tempfile.py 文件源码

def NamedTemporaryFile(mode='w+b', buffering=-1, encoding=None,
                       newline=None, suffix="", prefix=template,
                       dir=None, delete=True):
    """Create and return a temporary file.
    Arguments:
    'prefix', 'suffix', 'dir' -- as for mkstemp.
    'mode' -- the mode argument to io.open (default "w+b").
    'buffering' -- the buffer size argument to io.open (default -1).
    'encoding' -- the encoding argument to io.open (default None)
    'newline' -- the newline argument to io.open (default None)
    'delete' -- whether the file is deleted on close (default True).
    The file is created as mkstemp() would do it.

    Returns an object with a file-like interface; the name of the file
    is accessible as file.name.  The file will be automatically deleted
    when it is closed unless the 'delete' argument is set to False.
    """

    if dir is None:
        dir = gettempdir()

    flags = _bin_openflags

    # Setting O_TEMPORARY in the flags causes the OS to delete
    # the file when it is closed.  This is only supported by Windows.
    if _os.name == 'nt' and delete:
        flags |= _os.O_TEMPORARY

    (fd, name) = _mkstemp_inner(dir, prefix, suffix, flags)
    try:
        file = _io.open(fd, mode, buffering=buffering,
                        newline=newline, encoding=encoding)

        return _TemporaryFileWrapper(file, name, delete)
    except Exception:
        _os.close(fd)
        raise