Hi, Thanks for your help. I can now build the module and import and use it in Python (using SWIG)!
Regarding Boost.Python, I am unable to run bjam successfully. I get the following error: user409:~/boosttest siddarthakrishnan$ ls Jamfile Jamrules hello.cpp user409:~/boosttest siddarthakrishnan$ bjam -sTOOLS=darwin Failed to find the project root for directory '.'. Did not find a project-root.jam file there or in any of its parent directories. Please consult the documentation at 'http://www.boost.org'. I have changed the project root path in Jamrules to the Boost directory. project-root.jam is in the directory. Does anyone know how to solve this error. Thanks, Siddartha On 6-Jul-06, at 2:37 PM, Kent Quirk wrote: > Siddartha Krishnan wrote: >> I'm new to using SWIG for python. I am having several problems >> creating a C++ extension module for python. I am using OS X 10.4 >> with python 2.4 and SWIG 1.3.29 (using darwinports). >> >> I can use SWIG and distutils in order to make a C extension >> module for python, however, I cannot do so for a C++ extension >> module - I get an import error: >> >> mie-15-203:~/swig/class_test siddarthakrishnan$ python mymod.py >> Traceback (most recent call last): >> File "mymod.py", line 5, in ? >> import _mymod >> ImportError: Failure linking new module: /Users/siddarthakrishnan/ >> SWIG/class_test/_mymod.so: Symbol not found: __ZN9SomeClassC1Eii >> Referenced from: /Users/siddarthakrishnan/SWIG/class_test/ >> _mymod.so >> Expected in: dynamic lookup >> >> The setup.py file is as follows: >> >> # setup.py >> from distutils.core import setup, Extension >> setup (name = "_mymod", >> version = "1.0", >> maintainer = "Your Name", >> maintainer_email = "[EMAIL PROTECTED]", >> description = "Sample Python C++ Extension", >> ext_modules = [Extension('_mymod', >> sources=['mymod_wrap.cxx'])]) >> >> Does anyone know how to create a setup.py file that works with c+ >> + extension modules? >> >> > I've never used SWIG, but I think your problem is related to name > mangling. > > Because C++ is designed to work with primitive linker technology > (which uses names and only names for symbol resolution), it can't > rely on the linker to be able to put together overloaded functions > properly. If you have functions called abs(float) and abs(int), if > the only name exported was abs, there'd be a conflict. So C++ > "mangles" the names to include type information. > > You can tell C++ to leave the names alone (giving them C linkage > semantics) by using extern "C" like so: > > extern "C" void myfunc(int x) > { > } > > on the routines that you want to make available to Python. > Understand that they'll have to be pure external functions, not > members of classes. > > You should probably read and understand this: > > http://llama.med.harvard.edu/~fgibbons/doc/SWIG1.3.10/Manual/SWIG.html > > If you're into C++ and want to use the power of C++ in conjunction > with Python, consider using boost::python instead of SWIG. > > Kent > Are you linking with all libraries that are needed for the extension? Your module seems to be missing 'SomeClass::SomeClass(int, int)'. If you do the link step that setup.py generates manually, but add '- framework Python' and remove '-undefined surpress' you should get a list of all symbols that aren't present in the extension. However, don't build the final version of the extension like that. Ronald _______________________________________________ Pythonmac-SIG maillist - Pythonmac-SIG@python.org http://mail.python.org/mailman/listinfo/pythonmac-sig
