Added Corran Webster's explanation of how to write extensions in MPW and a pointer to his W documentation.
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+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN">
+<HTML>
+
+<HEAD>
+
+<TITLE>HOWTO: Compiling Python Modules with MPW</TITLE>
+
+</HEAD>
+
+<BODY>
+
+<H1>HOWTO: Compiling Python Modules with MPW</H1>
+
+<blockquote>
+This HOWTO is a slightly reformatted version of an original by
+<A HREF="mailto:cwebster@nevada.edu">Corran Webster</A>, whose
+<A HREF="http://www.nevada.edu/~cwebster/Python/">Python page</A>
+may contain a more up-to-date version.
+</blockquote>
+<HR>
+
+<P>
+The <A HREF="http://www.cwi.nl/~jack/macpython.html">Macintosh version</A>
+of the <A HREF="http://www.python.org/">Python programming language</A> is
+usually compiled with <A HREF="http://www.metrowerks.com/">Metrowerks
+CodeWarrior</A>. As a result, C extension modules are also usually
+compiled with CodeWarrior, and the documentation and sample code reflects
+this. CodeWarrior is a commercial product, and may be beyond the budgets
+of hobbyist hackers, making them dependent on others to compile C extension
+modules. At the present time, many standard C extension modules compile
+"out of the box" on the Macintosh, but in only a few cases is the plugin
+for the Macintosh included in the distribution.
+</P>
+
+<P>
+The <A HREF="http://developer.apple.com/tools/mpw-tools/">Macintosh
+Programmer's Workshop</A> (MPW) is Apple's development environment, and is
+freely available for <A
+HREF="ftp://ftp.apple.com/developer/Tool_Chest/Core_Mac_OS_Tools/MPW_etc./">download</A>
+from Apple, as well as on their Developer CDs. Since Python was originally
+developed using MPW, before CodeWarrior became the dominant MacOS
+development environment, most of the idiosyncrasies of MPW are already
+supported, and compilation of C extension modules in MPW is possible.
+</P>
+
+<P>
+This HOWTO only deals with compiling for PowerPC Macintoshes. The process
+should be similar for 68k Macintoshes using the code fragment manager, but
+I have not attempted this - my old Mac is running NetBSD.
+</P>
+
+<P>
+This way of compiling modules is still experimental. Please read the
+caveats section below.
+</P>
+
+<H2><A NAME="setup">Setting Up MPW for Compiling Python Modules</A></H2>
+
+<P>
+This assumes that you have successfully installed both MPW and Python with
+the Developer's Kit on your Macintosh.
+</P>
+
+<P>
+The first step is to let MPW know where you keep Python. This step is not
+strictly necessary, but will make development easier and improve
+portability. Create a new file in the <CODE>Startup Items</CODE> folder of
+MPW called <A HREF="Python"><CODE>Python</CODE></A>. Type the lines:
+</P>
+
+<PRE>
+set Python "Macintosh HD:Applications:Python 1.5.2c1:"
+set PythonIncludes "{Python}Include"
+set PythonMacIncludes "{Python}Mac:Include"
+set PythonCore "{Python}PythonCore"
+
+export Python PythonIncludes PythonMacIncludes PythonCore
+</PRE>
+
+<P>
+where <CODE>Macintosh HD:Applications:Python 1.5.2c1:</CODE> is replaced by
+the path to the directory where you keep your copy of Python, and the other
+variables reflect where you keep your header files and Python core files.
+The locations here are the standard for Python 1.5.2c1, but they are
+different for Python 1.52b2 and earlier (most notably, the PythonCore is
+kept in the Extensions folder).
+</P>
+
+<P>
+Next, you need to update the <A HREF="config.h"><CODE>config.h</CODE></A>
+file for the <CODE>MrC</CODE> compiler included with MPW. This header file
+is located in the <CODE>:Mac:Include</CODE> folder in the standard
+distribution. You can update it by hand, by adding the lines:
+</P>
+
+<PRE>
+#ifdef __MRC__
+#define BAD_STATIC_FORWARD
+#endif
+</PRE>
+
+<P>
+at the after the similar defines for <CODE>__MWERKS__</CODE> and
+<CODE>__SC__</CODE> in the file. This step is critical: many modules,
+including ones in the standard distribution, will not compile properly
+without this modification (see common problems below).
+</P>
+
+<P>
+Copies of both the <A HREF="Python"><CODE>Python</CODE></A> startup item
+for MPW and the <A HREF="config.h"><CODE>config.h</CODE></A> are included
+here for your convenience.
