Hi I am new to Cython and I would like to interface with my existing C code and I am having trouble linking my program.
I have had a regular cython module working plenty of times before now I would like to interface with my C code just to be clear.
Here is what my directory structure look like:
Example <-- Master directory opened from here CSourceCode source.c source.h cprogram.pxd program.c program.pyx setup.py testing_interface.py Setup.py
from setuptools import setup, Extension from Cython.Build import cythonize setup ( ext_modules=cythonize([Extension("program", ["program.pyx"])]) ) cprogram.pxd
cdef extern from "CSourceCode/source.h": void hello() source.c
#include <stdio.h> int main(void) { return 0; } void hello() { printf("HELLO FROM C"); } source.h
#ifndef _SOURCE #define _SOURCE "source.h" void hello(); #endif program.pyx
cimport cprogram def hello(): cprogram.hello() testing_interface.py
import program program.hello() trace
python setup.py build_ext -i Compiling program.pyx because it changed. [1/1] Cythonizing program.pyx C:\Users\bmxfi\AppData\Local\Programs\Python\Python39\lib\site-packages\Cython\Compiler\Main.py:369: FutureWarning: Cython directive 'language_level' not set, using 2 for now (Py2). This will change in a later release! File: C:\Users\bmxfi\Desktop\code\CPython\CInterfacing\Example\program.pyx tree = Parsing.p_module(s, pxd, full_module_name) running build_ext building 'program' extension C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\VC\Tools\MSVC\14.16.27023\bin\HostX86\x64\cl.exe /c /nologo /Ox /W3 /GL /DNDEBUG /MD -I. -IC:\Users\bmxfi\AppData\Local\Programs\Python\Python39\include -IC:\Users\bmxfi\AppData\Local\Programs\Python\Python39\include -IC:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\VC\Tools\MSVC\14.16.27023\include -IC:\Program Files (x86)\Windows Kits\10\include\10.0.17763.0\ucrt -IC:\Program Files (x86)\Windows Kits\10\include\10.0.17763.0\shared -IC:\Program Files (x86)\Windows Kits\10\include\10.0.17763.0\um -IC:\Program Files (x86)\Windows Kits\10\include\10.0.17763.0\winrt -IC:\Program Files (x86)\Windows Kits\10\include\10.0.17763.0\cppwinrt /Tcprogram.c /Fobuild\temp.win-amd64-3.9\Release\program.obj program.c C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\VC\Tools\MSVC\14.16.27023\bin\HostX86\x64\link.exe /nologo /INCREMENTAL:NO /LTCG /DLL /MANIFEST:EMBED,ID=2 /MANIFESTUAC:NO /LIBPATH:C:\Users\bmxfi\AppData\Local\Programs\Python\Python39\libs /LIBPATH:C:\Users\bmxfi\AppData\Local\Programs\Python\Python39\PCbuild\amd64 /LIBPATH:C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\VC\Tools\MSVC\14.16.27023\lib\x64 /LIBPATH:C:\Program Files (x86)\Windows Kits\10\lib\10.0.17763.0\ucrt\x64 /LIBPATH:C:\Program Files (x86)\Windows Kits\10\lib\10.0.17763.0\um\x64 /EXPORT:PyInit_program build\temp.win-amd64-3.9\Release\program.obj /OUT:build\lib.win-amd64-3.9\program.cp39-win_amd64.pyd /IMPLIB:build\temp.win-amd64-3.9\Release\program.cp39-win_amd64.lib Creating library build\temp.win-amd64-3.9\Release\program.cp39-win_amd64.lib and object build\temp.win-amd64-3.9\Release\program.cp39-win_amd64.exp program.obj : error LNK2001: unresolved external symbol hello build\lib.win-amd64-3.9\program.cp39-win_amd64.pyd : fatal error LNK1120: 1 unresolved externals error: command 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\BuildTools\\VC\\Tools\\MSVC\\14.16.27023\\bin\\HostX86\\x64\\link.exe' failed with exit code 1120 
