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diff --git a/Mac/Demo/mpwextensions.html b/Mac/Demo/mpwextensions.html deleted file mode 100644 index 742cbc2..0000000 --- a/Mac/Demo/mpwextensions.html +++ /dev/null @@ -1,484 +0,0 @@ -<!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> |