Detect when a Python module unloads

Question

I have a module that uses ctypes to wrap some functionality from a static library into a class. When the module loads, it calls an initialize function in the static library. When the module is unloaded (presumably when the interpreter exits), there's an unload function in the library that I'd like to be called. How can I create this hook?

Answer 1

Use the atexit module:

import mymodule
import atexit

# call mymodule.unload('param1', 'param2') when the interpreter exits:
atexit.register(mymodule.unload, 'param1', 'param2')

Another simple example from the docs, using register as a decorator:

import atexit

@atexit.register
def goodbye():
    print "You are now leaving the Python sector."