tempfile.py 文件源码

def _mkstemp_inner(dir, pre, suf, flags, output_type):
    """Code common to mkstemp, TemporaryFile, and NamedTemporaryFile."""

    names = _get_candidate_names()
    if output_type is bytes:
        names = map(_os.fsencode, names)

    for seq in range(TMP_MAX):
        name = next(names)
        file = _os.path.join(dir, pre + name + suf)
        try:
            fd = _os.open(file, flags, 0o600)
        except FileExistsError:
            continue    # try again
        except PermissionError:
            # This exception is thrown when a directory with the chosen name
            # already exists on windows.
            if (_os.name == 'nt' and _os.path.isdir(dir) and
                _os.access(dir, _os.W_OK)):
                continue
            else:
                raise
        return (fd, _os.path.abspath(file))

    raise FileExistsError(_errno.EEXIST,
                          "No usable temporary file name found")


# User visible interfaces.