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Inline(3pm)           User Contributed Perl Documentation          Inline(3pm)



NAME
       Inline - Write Perl subroutines in other programming languages.

SYNOPSIS
           use Inline C;

           print "9 + 16 = ", add(9, 16), "\n";
           print "9 - 16 = ", subtract(9, 16), "\n";

           __END__
           __C__
           int add(int x, int y) {
             return x + y;
           }

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

DESCRIPTION
       The Inline module allows you to put source code from other programming
       languages directly "inline" in a Perl script or module. The code is
       automatically compiled as needed, and then loaded for immediate access
       from Perl.

       Inline saves you from the hassle of having to write and compile your
       own glue code using facilities like XS or SWIG. Simply type the code
       where you want it and run your Perl as normal. All the hairy details
       are handled for you. The compilation and installation of your code
       chunks all happen transparently; all you will notice is the delay of
       compilation on the first run.

       The Inline code only gets compiled the first time you run it (or when-
       ever it is modified) so you only take the performance hit once. Code
       that is Inlined into distributed modules (like on the CPAN) will get
       compiled when the module is installed, so the end user will never
       notice the compilation time.

       Best of all, it works the same on both Unix and Microsoft Windows. See
       Inline-Support for support information.

       Why Inline?

       Do you want to know "Why would I use other languages in Perl?" or "Why
       should I use Inline to do it?"? I'll try to answer both.

       Why would I use other languages in Perl?
           The most obvious reason is performance. For an interpreted lan-
           guage, Perl is very fast. Many people will say "Anything Perl can
           do, C can do faster". (They never mention the development time :-)
           Anyway, you may be able to remove a bottleneck in your Perl code by
           using another language, without having to write the entire program
           in that language. This keeps your overall development time down,
           because you're using Perl for all of the non-critical code.

           Another reason is to access functionality from existing API-s that
           use the language. Some of this code may only be available in binary
           form.  But by creating small subroutines in the native language,
           you can "glue" existing libraries to your Perl. As a user of the
           CPAN, you know that code reuse is a good thing. So why throw away
           those Fortran libraries just yet?

           If you are using Inline with the C language, then you can access
           the full internals of Perl itself. This opens up the floodgates to
           both extreme power and peril.

           Maybe the best reason is "Because you want to!". Diversity keeps
           the world interesting. TMTOWTDI!

       Why should I use Inline to do it?
           There are already two major facilities for extending Perl with C.
           They are XS and SWIG. Both are similar in their capabilities, at
           least as far as Perl is concerned. And both of them are quite dif-
           ficult to learn compared to Inline.

           There is a big fat learning curve involved with setting up and
           using the XS environment. You need to get quite intimate with the
           following docs:

            * perlxs
            * perlxstut
            * perlapi
            * perlguts
            * perlmod
            * h2xs
            * xsubpp
            * ExtUtils::MakeMaker

           With Inline you can be up and running in minutes. There is a C
           Cookbook with lots of short but complete programs that you can
           extend to your real-life problems. No need to learn about the com-
           plicated build process going on in the background. You don't even
           need to compile the code yourself. Inline takes care of every last
           detail except writing the C code.

           Perl programmers cannot be bothered with silly things like compil-
           ing.  "Tweak, Run, Tweak, Run" is our way of life. Inline does all
           the dirty work for you.

           Another advantage of Inline is that you can use it directly in a
           script.  You can even use it in a Perl one-liner. With XS and SWIG,
           you always set up an entirely separate module. Even if you only
           have one or two functions. Inline makes easy things easy, and hard
           things possible. Just like Perl.

           Finally, Inline supports several programming languages (not just C
           and C++). As of this writing, Inline has support for C, C++, Java,
           Python, Ruby, Tcl, Assembler, Basic, Guile, Befunge, Octave, Awk,
           BC, TT (Template Toolkit), WebChat and even PERL. New Inline Lan-
           guage Support Modules (ILSMs) are regularly being added. See
           Inline-API for details on how to create your own ILSM.

