Pickle ctypes _FuncPtr

gistfile1.py

class PickleableCtypesFuncPtr:
    """A version of a ctypes._FuncPtr that can be pickled. The shared library
    must be available in the depickling environment.
    """
    def __init__(self, dll_type, lib, name):
        self.__setstate__((dll_type, lib, name))

    def __setstate__(self, state):
        self.state = state
        dll_type, lib, func = self.state
        dll_loader = getattr(ctypes, dll_type)
        self.funcptr = dll_loader(lib)[func]

    def __getstate__(self):
        return self.state

    def __call__(self, *args):
        return self.funcptr(*args)


_libc_name = ctypes.util.find_library("c")
_usleep = PickleableCtypesFuncPtr('PyDLL', _libc_name, 'usleep')