Question

I built a DLL in VS2010 with boost::python to export some function to a python module:

myDLL.cpp:

std::string greet() { return "hello, world"; }
int square(int number) { return number * number; }

BOOST_PYTHON_MODULE(getting_started1)
{
    // Add regular functions to the module.
    def("greet", greet);
    def("square", square);
}

Up to here, everything compiles just fine. I then get the myDLL.dll and myDLL.lib file in c:\myDLL\Debug.

According to boost doc (http://wiki.python.org/moin/boost.python/SimpleExample), I need to add this to PYTHONPATH, so I added c:\myDLL\Debug to it:
PYTHONPATH:
C:\Python27;c:\myDLL\Debug;

then, from my .py file, I try to import it:

import getting_started1
print getting_started1.greet()
number = 11
print number, '*', number, '=', getting_started1.square(number)

I have also tried from myDLL import getting_started1, and from getting_started1 import *, and all possible combinations of sorts.

Can anyone tell me how am I supposed to call my module? Thanks

EDIT:
According to cgohlke, there should be a getting_started1.pyd somewhere in my PYTHONPATH when I compile in VS? This file is inexistant… Do I have to set somethign different in VS2010? I have a default win32 DLL project.
But the boost doc says ” If we build this shared library and put it on our PYTHONPATH”, isn’t a shared library on windows a DLL? ergo, the DLL should be in the PYTHONPATH?

Answer 1

The standard, portable way to build Python extensions is via distutils. However, Visual Studio 2010 is not a supported compiler for Python 2.7. The following setup.py works for me with Visual Studio 2008 and boost_1_48_0. The build command is python setup.py build_ext --inplace.

# setup.py
from distutils.core import setup
from distutils.extension import Extension
setup(name="getting_started1",
    ext_modules=[
        Extension("getting_started1", ["getting_started1.cpp"],
        include_dirs=['boost_1_48_0'],
        libraries = ['boost_python-vc90-mt-1_48'],
        extra_compile_args=['/EHsc', '/FD', '/DBOOST_ALL_DYN_LINK=1']
        )
    ])

For your Visual Studio 2010 project, try to change the linker output file to getting_started1.pyd instead of myDLL.dll.