Using the Inline.pm Module
       Inline is a little bit different than most of the Perl modules that you
       are used to. It doesn't import any functions into your namespace and it
       doesn't have any object oriented methods. Its entire interface (with
       two minor exceptions) is specified through the 'use Inline ...' com-
       mand.

       This section will explain all of the different ways to "use Inline". If
       you want to begin using C with Inline immediately, see Inline::C-Cook-
       book.

       The Basics

       The most basic form for using Inline is:

           use Inline X => "X source code";

       where 'X' is one of the supported Inline programming languages. The
       second parameter identifies the source code that you want to bind to
       Perl. The source code can be specified using any of the following syn-
       taxes:

       The DATA Keyword.
               use Inline Java => 'DATA';

               # Perl code goes here ...

               __DATA__
               __Java__
               /* Java code goes here ... */

           The easiest and most visually clean way to specify your source code
           in an Inline Perl program is to use the special "DATA" keyword.
           This tells Inline to look for a special marker in your "DATA" file-
           handle's input stream. In this example the special marker is
           "__Java__", which is the programming language surrounded by double
           underscores.

           In case you've forgotten, the "DATA" pseudo file is comprised of
           all the text after the "__END__" or "__DATA__" section of your pro-
           gram. If you're working outside the "main" package, you'd best use
           the "__DATA__" marker or else Inline will not find your code.

           Using this scheme keeps your Perl code at the top, and all the ugly
           Java stuff down below where it belongs. This is visually clean and
           makes for more maintainable code. An excellent side benefit is that
           you don't have to escape any characters like you might in a Perl
           string. The source code is verbatim. For these reasons, I prefer
           this method the most.

           The only problem with this style is that since Perl can't read the
           "DATA" filehandle until runtime, it obviously can't bind your func-
           tions until runtime. The net effect of this is that you can't use
           your Inline functions as barewords (without predeclaring them)
           because Perl has no idea they exist during compile time.

       The FILE and BELOW keywords.
               use Inline::Files;
               use Inline Java => 'FILE';

               # Perl code goes here ...

               __JAVA__
               /* Java code goes here ... */

           This is the newest method of specifying your source code. It makes
           use of the Perl module "Inline::Files" written by Damian Conway.
           The basic style and meaning are the same as for the "DATA" keyword,
           but there are a few syntactic and semantic twists.

           First, you must say 'use Inline::Files' before you 'use Inline'
           code that needs those files. The special '"DATA"' keyword is
           replaced by either '"FILE"' or '"BELOW"'. This allows for the bad
           pun idiom of:

               use Inline C => 'BELOW';

           You can omit the "__DATA__" tag now. Inline::Files is a source fil-
           ter that will remove these sections from your program before Perl
           compiles it. They are then available for Inline to make use of. And
           since this can all be done at compile time, you don't have to worry
           about the caveats of the 'DATA' keyword.

           This module has a couple small gotchas. Since Inline::Files only
           recognizes file markers with capital letters, you must specify the
           capital form of your language name. Also, there is a startup time
           penalty for using a source code filter.

           At this point Inline::Files is alpha software and use of it is
           experimental. Inline's integration of this module is also fledgling
           at the time being. One of things I plan to do with Inline::Files is
           to get line number info so when an extension doesn't compile, the
           error messages will point to the correct source file and line num-
           ber.

           My best advice is to use Inline::Files for testing (especially as
           support for it improves), but use DATA for production and dis-
           tributed/CPAN code.

       Strings
               use Inline Java => <<'END';

               /* Java code goes here ... */
               END

               # Perl code goes here ...

           You also just specify the source code as a single string. A handy
           way to write the string is to use Perl's "here document" style of
           quoting. This is ok for small functions but can get unwieldy in the
           large. On the other hand, the string variant probably has the least
           startup penalty and all functions are bound at compile time.