+</P>
+
+<P>
+If you are porting Unix modules to the mac, you may find it useful to
+install <A
+HREF="http://www.iis.ee.ethz.ch/~neeri/macintosh/gusi-qa.html">GUSI</A> for
+your copy of MPW. GUSI provides some amount of POSIX compatibility, and is
+used by Python itself for this purpose - at the very least having it's
+header files available may be useful. Also of note for people porting Unix
+modules, the most recent alpha version (4.1a8) of <CODE>MrC</CODE> and
+<CODE>MrCpp</CODE> at this writing permits using unix-style pathnames for
+includes via the <CODE>-includes unix</CODE> command line option. I have
+not experimented heavily with this, but will be doing so in the future and
+report my findings.
+</P>
+
+<P>
+You now have MPW and Python set up to allow compilation of modules.
+</P>
+
+<H2><A NAME="compiling">Compiling a Module</A></H2>
+
+<P>
+This assumes that you have a C extension module ready to compile. For
+instructions on how to write a module, see the Python documentation.
+</P>
+
+<P>
+There are three approaches you can take to compiling in MPW: using the
+command line interface, using the MPW <CODE>CreateMake</CODE> command
+(available as the "Create build commands..." menu item, and writing a
+Makefile by hand.
+</P>
+
+<P>
+Before you start any of these, you'll need to know:
+</P>
+
+<UL>
+ <LI>The names and locations of the C source files. In the examples, this
+ is the file <A HREF="xxmodule.c"><CODE>xxmodule.c</CODE></A>, and is in
+ MPW's current working directory.
+ <LI>The name that Python expects to import your module under. In the
+ examples, this is <CODE>xx</CODE>, so the shared library file will be
+ called <CODE>xx.ppc.slb</CODE>.
+ <LI>The location of any additional header files use by the C source. The
+ example does not use any additional header files.
+ <LI>The location of any additional shared libraries which the module needs
+ to link to. The example does not link to any other shared libraries.
+ <LI>The name of the entry point to your module. This is usually the last
+ function in the main C source file, and the name usually starts with
+ <CODE>init</CODE>. In the examples, this is <CODE>initxx</CODE>.
+</UL>
+
+<H3>Using the Command Line</H3>
+
+<P>
+For simple modules consisting of one or two C files, it's often convenient
+to simply use commands in a MPW Worksheet. Usually you will want to set
+MPW's working directory to the directory containing the C source code. The
+following commands compile and link the standard Python test module <A
+HREF="xxmodule.c"><CODE>xxmodule.c</CODE></A>:
+</P>
+
+<PRE>
+MrC "xxmodule.c" -o "xx.c.x" -w off -d HAVE_CONFIG_H ∂
+ -i "{PythonMacIncludes}" ∂
+ -i "{PythonIncludes}"
+PPCLink ∂
+ -o "xx.ppc.slb" ∂
+ "xx.c.x" ∂
+ -t 'shlb' ∂
+ -c 'Pyth' ∂
+ -xm s ∂
+ -d ∂
+ "{PythonCore}" ∂
+ "{SharedLibraries}InterfaceLib" ∂
+ "{SharedLibraries}MathLib" ∂
+ "{SharedLibraries}StdCLib" ∂
+ "{PPCLibraries}StdCRuntime.o" ∂
+ "{PPCLibraries}PPCCRuntime.o" ∂
+ "{PPCLibraries}PPCToolLibs.o" ∂
+ -export initxx
+</PRE>
+
+<P>
+(Note: The last character on each line should appear as "partial
+derivative" symbol, which you type as <KBD>option-d</KBD> and which is
+MPW's line continuation symbol.)
+</P>
+
+<P>
+Any additional header files should be specified by adding their directories
+as extra <CODE>-i</CODE> options to the <CODE>MrC</CODE> command. Any
+additional shared libraries should be added before the PythonCore library
+in the <CODE>PPCLink</CODE> command.
+</P>
+
+<P>
+If there is more than one source file, you will need to duplicate the
+compile command for each source file, and you will need to include all the
+object files in the place where <CODE>"xx.c.x"</CODE> appears in the
+<CODE>PPCLink</CODE> command.
+</P>
+
+<H3>Using CreateMake</H3>
+
+<P>
+For more complex modules, or modules that you are writing yourself, you
+will probably want to use a makefile. Unfortunately MPW's makefiles are
+incompatible with the standard Unix makefiles, so you will not be able to
+use any makefiles which come with a C module.
