#!/usr/bin/env python

import os
import sys
import time

def show_waitpid_results(results):
    print("results: %s" % (str(results)))
    print("core: %r continued: %r stopped: %r signaled: %r exited %r" %
        (
            os.WCOREDUMP(results[1]),
            os.WIFCONTINUED(results[1]),
            os.WIFSTOPPED(results[1]),
            os.WIFSIGNALED(results[1]),
            os.WIFEXITED(results[1]))
        )
    if os.WIFEXITED(results[1]):
        print("exit code: %r" % (os.WEXITSTATUS(results[1])))

if __name__ == '__main__':
    try:
        pid = os.fork()
        if pid:
            print("in parent. child pid: %r" % (pid))
            while True:
                waitpid_result = os.waitpid(pid, os.WNOHANG)
                show_waitpid_results(waitpid_result)
                if waitpid_result == (0,0) or waitpid_result == (0,-512):
                    time.sleep(.1)
                else:
                    break
            print("parent exiting")
        else:
            # child
            time.sleep(.5)
            print("child exiting with exit code 10");
            sys.exit(10)
    except Exception:
        e = sys.exc_info()[1]
        print("error: %s"%(e))
        sys.exit(20)