           If you wish to put the string into a scalar variable, please be
           aware that the "use" statement is a compile time directive. As
           such, all the variables it uses must also be set at compile time,
           "before" the 'use Inline' statement. Here is one way to do it:

               my $code;
               BEGIN {
                   $code = <<END;

               /* Java code goes here ... */
               END
               }
               use Inline Java => $code;

               # Perl code goes here ...

       The bind() Function
           An alternative to using the BEGIN block method is to specify the
           source code at run time using the 'Inline->bind()' method. (This is
           one of the interface exceptions mentioned above) The "bind()"
           method takes the same arguments as 'use Inline ...'.

               my $code = <<END;

               /* Java code goes here ... */
               END

               Inline->bind(Java => $code);

           You can think of "bind()" as a way to "eval()" code in other pro-
           gramming languages.

           Although bind() is a powerful feature, it is not recommended for
           use in Inline based modules. In fact, it won't work at all for
           installable modules. See instructions below for creating modules
           with Inline.

       Other Methods
           The source code for Inline can also be specified as an external
           filename, a reference to a subroutine that returns source code, or
           a reference to an array that contains lines of source code. These
           methods are less frequently used but may be useful in some situa-
           tions.

       Shorthand
           If you are using the 'DATA' or 'FILE' methods described above and
           there are no extra parameters, you can omit the keyword altogether.
           For example:

               use Inline 'Java';

               # Perl code goes here ...

               __DATA__
               __Java__
               /* Java code goes here ... */

           or

               use Inline::Files;
               use Inline 'Java';

               # Perl code goes here ...

               __JAVA__
               /* Java code goes here ... */

       More about the DATA Section

       If you are writing a module, you can also use the DATA section for POD
       and AutoLoader subroutines. Just be sure to put them before the first
       Inline marker. If you install the helper module "Inline::Filters", you
       can even use POD inside your Inline code. You just have to specify a
       filter to strip it out.

       You can also specify multiple Inline sections, possibly in different
       programming languages. Here is another example:

           # The module Foo.pm
           package Foo;
           use AutoLoader;

           use Inline C;
           use Inline C => DATA => FILTERS => 'Strip_POD';
           use Inline Python;

           1;

           __DATA__

           sub marine {
               # This is an autoloaded subroutine
           }

           =head1 External subroutines

           =cut

           __C__
           /* First C section */

           __C__
           /* Second C section */
           =head1 My C Function

           Some POD doc.

           =cut

           __Python__
           """A Python Section"""

       An important thing to remember is that you need to have one "use Inline
       Foo => 'DATA'" for each "__Foo__" marker, and they must be in the same
       order. This allows you to apply different configuration options to each
       section.

       Configuration Options

       Inline trys to do the right thing as often as possible. But sometimes
       you may need to override the default actions. This is easy to do. Sim-
       ply list the Inline configuration options after the regular Inline
       parameters. All congiguration options are specified as (key, value)
       pairs.

           use Inline (C => 'DATA',
                       DIRECTORY => './inline_dir',
                       LIBS => '-lfoo',
                       INC => '-I/foo/include',
                       PREFIX => 'XXX_',
                       WARNINGS => 0,
                      );

       You can also specify the configuration options on a separate Inline
       call like this:

           use Inline (C => Config =>
                       DIRECTORY => './inline_dir',
                       LIBS => '-lfoo',
                       INC => '-I/foo/include',
                       PREFIX => 'XXX_',
                       WARNINGS => 0,
                      );
           use Inline C => <<'END_OF_C_CODE';

       The special keyword 'Config' tells Inline that this is a configuration-
       only call. No source code will be compiled or bound to Perl.

       If you want to specify global configuration options that don't apply to
       a particular language, just leave the language out of the call.  Like
       this:

           use Inline Config => WARNINGS => 0;

       The Config options are inherited and additive. You can use as many Con-
       fig calls as you want. And you can apply different options to different
       code sections. When a source code section is passed in, Inline will
       apply whichever options have been specified up to that point. Here is a
       complex configuration example:

           use Inline (Config =>
                       DIRECTORY => './inline_dir',
                      );
           use Inline (C => Config =>
                       LIBS => '-lglobal',
                      );
           use Inline (C => 'DATA',         # First C Section
                       LIBS => ['-llocal1', '-llocal2'],
                      );
           use Inline (Config =>
                       WARNINGS => 0,
                      );
           use Inline (Python => 'DATA',    # First Python Section
                       LIBS => '-lmypython1',
                      );
           use Inline (C => 'DATA',         # Second C Section
                       LIBS => [undef, '-llocal3'],
                      );

