Have you ever came across the situation where you have to call C function using python? This article is going to help you on a very basic level and if you have not come across any situation like this, you enjoy knowing how it is possible.
First, let’s write one simple function using C and generate a shared library of the file. Let’s say file name is function.c.
Python is a high-level programming language that is easy to learn and use. However, sometimes you may need to use a C library or function in your Python code. Fortunately, Python provides an interface to call C functions using the ctypes library. Here's a simple example of how to call a C function from Python:
Assuming we have a C function that calculates the factorial of a number, and the function is defined in a shared library named libfactorial.so, we can call this function from Python using the ctypes library as follows:
import ctypes # Load the shared library lib = ctypes.cdll.LoadLibrary('./libfactorial.so') # Define the argument and return types of the function lib.factorial.argtypes = [ctypes.c_int] lib.factorial.restype = ctypes.c_int # Call the function n = 5 result = lib.factorial(n) print(f"The factorial of {n} is {result}")
In the above code, we first load the shared library containing the C function using ctypes.cdll.LoadLibrary
. We then define the argument and return types of the function using argtypes
and restype
, respectively. Finally, we call the function by passing the argument n
and storing the result in the variable result
. We then print the result using print
.
Note that the argtypes
and restype
attributes are essential to ensure that the correct data types are used when calling the C function. If these are not set correctly, the function may not work as expected.