+</P>
+
+<P>
+Usually, you will want the makefile to reside in the same directory as the
+C source code, so you should set MPW's working directory to that directory
+before proceeding.
+</P>
+
+<P>
+To create a makefile for the standard Python test module <A
+HREF="xxmodule.c"><CODE>xxmodule.c</CODE></A>:
+</P>
+
+<UL>
+ <LI>Select "Create build commands..." from the "Build" Menu.
+ <LI>Type <KBD>xx.ppc.slb</KBD> for the Program Name.
+ <LI>Select "Shared Library" for the Program Type.
+ <LI>Select "PowerPC Only" for the Target.
+ <LI>Click on the "Source Files..." button, and add your module's C source
+ files to the list.
+ <LI>Click on the "Other Options..." button and change the creator type to
+ "Pyth". If you are using additional header files, you can also add their
+ directories at this stage. Click on "Continue" once you have done this.
+ <LI>Click on the "Exported Symbols..." button and type <KBD>initxx</KBD>
+ into the entry field. Click on "Continue" once you have done this.
+ <LI>At this stage, your CreateMake window should look like this: <IMG
+ SRC="html.icons/createmake.png" ALT="[picture of commando window for CreateMake]">
+ <LI>Click on the "CreateMake" button.
+</UL>
+
+<P>
+You will now need to edit the makefile that was just created. Open the
+file "xx.ppc.slb.make" in the current directory and make the following
+changes:
+</P>
+
+<UL>
+ <LI>Change the line
+
+ <PRE>
+Includes =
+</PRE>
+
+ <P>
+ to read
+ </P>
+
+ <PRE>
+Includes = -i "{PythonIncludes}" -i "{PythonMacIncludes}"
+</PRE>
+
+ <P>
+ If you have any additional headers than need to be included, you can add
+ them here as well.
+ <LI>Change the line
+
+ <PRE>
+PPCCOptions = {Includes} {Sym•PPC}
+</PRE>
+
+ <P>
+ to read
+ </P>
+
+ <PRE>
+PPCCOptions = -w off -d HAVE_CONFIG_H {Includes} {Sym•PPC}
+</PRE>
+
+ <P>
+ <LI>After the line
+
+ <PRE>
+ -xm s ∂
+</PRE>
+
+ <P>
+ add
+ </P>
+
+ <PRE>
+ -d ∂
+ "{PythonCore}" ∂
+</PRE>
+
+ <P>
+ If you have any other shared libraries you need to link to, add each on a
+ line before PythonCore, terminating each line with a <CODE>∂</CODE>.
+ </P>
+
+</UL>
+
+<P>Save the file. You are now ready to build.
+</P>
+
+<P>
+Go to the "Build" or "Full Build" menu items, type in
+<KBD>xx.ppc.slb</KBD>, and MPW should take things from there. Any time you
+need to rebuild the shared library, you can simply do another "Build" or
+"Full Build".
+</P>
+
+<H3>Writing a Makefile by Hand</H3>
+
+<P>
+For modules which have complex interdependencies between files, you will
+likely need a more sophisticated makefile than the one created by
+<CODE>CreateMake</CODE>. You will need to be familiar with the MPW
+makefile format, but you can get a start by either using
+<CODE>CreateMake</CODE> to get a simple starting point, or taking another
+MPW makefile as a starting point.
+</P>
+
+<P>
+It is beyond the scope of this HOWTO to go into the generalities of MPW
+makefiles. Documentation on MPW's <CODE>Make</CODE> command can be found
+with the MPW distribution, in particular the documents <A
+HREF="http://developer.apple.com/tools/mpw-tools/books.html#Building">Building
+and Maintaining Programs with MPW (2nd Edition)</A> and the <A
+HREF="http://developer.apple.com/tools/mpw-tools/books.html#CommandRef">MPW
+Command Reference</A>.
+</P>
+
+<P>
+There are a couple of important points to keep in mind when writing a
+makefile by hand:</P>
+
+<UL>
+ <LI>When there are multiple symbols with the same name in object files or
+ shared libraries, <CODE>PPCLink</CODE> used the symbol from the file which
+ appears first in arguments of the <CODE>PPCLink</CODE> command. For this
+ reason, you will usually want the PythonCore and any other shared libraries
+ which are not part of the standard MPW runtime environment to appear before
+ the standard runtime libraries. This is particularly the case with
+ StdCLib. The "-d" option turns off the (often copious) warnings about
+ multiply defined symbols.