       The first "Config" applies to all subsequent calls. The second "Config"
       applies to all subsequent "C" sections (but not "Python" sections). In
       the first "C" section, the external libraries "global", "local1" and
       "local2" are used. (Most options allow either string or array ref
       forms, and do the right thing.) The "Python" section does not use the
       "global" library, but does use the same "DIRECTORY", and has warnings
       turned off. The second "C" section only uses the "local3" library.
       That's because a value of "undef" resets the additive behavior.

       The "DIRECTORY" and "WARNINGS" options are generic Inline options. All
       other options are language specific. To find out what the "C" options
       do, see "Inline::C".

       On and Off

       If a particular config option has value options of 1 and 0, you can use
       the ENABLE and DISABLE modifiers. In other words, this:

           use Inline Config =>
                      FORCE_BUILD => 1,
                      CLEAN_AFTER_BUILD => 0;

       could be reworded as:

           use Inline Config =>
                      ENABLE => FORCE_BUILD,
                      DISABLE => CLEAN_AFTER_BUILD;

       Playing 'with' Others

       Inline has a special configuration syntax that tells it to get more
       configuration options from other Perl modules. Here is an example:

           use Inline with => 'Event';

       This tells Inline to load the module "Event.pm" and ask it for configu-
       ration information. Since "Event" has a C API of its own, it can pass
       Inline all of the information it needs to be able to use "Event" C
       callbacks seamlessly.

       That means that you don't need to specify the typemaps, shared
       libraries, include files and other information required to get this to
       work.

       You can specify a single module or a list of them. Like:

           use Inline with => qw(Event Foo Bar);

       Currently, "Event" is the only module that works with Inline.

       Inline Shortcuts

       Inline lets you set many configuration options from the command line.
       These options are called 'shortcuts'. They can be very handy,
       especially when you only want to set the options temporarily, for say,
       debugging.

       For instance, to get some general information about your Inline code in
       the script "Foo.pl", use the command:

           perl -MInline=INFO Foo.pl

       If you want to force your code to compile, even if its already done,
       use:

           perl -MInline=FORCE Foo.pl

       If you want to do both, use:

           perl -MInline=INFO -MInline=FORCE Foo.pl

       or better yet:

           perl -MInline=INFO,FORCE Foo.pl

       The Inline DIRECTORY

       Inline needs a place to build your code and to install the results of
       the build. It uses a single directory named '.Inline/' under normal
       circumstances. If you create this directory in your home directory, the
       current directory or in the directory where your program resides,
       Inline will find and use it. You can also specify it in the environment
       variable "PERL_INLINE_DIRECTORY" or directly in your program, by using
       the "DIRECTORY" keyword option. If Inline cannot find the directory in
       any of these places it will create a '_Inline/' directory in either
       your current directory or the directory where your script resides.

       One of the key factors to using Inline successfully, is understanding
       this directory. When developing code it is usually best to create this
       directory (or let Inline do it) in your current directory. Remember
       that there is nothing sacred about this directory except that it holds
       your compiled code. Feel free to delete it at any time. Inline will
       simply start from scratch and recompile your code on the next run. If
       you have several programs that you want to force to recompile, just
       delete your '.Inline/' directory.

       It is probably best to have a separate '.Inline/' directory for each
       project that you are working on. You may want to keep stable code in
       the <.Inline/> in your home directory. On multi-user systems, each user
       should have their own '.Inline/' directories. It could be a security
       risk to put the directory in a shared place like "/tmp/".

       Debugging Inline Errors

       All programmers make mistakes. When you make a mistake with Inline,
       like writing bad C code, you'll get a big error report on your screen.
       This report tells you where to look to do the debugging. Some languages
       may also dump out the error messages generated from the build.

