diff options
| -rw-r--r-- | Doc/using/cmdline.rst | 3 | ||||
| -rw-r--r-- | Doc/whatsnew/3.0.rst | 10 |
2 files changed, 9 insertions, 4 deletions
diff --git a/Doc/using/cmdline.rst b/Doc/using/cmdline.rst index c73f1e0..9274d8e 100644 --- a/Doc/using/cmdline.rst +++ b/Doc/using/cmdline.rst @@ -247,7 +247,8 @@ Miscellaneous options Force the binary layer of the stdin, stdout and stderr streams (which is available as their ``buffer`` attribute) to be unbuffered. The text I/O - layer will still be line-buffered. + layer will still be line-buffered if writing to the console, or + block-buffered if redirected to a non-interactive file. See also :envvar:`PYTHONUNBUFFERED`. diff --git a/Doc/whatsnew/3.0.rst b/Doc/whatsnew/3.0.rst index 523b34e..55b65ba 100644 --- a/Doc/whatsnew/3.0.rst +++ b/Doc/whatsnew/3.0.rst @@ -301,6 +301,12 @@ changed. There is no longer any need for using the encoding-aware streams in the :mod:`codecs` module. +* The initial values of :data:`sys.stdin`, :data:`sys.stdout` and + :data:`sys.stderr` are now unicode-only text files (i.e., they are + instances of :class:`io.TextIOBase`). To read and write bytes data + with these streams, you need to use their :data:`io.TextIOBase.buffer` + attribute. + * Filenames are passed to and returned from APIs as (Unicode) strings. This can present platform-specific problems because on some platforms filenames are arbitrary byte strings. (On the other hand, @@ -511,9 +517,7 @@ consulted for longer descriptions. produces a literal of type :class:`bytes`. * :ref:`pep-3116`. The :mod:`io` module is now the standard way of - doing file I/O, and the initial values of :data:`sys.stdin`, - :data:`sys.stdout` and :data:`sys.stderr` are now instances of - :class:`io.TextIOBase`. The built-in :func:`open` function is now an + doing file I/O. The built-in :func:`open` function is now an alias for :func:`io.open` and has additional keyword arguments *encoding*, *errors*, *newline* and *closefd*. Also note that an invalid *mode* argument now raises :exc:`ValueError`, not |