Call C code from Python

~2 mins read

You can use ctypes or cffi to call C code from Python.

Using ctypes

1. Create a C Library

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   // example.c
   #include <stdio.h>
   
   void hello() {
       printf("Hello from C!\n");
   }
   

2. Compile to Shared Library

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   gcc -shared -o libexample.so -fPIC example.c
   

3. Use in Python

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   import ctypes
   
   # Load the shared library
   lib = ctypes.CDLL('./libexample.so')
   
   # Call the function
   lib.hello()
   

Using cffi

1. Create a C Library

   Same as above.

2. Compile to Shared Library

   Same as above.

3. Use in Python

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   from cffi import FFI
   
   ffi = FFI()
   
   # Load the shared library
   lib = ffi.dlopen('./libexample.so')
   
   # Define the function prototype
   ffi.cdef('void hello();')
   
   # Call the function
   lib.hello()