       When Inline needs to build something it creates a subdirectory under
       your "DIRECTORY/build/" directory. This is where it writes all the com-
       ponents it needs to build your extension. Things like XS files, Make-
       files and output log files.

       If everything goes OK, Inline will delete this subdirectory. If there
       is an error, Inline will leave the directory intact and print its loca-
       tion.  The idea is that you are supposed to go into that directory and
       figure out what happened.

       Read the doc for your particular Inline Language Support Module for
       more information.

       The 'config' Registry File

       Inline keeps a cached file of all of the Inline Language Support Mod-
       ule's meta data in a file called "config". This file can be found in
       your "DIRECTORY" directory. If the file does not exist, Inline creates
       a new one. It will search your system for any module beginning with
       "Inline::". It will then call that module's "register()" method to get
       useful information for future invocations.

       Whenever you add a new ILSM, you should delete this file so that Inline
       will auto-discover your newly installed language module.

Configuration Options
       This section lists all of the generic Inline configuration options. For
       language specific configuration, see the doc for that language.

       DIRECTORY

       The "DIRECTORY" config option is the directory that Inline uses to both
       build and install an extension.

       Normally Inline will search in a bunch of known places for a directory
       called '.Inline/'. Failing that, it will create a directory called
       '_Inline/'

       If you want to specify your own directory, use this configuration
       option.

       Note that you must create the "DIRECTORY" directory yourself. Inline
       will not do it for you.

       NAME

       You can use this option to set the name of your Inline extension object
       module. For example:

           use Inline C => 'DATA',
                      NAME => 'Foo::Bar';

       would cause your C code to be compiled in to the object:

           lib/auto/Foo/Bar/Bar.so
           lib/auto/Foo/Bar/Bar.inl

       (The .inl component contains dependency information to make sure the
       source code is in sync with the executable)

       If you don't use NAME, Inline will pick a name for you based on your
       program name or package name. In this case, Inline will also enable the
       AUTONAME option which mangles in a small piece of the MD5 fingerprint
       into your object name, to make it unique.

       AUTONAME

       This option is enabled whenever the NAME parameter is not specified. To
       disable it say:

           use Inline C => 'DATA',
                      DISABLE => 'AUTONAME';

       AUTONAME mangles in enough of the MD5 fingerprint to make your module
       name unique. Objects created with AUTONAME will never get replaced.
       That also means they will never get cleaned up automatically.

       AUTONAME is very useful for small throw away scripts. For more serious
       things, always use the NAME option.

       VERSION

       Specifies the version number of the Inline extension object. It is used
       only for modules, and it must match the global variable $VERSION.
       Additionally, this option should used if (and only if) a module is
       being set up to be installed permanently into the Perl sitelib tree.
       Inline will croak if you use it otherwise.

       The presence of the VERSION parameter is the official way to let Inline
       know that your code is an installable/installed module. Inline will
       never generate an object in the temporary cache (_Inline/ directory) if
       VERSION is set. It will also never try to recompile a module that was
       installed into someone's Perl site tree.

       So the basic rule is develop without VERSION, and deliver with VERSION.

       WITH

       "WITH" can also be used as a configuration option instead of using the
       special 'with' syntax. Do this if you want to use different sections of
       Inline code with different modules. (Probably a very rare usage)

           use Event;
           use Inline C => DATA => WITH => 'Event';

       Modules specified using the config form of "WITH" will not be automati-
       cally required. You must "use" them yourself.

       GLOBAL_LOAD

       This option is for compiled languages only. It tells Inline to tell
       DynaLoader to load an object file in such a way that its symbols can be
       dynamically resolved by other object files. May not work on all plat-
       forms. See the "GLOBAL" shortcut below.

       UNTAINT

       You must use this option whenever you use Perl's "-T" switch, for taint
       checking. This option tells Inline to blindly untaint all tainted vari-
       ables. It also turns on SAFEMODE by default. See the "UNTAINT" shortcut
       below.

       SAFEMODE

       Perform extra safety checking, in an attempt to thwart malicious code.
       This option cannot guarantee security, but it does turn on all the cur-
       rently implemented checks.

