| **************************** |
| What's New In Python 3.3 |
| **************************** |
| |
| :Author: Raymond Hettinger |
| :Release: |release| |
| :Date: |today| |
| |
| .. $Id$ |
| Rules for maintenance: |
| |
| * Anyone can add text to this document. Do not spend very much time |
| on the wording of your changes, because your text will probably |
| get rewritten to some degree. |
| |
| * The maintainer will go through Misc/NEWS periodically and add |
| changes; it's therefore more important to add your changes to |
| Misc/NEWS than to this file. |
| |
| * This is not a complete list of every single change; completeness |
| is the purpose of Misc/NEWS. Some changes I consider too small |
| or esoteric to include. If such a change is added to the text, |
| I'll just remove it. (This is another reason you shouldn't spend |
| too much time on writing your addition.) |
| |
| * If you want to draw your new text to the attention of the |
| maintainer, add 'XXX' to the beginning of the paragraph or |
| section. |
| |
| * It's OK to just add a fragmentary note about a change. For |
| example: "XXX Describe the transmogrify() function added to the |
| socket module." The maintainer will research the change and |
| write the necessary text. |
| |
| * You can comment out your additions if you like, but it's not |
| necessary (especially when a final release is some months away). |
| |
| * Credit the author of a patch or bugfix. Just the name is |
| sufficient; the e-mail address isn't necessary. |
| |
| * It's helpful to add the bug/patch number as a comment: |
| |
| % Patch 12345 |
| XXX Describe the transmogrify() function added to the socket |
| module. |
| (Contributed by P.Y. Developer.) |
| |
| This saves the maintainer the effort of going through the SVN log |
| when researching a change. |
| |
| This article explains the new features in Python 3.3, compared to 3.2. |
| |
| |
| PEP XXX: Stub |
| ============= |
| |
| |
| Other Language Changes |
| ====================== |
| |
| Some smaller changes made to the core Python language are: |
| |
| * Stub |
| |
| |
| New, Improved, and Deprecated Modules |
| ===================================== |
| |
| * Stub |
| |
| codecs |
| ------ |
| |
| Multibyte CJK decoders now resynchronize faster. They only ignore the first |
| byte of an invalid byte sequence. For example, ``b'\xff\n'.decode('gb2312', |
| 'replace')`` now returns a ``\n`` after the replacement character. |
| |
| (:issue:`12016`) |
| |
| Don't reset incremental encoders of CJK codecs at each call to their encode() |
| method anymore. For example:: |
| |
| $ ./python -q |
| >>> import codecs |
| >>> encoder = codecs.getincrementalencoder('hz')('strict') |
| >>> b''.join(encoder.encode(x) for x in '\u52ff\u65bd\u65bc\u4eba\u3002 Bye.') |
| b'~{NpJ)l6HK!#~} Bye.' |
| |
| This example gives ``b'~{Np~}~{J)~}~{l6~}~{HK~}~{!#~} Bye.'`` with older Python |
| versions. |
| |
| (:issue:`12100`) |
| |
| curses |
| ------ |
| |
| The :class:`curses.window` class has a new :class:`~curses.window.get_wch` |
| method to a wide character. Patch by Iñigo Serna. |
| |
| (:issue:`6755`) |
| |
| faulthandler |
| ------------ |
| |
| New module: :mod:`faulthandler`. |
| |
| * :envvar:`PYTHONFAULTHANDLER` |
| * :option:`-X` ``faulthandler`` |
| |
| |
| math |
| ---- |
| |
| The :mod:`math` module has a new function: |
| |
| * :func:`~math.log2`: return the base-2 logarithm of *x* |
| (Written by Mark Dickinson in :issue:`11888`). |
| |
| |
| nntplib |
| ------- |
| |
| The :class:`nntplib.NNTP` class now supports the context manager protocol to |
| unconditionally consume :exc:`socket.error` exceptions and to close the NNTP |
| connection when done:: |
| |
| >>> from nntplib import NNTP |
| >>> with NNTP('news.gmane.org') as n: |
| ... n.group('gmane.comp.python.committers') |
| ... |
| ('211 1754 1 1754 gmane.comp.python.committers', 1754, 1, 1754, 'gmane.comp.python.committers') |
| >>> |
| |
| (Contributed by Giampaolo Rodolà in :issue:`9795`) |
| |
| |
| os |
| -- |
| |
| * The :mod:`os` module has a new :func:`~os.pipe2` function that makes it |
| possible to create a pipe with :data:`~os.O_CLOEXEC` or |
| :data:`~os.O_NONBLOCK` flags set atomically. This is especially useful to |
| avoid race conditions in multi-threaded programs. |
| |
| * The :mod:`os` module has a new :func:`~os.sendfile` function which provides |
| an efficent "zero-copy" way for copying data from one file (or socket) |
| descriptor to another. The phrase "zero-copy" refers to the fact that all of |
| the copying of data between the two descriptors is done entirely by the |
