Oct 31, 2008 · It's very easy to call a DLL function in Python. I have a self-made DLL file with two functions: add and sub which take two arguments. add(a, b) returns addition of two numbers sub(a, b) returns substraction of two numbers

I always add the directory where my DLL is to the path. That works: os.environ['PATH'] = os.path.dirname(__file__) + ';' + os.environ['PATH'] windll.LoadLibrary('mydll.dll') Note that if you use py2exe, this doesn't work (because __file__ isn't set).

Oct 18, 2008 · If you're talking about Python module DLLs, then simply modifying sys.path should be fine. However, if you're talking about DLLs linked against those DLLs; i.e. a libfoo.dll which a foo.pyd depends on, then you need to modify your PATH environment variable.

Nov 6, 2024 · Here’s a guide detailing the best methods to use DLL files directly within Python, minimizing reliance on external libraries or additional C++ wrapper code. To get started, you can directly use the built-in ctypes library, which allows for simple calling of functions defined in a DLL.

Mar 16, 2025 · You provide the path to the DLL file (e.g., "mydll.dll" or "/path/to/libmydll.so") when you create a PyDLL object. ctypes handles the operating system-specific details of loading the library. import ctypes # Load the DLL (replace with the actual path) mydll = ctypes.PyDLL( "path/to/mydll.dll" ) # On Windows # or mydll = ctypes.PyDLL( "/path/to ...

Mar 16, 2025 · Loads a DLLctypes.WinDLL takes the path to a DLL file as an argument. It loads this DLL into your Python program's memory, making its functions available for use. Accesses functions Once the DLL is loaded, you can access the functions it contains.

Mar 11, 2025 · This tutorial will teach you how to use a DLL file from Python effectively. Learn how to load DLLs, call their functions, and handle errors using the ctypes library. Enhance your Python applications by leveraging existing libraries and optimizing performance.

Feb 18, 2025 · How to Use a DLL in Python. Python provides several methods to interact with DLLs. The most common approach is using the ctypes module, which allows you to call functions in a DLL as if they were Python functions. Key Considerations.

Load the DLL: To load a DLL, you can use the ctypes.CDLL() function (or ctypes.WinDLL() for Windows-specific DLLs). This function takes the path of the DLL file as its argument and returns a library object that can be used to access the functions within the DLL.

Make sure to add the absolute or relative path to the DLL files in the datas statement such as: datas=[('\path\to\API_C.dll', '.'), ('\path\to\API.dll', '.')] The second entry specifies the path, where the DLL should be copied to in the resulting distribution folder.