<WriteMakefile()>.
223 =item How do I delete everything not in my F<MANIFEST>?
225 Some folks are surpried that C<make distclean> does not delete
226 everything not listed in their MANIFEST (thus making a clean
227 distribution) but only tells them what they need to delete. This is
228 done because it is considered too dangerous. While developing your
229 module you might write a new file, not add it to the MANIFEST, then
230 run a C<distclean> and be sad because your new work was deleted.
232 If you really want to do this, you can use
233 C<ExtUtils::Manifest::manifind()> to read the MANIFEST and File::Find
234 to delete the files. But you have to be careful. Here's a script to
235 do that. Use at your own risk. Have fun blowing holes in your foot.
243 use ExtUtils::Manifest qw(maniread);
245 my %manifest = map {( $_ => 1 )}
246 grep { File::Spec->canonpath($_) }
247 keys %{ maniread() };
249 if( !keys %manifest ) {
250 print "No files found in MANIFEST. Stopping.\n";
256 my $path = File::Spec->canonpath($_);
258 return unless -f $path;
259 return if exists $manifest{ $path };
261 print "unlink $path\n";
270 =item Which zip should I use on Windows for '[nd]make zipdist'?
272 We recommend InfoZIP: L<http://www.info-zip.org/Zip.html>
281 =item How to I prevent "object version X.XX does not match bootstrap parameter Y.YY" errors?
283 XS code is very sensitive to the module version number and will
284 complain if the version number in your Perl module doesn't match. If
285 you change your module's version # without rerunning Makefile.PL the old
286 version number will remain in the Makefile causing the XS code to be built
287 with the wrong number.
289 To avoid this, you can force the Makefile to be rebuilt whenever you
290 change the module containing the version number by adding this to your
291 WriteMakefile() arguments.
293 depend => { '$(FIRST_MAKEFILE)' => '$(VERSION_FROM)' }
296 =item How do I make two or more XS files coexist in the same directory?
298 Sometimes you need to have two and more XS files in the same package.
299 One way to go is to put them into separate directories, but sometimes
300 this is not the most suitable solution. The following technique allows
301 you to put two (and more) XS files in the same directory.
303 Let's assume that we have a package C<Cool::Foo>, which includes
304 C<Cool::Foo> and C<Cool::Bar> modules each having a separate XS
305 file. First we use the following I<Makefile.PL>:
307 use ExtUtils::MakeMaker;
311 VERSION_FROM => 'Foo.pm',
312 OBJECT => q/$(O_FILES)/,
313 # ... other attrs ...
316 Notice the C<OBJECT> attribute. MakeMaker generates the following
317 variables in I<Makefile>:
319 # Handy lists of source code files:
327 Therefore we can use the C<O_FILES> variable to tell MakeMaker to use
328 these objects into the shared library.
330 That's pretty much it. Now write I<Foo.pm> and I<Foo.xs>, I<Bar.pm>
331 and I<Bar.xs>, where I<Foo.pm> bootstraps the shared library and
332 I<Bar.pm> simply loading I<Foo.pm>.
334 The only issue left is to how to bootstrap I<Bar.xs>. This is done
337 MODULE = Cool::Foo PACKAGE = Cool::Foo
340 # boot the second XS file
341 boot_Cool__Bar(aTHX_ cv);
343 If you have more than two files, this is the place where you should
344 boot extra XS files from.
346 The following four files sum up all the details discussed so far.
354 our @ISA = qw(DynaLoader);
355 our $VERSION = '0.01';
356 bootstrap Cool::Foo $VERSION;
364 use Cool::Foo; # bootstraps Bar.xs
374 MODULE = Cool::Foo PACKAGE = Cool::Foo
377 # boot the second XS file
378 boot_Cool__Bar(aTHX_ cv);
380 MODULE = Cool::Foo PACKAGE = Cool::Foo PREFIX = cool_foo_
383 cool_foo_perl_rules()
386 fprintf(stderr, "Cool::Foo says: Perl Rules\n");
394 MODULE = Cool::Bar PACKAGE = Cool::Bar PREFIX = cool_bar_
397 cool_bar_perl_rules()
400 fprintf(stderr, "Cool::Bar says: Perl Rules\n");
402 And of course a very basic test:
407 BEGIN { plan tests => 1 };
410 Cool::Foo::perl_rules();
411 Cool::Bar::perl_rules();
414 This tip has been brought to you by Nick Ing-Simmons and Stas Bekman.
420 If you have a question you'd like to see added to the FAQ (whether or
421 not you have the answer) please send it to makemaker@perl.org.
425 The denizens of makemaker@perl.org.
429 L<ExtUtils::MakeMaker>