+ <LI>You will want to make sure that the <CODE>HAVE_CONFIG_H</CODE>
+ preprocessor symbol is defined for most C source files using the <CODE>-d
+ HAVE_CONFIG_H</CODE> option to <CODE>MrC</CODE>.
+</UL>
+
+<P>
+The file <A HREF="xx.ppc.slb.make.sit.hqx"><CODE>xx.ppc.slb.make</CODE></A>
+is included here for you to use as a starting point.
+</P>
+
+<H2><A NAME="using">Using the Extension Module</A></H2>
+
+<P>
+Once you have compiled your extension module, you will need to let Python
+know where it is. You can either move it into a place on Python's search
+path - such as the <CODE>:Mac:Plugins</CODE> folder - or modify the path to
+include the location of your new module using the
+<CODE>EditPythonPrefs</CODE> applet.
+</P>
+
+<P>
+Your work may not be completely done, as many extension modules have a
+Python wrapper around them. If the Python was not written with portability
+in mind, you may need to do some more work to get that up and running.
+Indeed, if the Python part uses OS-specific features, like pipes, you may
+have to completely rewrite it if you can make it work at all.
+</P>
+
+<H2><A NAME="problems">Common Problems</A></H2>
+
+<P>
+There are a couple of common problems which occur when porting a module
+from another platform. Fortunately, they are often easy to fix.
+</P>
+
+<H3>Static Forward Definitions</H3>
+
+<P>
+If you get a compiler error which looks something like:
+</P>
+
+<PRE>
+File "xxmodule.c"; line 135 #Error: 'Xxo_Type' is already defined
+</PRE>
+
+<P>
+then most likely either you have not set up <CODE>config.h</CODE> correctly
+to handle static forward definitions, or the module author has not adhered
+to the standard python conventions. If the second is the case, find where
+the variable is first defined, and replace the <CODE>static</CODE> with
+<CODE>staticforward</CODE>. Then find the second place it is defined
+(usually the line where the compiler complained) and replace
+<CODE>static</CODE> with <CODE>statichere</CODE>.
+</P>
+
+<P>
+If you have set up things correctly, you should now be able to compile.
+</P>
+
+<H3>Automatic Type Conversion</H3>
+
+<P>
+<CODE>MrC</CODE> seems to be a little pickier about automatically
+converting from one type to another than some other C compilers. These can
+often be fixed by simply adding an explicit cast to the desired type.
+</P>
+
+<P>
+XXX There may be a compiler option which relaxes this. That would be a
+better solution.
+</P>
+
+<H2><A NAME="caveats">Caveats</A></H2>
+
+<P>
+As Jack Jansen pointed out on the Mac Python mailing list, there could
+potentially be conflicts between the MetroWerks C runtime which the Python
+core and standard modules was compiled with, and the MPW C runtime which
+your extension module is compiled with. While things seem to work fine in
+everyday use, it is possible that there are bugs which have not been
+discovered yet. Most likely these world take the form of standard C
+functions (most likely I/O functions due to conflicts between the SIOUX
+libraries and the SIOW libraries) not working as they are supposed to, or
+memory leaks caused by improper malloc/free.
+</P>
+
+<P>
+Some such problems have been demonstrated by compiling modules with
+PythonCore linked after StdCLib - printf does not work properly in this
+setup, and I suspect that there will also be malloc/free problems in
+situations where the module allocates memory which is later disposed of by
+Python, or vice-versa. Compiling with PythonCore taking precedence over
+StdCLib seems to give the correct behaviour.
+</P>
+
+<P>
+This method of compiling should be considered experimental for the time
+being. <STRONG>Use it at your own risk.</STRONG>
+</P>
+
+<P>
+If you notice any quirks in modules compiled this way, or have insight into
+what may go wrong or right with this situation, <A
+HREF="mailto:cwebster@nevada.edu">please contact me</A> so that I can add
+it to the HOWTO.
+</P>
+
+<P>
+The ideal solution to this problem would be to get Python to compile using
+MPW (and a Python MPW Tool would be very neat indeed). However, that does
+seem to be a major project.
+</P>
+
+<DIV class=footer>
+<HR>
+<BR>
+©<A HREF="mailto:cwebster@nevada.edu">Corran Webster</A>, 1999. <BR>
+<!-- #LASTMODIFIED TEXT="Last modified" FORM="SHORT,TIME" -->
+Last modified 14/12/99 12:17 PM
+<!-- /#LASTMODIFIED -->
+</DIV>
+
+</BODY>
+
+</HTML>