       There is a slight startup penalty by using SAFEMODE. Also, using
       UNTAINT automatically turns this option on. If you need your code to
       start faster under "-T" (taint) checking, you'll need to turn this
       option off manually. Only do this if you are not worried about security
       risks. See the "UNSAFE" shortcut below.

       FORCE_BUILD

       Makes Inline build (compile) the source code every time the program is
       run. The default is 0. See the "FORCE" shortcut below.

       BUILD_NOISY

       Tells ILSMs that they should dump build messages to the terminal rather
       than be silent about all the build details.

       BUILD_TIMERS

       Tells ILSMs to print timing information about how long each build phase
       took. Usually requires "Time::HiRes".

       CLEAN_AFTER_BUILD

       Tells Inline to clean up the current build area if the build was suc-
       cessful. Sometimes you want to DISABLE this for debugging. Default is
       1. See the "NOCLEAN" shortcut below.

       CLEAN_BUILD_AREA

       Tells Inline to clean up the old build areas within the entire Inline
       DIRECTORY. Default is 0. See the "CLEAN" shortcut below.

       PRINT_INFO

       Tells Inline to print various information about the source code.
       Default is 0. See the "INFO" shortcut below.

       PRINT_VERSION

       Tells Inline to print Version info about itself. Default is 0. See the
       "VERSION" shortcut below.

       REPORTBUG

       Puts Inline into 'REPORTBUG' mode, which is what you want if you desire
       to report a bug.

       WARNINGS

       This option tells Inline whether to print certain warnings. Default is
       1.

Inline Configuration Shortcuts
       This is a list of all the shorcut configuration options currently
       available for Inline. Specify them from the command line when running
       Inline scripts.

           perl -MInline=NOCLEAN inline_script.pl

       or

           perl -MInline=Info,force,NoClean inline_script.pl

       You can specify multiple shortcuts separated by commas. They are not
       case sensitive. You can also specify shorcuts inside the Inline program
       like this:

           use Inline 'Info', 'Force', 'Noclean';

       NOTE: If a 'use Inline' statement is used to set shortcuts, it can not
       be used for additional purposes.

       CLEAN
           Tells Inline to remove any build directories that may be lying
           around in your build area. Normally these directories get removed
           immediately after a successful build. Exceptions are when the build
           fails, or when you use the NOCLEAN or REPORTBUG options.

       FORCE
           Forces the code to be recompiled, even if everything is up to date.

       GLOBAL
           Turns on the GLOBAL_LOAD option.

       INFO
           This is a very useful option when you want to know what's going on
           under the hood. It tells Inline to print helpful information to
           "STDERR".  Among the things that get printed is a list of which
           Inline functions were successfully bound to Perl.

       NOCLEAN
           Tells Inline to leave the build files after compiling.

       NOISY
           Use the BUILD_NOISY option to print messages during a build.

       REPORTBUG
           Puts Inline into 'REPORTBUG' mode, which does special processing
           when you want to report a bug. REPORTBUG also automatically forces
           a build, and doesn't clean up afterwards. This is so that you can
           tar and mail the build directory to me. REPORTBUG will print exact
           instructions on what to do. Please read and follow them carefully.

           NOTE: REPORTBUG informs you to use the tar command. If your system
           does not have tar, please use the equivalent "zip" command.

       SAFE
           Turns SAFEMODE on. UNTAINT will turn this on automatically. While
           this mode performs extra security checking, it does not guarantee
           safety.

       SITE_INSTALL
           This parameter used to be used for creating installable Inline mod-
           ules.  It has been removed from Inline altogether and replaced with
           a much simpler and more powerful mechanism, "Inline::MakeMaker".
           See the section below on how to create modules with Inline.

       TIMERS
           Turn on BUILD_TIMERS to get extra diagnostic info about builds.

       UNSAFE
           Turns SAFEMODE off. Use this in combination with UNTAINT for
           slightly faster startup time under "-T". Only use this if you are
           sure the environment is safe.

