FAQ(1)

NAME
ExtUtils::MakeMaker::FAQ - Frequently Asked Questions About MakeMaker

SYNOPSIS

DESCRIPTION
Document tips and tricks for "ExtUtils::MakeMaker".

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:

      test.pl:
      --------
      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@perl.org.

AUTHOR
The denizens of makemaker@perl.org.

SEE ALSO
ExtUtils::MakeMaker