interfacing C with Python

[Skaperen]

starting to read up on interfacing C with Python. the first impression i get is that a lot of effort is being made to make Python bend down to the way C does things. i'd rather work with a API subset where C code must be coded Python-aware. a C function called from a Python script would get arguments in the form Python works with, with perhaps a set of C macros or functions that helps the C code work with it. the C code would then have to build the value to be returned and call a function to actually give them to be returned (else a return from C just returns a None). is there anything that does a C interface like this? all my intentions for C will be Python aware, or i will do the calls to unaware code in C.

[Gribouillis]

I'm not an expert in interfacing Python and C but I think the default API already works the way you described above. Extension modules use Python-aware C functions that get arguments in the form Python works with and parse them with the C macro PyArg_ParseTuple. When they return Python values they use the macro Py_BuildValue to create them. The problem with this API is that it forces you to write a lot of hybrid code, take care of reference counts, etc, so it is a slow process.

Before you jump into this, it would be a good idea to review existing tools that already interface Python and C as it is an old problem and many solutions have been developped, starting with the ctypes module, the Cython language, the Swig module. In my bookmarks, there are 3 modern modules that try to minimize the amount of boilerplate code and could be worth exploring, cffi, cppyy and pybind11.

[Skaperen]

i was seeing a bunch of Python functions or classes for Python code to be able to do things that C needs like converting an int to 16 bits, or constructing arguments for a C function. i'm on pause right now due to a major hardware issue. to deal with that, i need to move to my backup laptop that still has a very old Ubuntu (14.04) on it. it needs a fresh install to be normal to me but i decided this is a good time to upgrade from 18.04 to 20.04. i'm also re-arranging partitions so / has more space. this laptop will become a compact server.