       UNTAINT
           Turn the UNTAINT option on. Used with "-T" switch.

       VERSION
           Tells Inline to report its release version.

Writing Modules with Inline
       Writing CPAN modules that use C code is easy with Inline. Let's say
       that you wanted to write a module called "Math::Simple". Start by using
       the following command:

           h2xs -PAXn Math::Simple

       This will generate a bunch of files that form a skeleton of what you
       need for a distributable module. (Read the h2xs manpage to find out
       what the options do) Next, modify the "Simple.pm" file to look like
       this:

           package Math::Simple;
           $VERSION = '1.23';

           use base 'Exporter';
           @EXPORT_OK = qw(add subtract);
           use strict;

           use Inline C => 'DATA',
                      VERSION => '1.23',
                      NAME => 'Math::Simple';

           1;

           __DATA__

           =pod

           =cut

           __C__
           int add(int x, int y) {
             return x + y;
           }

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

       The important things to note here are that you must specify a "NAME"
       and "VERSION" parameter. The "NAME" must match your module's package
       name. The "VERSION" parameter must match your module's $VERSION vari-
       able and they must be of the form "/^\d\.\d\d$/".

       NOTE: These are Inline's sanity checks to make sure you know what
       you're doing before uploading your code to CPAN. They insure that once
       the module has been installed on someone's system, the module would not
       get automatically recompiled for any reason. This makes Inline based
       modules work in exactly the same manner as XS based ones.

       Finally, you need to modify the Makefile.PL. Simply change:

           use ExtUtils::MakeMaker;

       to

           use Inline::MakeMaker;

       When the person installing "Math::Simple" does a ""make"", the gener-
       ated Makefile will invoke Inline in such a way that the C code will be
       compiled and the executable code will be placed into the "./blib"
       directory. Then when a ""make install"" is done, the module will be
       copied into the appropiate Perl sitelib directory (which is where an
       installed module should go).

       Now all you need to do is:

           perl Makefile.PL
           make dist

       That will generate the file "Math-Simple-0.20.tar.gz" which is a dis-
       tributable package. That's all there is to it.

       IMPORTANT NOTE: Although the above steps will produce a workable mod-
       ule, you still have a few more responsibilities as a budding new CPAN
       author. You need to write lots of documentation and write lots of
       tests. Take a look at some of the better CPAN modules for ideas on cre-
       ating a killer test harness.  Actually, don't listen to me, go read
       these:

           perldoc perlnewmod
           http://www.cpan.org/modules/04pause.html
           http://www.cpan.org/modules/00modlist.long.html

How Inline Works
       In reality, Inline just automates everything you would need to do if
       you were going to do it by hand (using XS, etc).

       Inline performs the following steps:

       1) Receive the Source Code
           Inline gets the source code from your script or module with a
           statements like the following:

               use Inline C => "Source-Code";

           or

               use Inline;
               bind Inline C => "Source-Code";

           where "C" is the programming language of the source code, and
           "Source-Code" is a string, a file name, an array reference, or the
           special 'DATA' keyword.

           Since Inline is coded in a ""use"" statement, everything is done
           during Perl's compile time. If anything needs to be done that will
           affect the "Source-Code", it needs to be done in a "BEGIN" block
           that is before the ""use Inline ..."" statement. If you really need
           to specify code to Inline at runtime, you can use the "bind()"
           method.

           Source code that is stowed in the 'DATA' section of your code, is
           read in by an "INIT" subroutine in Inline. That's because the
           "DATA" filehandle is not available at compile time.

       2) Check if the Source Code has been Built
           Inline only needs to build the source code if it has not yet been
           built.  It accomplishes this seemingly magical task in an extremely
           simple and straightforward manner. It runs the source text through
           the "Digest::MD5" module to produce a 128-bit "fingerprint" which
           is virtually unique. The fingerprint along with a bunch of other
           contingency information is stored in a ".inl" file that sits next
           to your executable object. For instance, the "C" code from a script
           called "example.pl" might create these files:

               example_pl_3a9a.so
               example_pl_3a9a.inl

           If all the contingency information matches the values stored in the
           ".inl" file, then proceed to step 8. (No compilation is necessary)

       3) Find a Place to Build and Install
           At this point Inline knows it needs to build the source code. The
           first thing to figure out is where to create the great big mess
           associated with compilation, and where to put the object when it's
           done.

