cmd2.py 文件源码

def _restore_output(self, statement):
        """Handles restoring state after output redirection as well as the actual pipe operation if present.

        :param statement: ParsedString - subclass of str which also contains pyparsing ParseResults instance
        """
        # If we have redirected output to a file or the clipboard or piped it to a shell command, then restore state
        if self.kept_state is not None:
            # If we redirected output to the clipboard
            if statement.parsed.output and not statement.parsed.outputTo:
                self.stdout.seek(0)
                write_to_paste_buffer(self.stdout.read())

            try:
                # Close the file or pipe that stdout was redirected to
                self.stdout.close()
            except BROKEN_PIPE_ERROR:
                pass
            finally:
                # Restore self.stdout
                self.kept_state.restore()
                self.kept_state = None

            # If we were piping output to a shell command, then close the subprocess the shell command was running in
            if self.pipe_proc is not None:
                self.pipe_proc.communicate()
                self.pipe_proc = None

        # Restore sys.stdout if need be
        if self.kept_sys is not None:
            self.kept_sys.restore()
            self.kept_sys = None