[SOLVED] Python ctypes can not locat existing lib in Docker on Balena

Python ctypes can not locat existing lib in Docker on Balena

I am trying to bind a compiled C-library to my python code with ctypes. I have compiled my library and it works well on my desktop.

However, when I try to run the same code on the Balena platform in a Docker container, it can not locate my library, event though the os-module can find it:

>>> os.path.exists("/app/com/libmylib.so")
True
>>> ctypes.cdll.LoadLibrary("/app/com/libmylib.so")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.8/ctypes/__init__.py", line 451, in LoadLibrary
    return self._dlltype(name)
  File "/usr/local/lib/python3.8/ctypes/__init__.py", line 373, in __init__
    self._handle = _dlopen(self._name, mode)
OSError: /app/com/libmylib.so: cannot open shared object file: No such file or directory

Any ideas as to why it can not find it?

Solution

It turned out, that the library was compiled for the wrong architecture.