#!/usr/bin/env python

"""Simple examples of calling C functions through ctypes module."""

import ctypes

import pathlib

import sys

if __name__ == "__main__":

libname = pathlib.Path().absolute()

print("libname: ", libname)

# Load the shared library into c types.

if sys.platform.startswith("win"):

c_lib = ctypes.CDLL(libname / "cppmult.dll")

else:

c_lib = ctypes.CDLL(libname / "libcppmult.so")

# Sample data for our call:

x, y = 6, 2.3

# This will not work:

# answer = c_lib.cmult(x, y)

# This produces a bad answer:

answer = c_lib.cppmult(x, ctypes.c_float(y))

print(f" In Python: int: {x} float {y:.1f} return val {answer:.1f}")

print()

# You need tell ctypes that the function returns a float

c_lib.cppmult.restype = ctypes.c_float

answer = c_lib.cppmult(x, ctypes.c_float(y))

print(f" In Python: int: {x} float {y:.1f} return val {answer:.1f}")