| kernel, with no copying of data into userspace buffers. :func:`~os.sendfile` |
| can be used to efficiently copy data from a file on disk to a network socket, |
| e.g. for downloading a file. |
| |
| (Patch submitted by Ross Lagerwall and Giampaolo Rodolà in :issue:`10882`.) |
| |
| * The :mod:`os` module has two new functions: :func:`~os.getpriority` and |
| :func:`~os.setpriority`. They can be used to get or set process |
| niceness/priority in a fashion similar to :func:`os.nice` but extended to all |
| processes instead of just the current one. |
| |
| (Patch submitted by Giampaolo Rodolà in :issue:`10784`.) |
| |
| |
| packaging |
| --------- |
| |
| :mod:`distutils` has undergone additions and refactoring under a new name, |
| :mod:`packaging`, to allow developers to break backward compatibility. |
| :mod:`distutils` is still provided in the standard library, but users are |
| encouraged to transition to :mod:`packaging`. For older versions of Python, a |
| backport compatible with 2.4+ and 3.1+ will be made available on PyPI under the |
| name :mod:`distutils2`. |
| |
| .. TODO add examples and howto to the packaging docs and link to them |
| |
| |
| pydoc |
| ----- |
| |
| The Tk GUI and the :func:`~pydoc.serve` function have been removed from the |
| :mod:`pydoc` module: ``pydoc -g`` and :func:`~pydoc.serve` have been deprecated |
| in Python 3.2. |
| |
| |
| sys |
| --- |
| |
| * The :mod:`sys` module has a new :func:`~sys.thread_info` :term:`struct |
| sequence` holding informations about the thread implementation. |
| |
| (:issue:`11223`) |
| |
| |
| signal |
| ------ |
| |
| * The :mod:`signal` module has new functions: |
| |
| * :func:`~signal.pthread_sigmask`: fetch and/or change the signal mask of the |
| calling thread (Contributed by Jean-Paul Calderone in :issue:`8407`) ; |
| * :func:`~signal.pthread_kill`: send a signal to a thread ; |
| * :func:`~signal.sigpending`: examine pending functions ; |
| * :func:`~signal.sigwait`: wait a signal. |
| * :func:`~signal.sigwaitinfo`: wait for a signal, returning detailed |
| information about it. |
| * :func:`~signal.sigtimedwait`: like :func:`~signal.sigwaitinfo` but with a |
| timeout. |
| |
| * The signal handler writes the signal number as a single byte instead of |
| a nul byte into the wakeup file descriptor. So it is possible to wait more |
| than one signal and know which signals were raised. |
| |
| * :func:`signal.signal` and :func:`signal.siginterrupt` raise an OSError, |
| instead of a RuntimeError: OSError has an errno attribute. |
| |
| |
| ssl |
| --- |
| |
| The :mod:`ssl` module has new functions: |
| |
| * :func:`~ssl.RAND_bytes`: generate cryptographically strong |
| pseudo-random bytes. |
| * :func:`~ssl.RAND_pseudo_bytes`: generate pseudo-random bytes. |
| |
| |
| ftplib |
| ------ |
| |
| The :class:`~ftplib.FTP_TLS` class now provides a new |
| :func:`~ftplib.FTP_TLS.ccc` function to revert control channel back to |
| plaintex. This can be useful to take advantage of firewalls that know how to |
| handle NAT with non-secure FTP without opening fixed ports. |
| |
| (Contributed by Giampaolo Rodolà in :issue:`12139`) |
| |
| |
| shutil |
| ------ |
| |
| The :mod:`shutil` module has a new :func:`~shutil.disk_usage` function providing total, |
| used and free disk space statistics. |
| |
| (Contributed by Giampaolo Rodolà in :issue:`12442`) |
| |
| |
| Optimizations |
| ============= |
| |
| Major performance enhancements have been added: |
| |
| * Stub |
| |
| |
| Build and C API Changes |
| ======================= |
| |
| Changes to Python's build process and to the C API include: |
| |
| * Stub |
| |
| |
| Unsupported Operating Systems |
| ============================= |
| |
| OS/2 and VMS are no longer supported due to the lack of a maintainer. |
| |
| Windows 2000 and Windows platforms which set ``COMSPEC`` to ``command.com`` |
| are no longer supported due to maintenance burden. |
| |
| |
| Porting to Python 3.3 |
| ===================== |
| |
| This section lists previously described changes and other bugfixes |
| that may require changes to your code: |
| |
| * Stub |
| |
| |
| .. Issue #11591: When :program:`python` was started with :option:`-S`, |
| ``import site`` will not add site-specific paths to the module search |
| paths. In previous versions, it did. See changeset for doc changes in |
| various files. Contributed by Carl Meyer with editions by Éric Araujo. |
| |
| .. Issue #10998: -Q command-line flags are related artifacts have been |
| removed. Code checking sys.flags.division_warning will need updating. |
| Contributed by Éric Araujo. |