def __init__(self, cmd, inputstream=None, buffer_size=65536,

                 chunk_size=4096, starting_values=[], **kwargs):

        """

        Initializes SubprocessIOChunker

        :param cmd: A Subprocess.Popen style "cmd". Can be string or array of strings

        :param inputstream: (Default: None) A file-like, string, or file pointer.

        :param buffer_size: (Default: 65536) A size of total buffer per stream in bytes.

        :param chunk_size: (Default: 4096) A max size of a chunk. Actual chunk may be smaller.

        :param starting_values: (Default: []) An array of strings to put in front of output que.

        """

        if inputstream:

            input_streamer = StreamFeeder(inputstream)

            input_streamer.start()

            inputstream = input_streamer.output

        _shell = kwargs.get('shell', True)

        if isinstance(cmd, (list, tuple)):

            cmd = ' '.join(cmd)

        kwargs['shell'] = _shell

        _p = subprocess.Popen(cmd, bufsize=-1,

                              stdin=inputstream,

                              stdout=subprocess.PIPE,

                              stderr=subprocess.PIPE,

                              **kwargs)

        bg_out = BufferedGenerator(_p.stdout, buffer_size, chunk_size,

                                   starting_values)

        bg_err = BufferedGenerator(_p.stderr, 16000, 1, bottomless=True)

        while not bg_out.done_reading and not bg_out.reading_paused and not bg_err.length:

            # doing this until we reach either end of file, or end of buffer.

            bg_out.data_added_event.wait(1)

            bg_out.data_added_event.clear()

        # at this point it's still ambiguous if we are done reading or just full buffer.

        # Either way, if error (returned by ended process, or implied based on

        # presence of stuff in stderr output) we error out.

        # Else, we are happy.

        _returncode = _p.poll()

        if _returncode or (_returncode is None and bg_err.length):

            try:

                _p.terminate()

            except Exception:

                pass

            bg_out.stop()

            bg_err.stop()

                raise EnvironmentError(

                    "Subprocess exited due to an error:\n" + err)

            raise EnvironmentError(

                "Subprocess exited with non 0 ret code:%s" % _returncode)

        self.process = _p

        self.output = bg_out

        self.error = bg_err

        self.inputstream = inputstream

    def __iter__(self):

        return self

    def next(self):

            err = '%s' % ''.join(self.error)

            raise EnvironmentError("Subprocess exited due to an error:\n" + err)

        return self.output.next()

    def throw(self, type, value=None, traceback=None):

        if self.output.length or not self.output.done_reading:

            raise type(value)

    def close(self):

        try:

            self.process.terminate()

        except:

            pass

        try:

            self.output.close()

        except:

            pass

        try:

            self.error.close()

        except:

            pass

        try:

            os.close(self.inputstream)

        except:

            pass

    def __del__(self):

        self.close()