           By default Inline will try to build and install under the first
           place that meets one of the following conditions:

               A) The DIRECTORY= config option; if specified
               B) The PERL_INLINE_DIRECTORY environment variable; if set
               C) .Inline/ (in current directory); if exists and $PWD != $HOME
               D) bin/.Inline/ (in directory of your script); if exists
               E) ~/.Inline/; if exists
               F) ./_Inline/; if exists
               G) bin/_Inline; if exists
               H) Create ./_Inline/; if possible
               I) Create bin/_Inline/; if possible

           Failing that, Inline will croak. This is rare and easily remedied
           by just making a directory that Inline will use;

           If the module option is being compiled for permanent installation,
           then Inline will only use "./_Inline/" to build in, and the $Con-
           fig{installsitearch} directory to install the executable in. This
           action is caused by Inline::MakeMaker, and is intended to be used
           in modules that are to be distributed on the CPAN, so that they get
           installed in the proper place.

       4) Parse the Source for Semantic Cues
           Inline::C uses the module "Parse::RecDescent" to parse through your
           chunks of C source code and look for things that it can create run-
           time bindings to. In "C" it looks for all of the function defini-
           tions and breaks them down into names and data types. These ele-
           ments are used to correctly bind the "C" function to a "Perl" sub-
           routine. Other Inline languages like Python and Java actually use
           the "python" and "javac" modules to parse the Inline code.

       5) Create the Build Environment
           Now Inline can take all of the gathered information and create an
           environment to build your source code into an executable. Without
           going into all the details, it just creates the appropriate direc-
           tories, creates the appropriate source files including an XS file
           (for C) and a "Makefile.PL".

       6) Build the Code and Install the Executable
           The planets are in alignment. Now for the easy part. Inline just
           does what you would do to install a module. ""perl Makefile.PL &&
           make && make test && make install"". If something goes awry, Inline
           will croak with a message indicating where to look for more info.

       7) Tidy Up
           By default, Inline will remove all of the mess created by the build
           process, assuming that everything worked. If the build fails,
           Inline will leave everything intact, so that you can debug your
           errors. Setting the "NOCLEAN" shortcut option will also stop Inline
           from cleaning up.

       8) DynaLoad the Executable
           For C (and C++), Inline uses the "DynaLoader::bootstrap" method to
           pull your external module into "Perl" space. Now you can call all
           of your external functions like Perl subroutines.

           Other languages like Python and Java, provide their own loaders.

SEE ALSO
       For information about using Inline with C see Inline::C.

       For sample programs using Inline with C see Inline::C-Cookbook.

       For "Formerly Answered Questions" about Inline, see Inline-FAQ.

       For information on supported languages and platforms see Inline-Sup-
       port.

       For information on writing your own Inline Language Support Module, see
       Inline-API.

       Inline's mailing list is inline AT perl.org

       To subscribe, send email to inline-subscribe AT perl.org

BUGS AND DEFICIENCIES
       When reporting a bug, please do the following:

        - Put "use Inline REPORTBUG;" at the top of your code, or
          use the command line option "perl -MInline=REPORTBUG ...".
        - Run your code.
        - Follow the printed directions.

AUTHOR
       Brian Ingerson <INGY AT cpan.org>

       Neil Watkiss <NEILW AT cpan.org> is the author of "Inline::CPP",
       "Inline::Python", "Inline::Ruby", "Inline::ASM", "Inline::Struct" and
       "Inline::Filters". He is known in the innermost Inline circles as the
       "Boy Wonder".

COPYRIGHT
       Copyright (c) 2000, 2001, 2002. Brian Ingerson. All rights reserved.

       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



perl v5.8.8                       2002-10-28                       Inline(3pm)
 

©2005 Comrite