#!/usr/bin/env python

#from __future__ import print_function

import ctypes
import threading

lib = ctypes.CDLL('./lib.so')

callback_t = ctypes.CFUNCTYPE(None)
lib.callback.argtypes = [ callback_t ]
lib.callback.restype = ctypes.c_int

lc = threading.local()

def callback_fn():
    if hasattr(lc, 'x'):
       print("Python callback_fn called, lc.x = %d" % lc.x)
    else:
       lc.x = 42
       print("Python callback_fn called, setting lc.x = %d" % lc.x)


res = lib.callback(callback_t(callback_fn))

if res != 0:
    raise SystemExit('lib.callback() failed')