Example Cython project with sharing between pyx file and plain C file

foo.pyx

cdef public void hello():
    print "Hello world!"

fooutil.c

#include <stdio.h>
#include <Python.h>  /* Required for foo.h to work--should probably be included directly in foo.h */
#include "foo.h"


void greeting(void) {
    hello();
}

setup.py

from setuptools import setup, Extension
from Cython.Build import cythonize


ext = cythonize(Extension('foo', sources=['foo.pyx', 'fooutil.c']))

setup(
    name='foo',
    version='0.1',
    py_modules=['foo'],
    ext_modules=ext
)