Hi everyone, I'm trying to use a shared library created in Cython. example.

*********file run_cython.pyx******************************

cpdef int test(int x):
    cdef int y = 1
    cdef int i
    for i in range(1, x+1):
        y *= i
    return y
***********************************************************

************file setup.py*********************************

from distutils.core import setup
from Cython.Build import cythonize

setup(ext_modules = cythonize('run_cython.pyx'))

*********************************************************

****file Gethello.d**************************************
import core.stdc.stdio;
import core.stdc.stdlib;
import core.sys.posix.dlfcn;

extern (C) int test();

int main()
{
    int x;
    x = 2;
    printf("+main()\n");
    void* lh = dlopen("run_cython.so", RTLD_LAZY);
    if (!lh)
    {
        fprintf(stderr, "dlopen error: %s\n", dlerror());
        exit(1);
    }
    printf("libsubs.so is loaded\n");
    int function() fn = cast(int function())dlsym(lh, "test");
    char* error = dlerror();
    if (error)
    {
        fprintf(stderr, "dlsym error: %s\n", error);
        exit(1);
    }
    printf("dll() function is found\n");
    fn();
    printf("unloading run_cython.so\n");
    dlclose(lh);
    printf("-main()\n");
    return 0;
}

************************************************************************

I am using the following commands to compile

python setup.py build_ext --inplace
dmd Gethello.d
dmd Gethello.o  -defaultlib=libphobos2.so -L-rpath=/home/affonso/Desktop/lab7

The program compiles but the error message appears when I run it. dlsym error:

how can I use the shared library generated by cython in dlang? or how do I fix this error?

Thank you very much in advance.

On Sunday, 11 April 2021 at 20:08:15 UTC, affonso elias ferreira junior wrote:
> Hi everyone, I'm trying to use a shared library created in Cython. example.
>
> [...]

I am on my mobile phone, and cannot reproduce. But i see that this cast(int function()) should be cast(int function(int)). Try correcting function signatures throughout the code. And extern (c) int test() is irrelevant here because you are loading it via a different mechanism.