mailbox.py 文件源码

def __init__(self, path, factory=None, create=True):
        """Initialize a single-file mailbox."""
        Mailbox.__init__(self, path, factory, create)
        try:
            f = open(self._path, 'rb+')
        except IOError, e:
            if e.errno == errno.ENOENT:
                if create:
                    f = open(self._path, 'wb+')
                else:
                    raise NoSuchMailboxError(self._path)
            elif e.errno in (errno.EACCES, errno.EROFS):
                f = open(self._path, 'rb')
            else:
                raise
        self._file = f
        self._toc = None
        self._next_key = 0
        self._pending = False   # No changes require rewriting the file.
        self._locked = False
        self._file_length = None        # Used to record mailbox size