=head1 NAME

Inline-FAQ - The Inline FAQ

=head1 DESCRIPTION

Welcome to the official Inline FAQ. In this case, B<FAQ> means:

    Formerly Answered Questions

This is a collection of old, long-winded emails that myself and others
have sent to the Inline mailing list. (inline@perl.org) They have been
reviewed and edited for general Inline edification. Some of them may be
related to a specific language. They are presented here in a traditional
FAQ layout.

=head1 General Inline

Since there is only a handful of content so far, all FAQs are currently
under this heading.

=head2 How disposable is a .Inline or _Inline directory?

I probably need to be more emphatic about the roll of _Inline/ cache
directories. Since they are created automatically, they are completely
disposable. I delete them all the time. And it is fine to have a
different one for each project. In fact as long as you don't have
~/.Inline/ defined, Inline will create a new ./_Inline directory (unless,
you've done something to override this automatic process - such as
using the DIRECTORY config option, or using the PERL_INLINE_DIRECTORY
environment variable). You can move that to ./.Inline and it will continue
to work if you want togive it more longevity and hide it from view. There
is a long complicated list of rules about how [_.]Inline/ directories are
used/created. But it was designed to give you the most
flexibility/ease-of-use. Never be afraid to nuke 'em. They'll just pop
right back next time they're needed. :)

=head2 Whatever happened to the SITE_INSTALL option?

SITE_INSTALL is gone. I was going to leave it in and change the
semantics, but thought it better to remove it, so people wouldn't try to
use it the old way. There is now _INSTALL_ (but you're not supposed to
know that :). It works magically through the use of Inline::MakeMaker. I
explained this earlier but it's worth going through again because it's
the biggest change for 0.40. Here's how to 'permanently' install an
Inline extension (Inline based module) with 0.40:

    1) Create a module with Inline.
    2) Test it using the normal/local _Inline/ cache.
    3) Create a Makefile.PL (like the one produced by h2xs)
    4) Change 'use ExtUtils::MakeMaker' to 'use Inline::MakeMaker'
    5) In the Makefile.PL's WriteMakefile() insert:

        CONFIGURE_REQUIRES  =>  {
            'Inline::MakeMaker'     => 0.45,
            'ExtUtils::MakeMaker'   => 6.52,
        },

       (See the "Writing Modules with Inline" section of Inline.pod for
        an explanation/elaboration.)

    6) Change your 'use Inline C => DATA' to 'use Inline C => DATA => NAME
       => Foo => VERSION => 1.23'
    7) Make sure NAME matches your package name ('Foo'), or begins with
       'Foo::'.
    8) If you want to quiet a harmless warning that will appear when the
       module is loaded via "require", do "Inline->init();".
       See "Writing Modules with Inline" in the Inline pod for details.
    9) Make sure VERSION matches $Foo::VERSION. This must be a string (not a
       number) matching /^\d\.\d\d$/
    10) Do the perl/make/test/install dance (thanks binkley :)

With Inline 0.41 (or thereabouts) you can skip steps 3 & 4, and just
say 'perl -MInline=INSTALL ./Foo.pm'. This will work for non-Inline
modules too. It will become the defacto standard (since there is no easy
standard) way of installing a Perl module. It will allow Makefile.PL
parameters 'perl -MInline=INSTALL ./Foo.pm - PREFIX=/home/ingy/perl' and
things like that. It will also make use of a MANIFEST if you provide
one.

=head2 How do I create a binary distribution using Inline?

I've figured out how to create and install a PPM binary distribution;
with or without distributing the C code! And I've decided to share it
with all of you :)

NOTE: Future versions of Inline will make this process a one line
command. But for now just use this simple recipe.

---

The Inline 0.40 distribution comes with a sample extension module called
Math::Simple. Theoretically you could distribute this module on CPAN. It
has all the necessary support for installation. You can find it in
Inline-0.40/modules/Math/Simple/. Here are the steps for converting this
into a binary distribution *without* C source code.

NOTE: The recipient of this binary distribution will need to have the
PPM.pm module installed. This module requires a lot of other CPAN
modules. ActivePerl (available for Win32, Linux, and Solaris) has all of
these bundled. While ActivePerl isn't required, it makes things (a
lot) easier.

1) cd Inline-0.40/Math/Simple/

2) Divide Simple.pm into two files:

    ---8<--- (Simple.pm)
    package Math::Simple;
    use strict;
    require Exporter;
    @Math::Simple::ISA = qw(Exporter);
    @Math::Simple::EXPORT = qw(add subtract);
    $Math::Simple::VERSION = '1.23';

    use Inline (C => 'src/Simple.c' =>
                NAME => 'Math::Simple',
                VERSION => '1.23',
               );
    1;
    ---8<---
    ---8<--- (src/Simple.c)
    int add (int x, int y) {
        return x + y;
    }

    int subtract (int x, int y) {
        return x - y;
    }
    ---8<---

So now you have the Perl in one file and the C in the other. The C code
must be in a subdirectory.

3)
Note that I also changed the term 'DATA' to the name of the C file. This
will work just as if the C were still inline.

4) Run 'perl Makefile.PL'

5) Run 'make test'

6) Get the MD5 key from 'blib/arch/auto/Math/Simple/Simple.inl'

7)
Edit 'blib/lib/Math/Simple.pm'. Change 'src/Simple.c' to
'02c61710cab5b659efc343a9a830aa73' (the MD5 key)

8) Run 'make ppd'

9)
Edit 'Math-Simple.ppd'. Fill in AUTHOR and ABSTRACT if you wish. Then
change:

    <CODEBASE HREF="" />

to

    <CODEBASE HREF="Math-Simple.tar.gz" />

10) Run:

    tar cvf Math-Simple.tar blib
    gzip --best Math-Simple.tar

11)
Run:

    tar cvf Math-Simple-1.23.tar Math-Simple.ppd Math-Simple.tar.gz
    gzip --best Math-Simple-1.23.tar

12) Distribute Math-Simple-1.23.tar.gz with the following instructions:

A) Run:

    gzip -d Math-Simple-1.23.tar.gz
    tar xvzf Math-Simple-1.23.tar

B) Run 'ppm install Math-Simple.ppd'

C) Delete Math-Simple.tar and Math-Simple.ppd.

D) Test with:

    perl -MMath::Simple -le 'print add(37, 42)'

---

That's it. The process should also work with zip instead of tar, but I
haven't tried it.

The recipient of the binary must have Perl built with a matching
architecture. Luckily, ppm will catch this.

For a binary dist *with* C source code, simply omit steps 2, 3, 6, and
7.

If this seems too hard, then in a future version you should be able to
just type:

    make ppm

=head2 Why does C/t/09parser.t fail on Cygwin ?

It doesn't always fail on Cygwin, but if you find that it produces
"unable to remap .... to same address as parent" errors during the
build phase, then it's time for you to run rebaseall.

See http://cygwin.com/faq/faq-nochunks.html#faq.using.fixing-fork-failures
and, if needed, seek further help from the Cygwin mailing list.


=cut
