IPython Interactive Computing and Visualization Cookbook

Wrapping a C library in Python with ctypes

Wrapping a C library in Python allows us to leverage existing C code or to implement a critical part of the code in a fast language such as C.

It is relatively easy to use externally-compiled libraries with Python. The first possibility is to call a command-line executable with an os.system command, but this method does not extend to compiled libraries (on Windows, Dynamically Linked Libraries, or DLLs). A more powerful method consists of using a native Python module called ctypes. This module allows us to call functions defined in a compiled library (written in C) from Python. The ctypes module takes care of the data type conversions between C and Python. In addition, the numpy.ctypeslib module provides ...