path: root/Misc/NEWS

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Python News
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(editors: check NEWS.help for information about editing NEWS using ReST.)

What's New in Python 2.6 alpha 1?
=================================

*Release date: XX-XXX-2008*

Core and builtins
-----------------

- Patch #1759: Backport of PEP 3129 class decorators

- Issue #1881: An internal parser limit has been increased. Also see 
  issue 215555 for a discussion.

- Added the future_builtins module, which contains hex() and oct().
  These are the PEP 3127 version of these functions, designed to be
  compatible with the hex() and oct() builtins from Python 3.0.  They
  differ slightly in their output formats from the existing, unchanged
  Python 2.6 builtins.  The expected usage of the future_builtins
  module is:
    from future_builtins import hex, oct

- Issue #1600: Modifed PyOS_ascii_formatd to use at most 2 digit
  exponents for exponents with absolute value < 100.  Follows C99
  standard.  This is a change on Windows, which would use 3 digits.
  Also, added 'n' to the formats that PyOS_ascii_formatd understands,
  so that any alterations it does to the resulting string will be
  available in stringlib/formatter.h (for float.__format__).

- Implemented PEP 3101, Advanced String Formatting.  This adds a new
  builtin format(); a format() method for str and unicode; a
  __format__() method to object, str, unicode, int, long, float, and
  datetime; the class string.Formatter; and the C API
  PyObject_Format().

- Fixed several potential crashes, all caused by specially crafted __del__
  methods exploiting objects in temporarily inconsistent state.

- Issue #2115: Important speedup in setting __slot__ attributes.  Also 
  prevent a possible crash: an Abstract Base Class would try to access a slot 
  on a registered virtual subclass.

- Fixed repr() and str() of complex numbers with infinity or nan as real or
  imaginary part.

- Clear all free list during a gc.collect() of the highest generation in order
  to allow pymalloc to free more arenas. Python may give back memory to the
  OS earlier.

- Issue #2045: Fix an infinite recursion triggered when printing a subclass of
  collections.defaultdict, if its default_factory is set to a bound method.

- Fixed a minor memory leak in dictobject.c. The content of the free
  list was not freed on interpreter shutdown.

- Limit free list of method and builtin function objects to 256 entries
  each.

- Patch #1953: Added ``sys._compact_freelists()`` and the C API functions
  ``PyInt_CompactFreeList`` and ``PyFloat_CompactFreeList``
  to compact the internal free lists of pre-allocted ints and floats.

- Bug #1983: Fixed return type of fork(), fork1() and forkpty() calls.
  Python expected the return type int but the fork familie returns pi_t.

- Issue #1678380: Fix a bug that identifies 0j and -0j when they appear
  in the same code unit.

- Issue #2025 :  Add tuple.count() and tuple.index() methods to comply with
  the collections.Sequence API.

- Patch #1970 by Antoine Pitrou: Speedup unicode whitespace and linebreak
  detection

- Added ``PyType_ClearCache()`` and ``sys._clear_type_cache`` to clear the
  internal lookup cache for ref leak tests.

- Patch #1473257: generator objects gain a gi_code attribute. This is the
  same object as the func_code attribute of the function that produced the
  generator.

- Issue #1920: "while 0" statements were completely removed by the compiler,
  even in the presence of an "else" clause, which is supposed to be run when 
  the condition is false. Now the compiler correctly emits bytecode for the
  "else" suite.

- A few crashers fixed: weakref_in_del.py (issue #1377858);
  loosing_dict_ref.py (issue #1303614, test67.py);
  borrowed_ref_[34].py (not in tracker).

- Issue #1069410: The "can't load dll" message box on Windows is
  suppressed while an extension is loaded by calling SetErrorMode in
  dynload_win.c. The error is still reported properly.

- Bug #1915: Python compiles with --enable-unicode=no again. However
  several extension methods and modules do not work without unicode
  support.

- Issue #1882: when compiling code from a string, encoding cookies in the
  second line of code were not always recognized correctly.

- Issue #1679: "0x" was taken as a valid integer literal.

- Issue #1865: ``bytes`` as an alias for ``str`` and b"" as an alias "" were
  added.

- sys.float_info / PyFloat_GetInfo: The floating point information
  object was converted from a dict to a specialized structseq object.

- Patch #1816: Added sys.flags structseq. It exposes the status of most
  command line arguments and PYTHON* environment variables.

- Objects/structseq.c: Implemented new structseq representation. The patch
  makes structseqs (e.g. the return value of os.stat) more readable.

- Patch #1700288: added a type attribute cache that caches method accesses,
  resulting in speedups in heavily object-oriented code.

- Bug #1776: __import__() no longer accepts filenames on any platform.
  The first parameter to __import__() must be a valid module name.

- Patch #1668: renamed THREADDEBUG envvar to PYTHONTHREADDEBUG.

- Patch #602345: Add -B command line option, PYTHONDONTWRITEBYTECODE envvar
  and sys.dont_write_bytecode attribute. All these can be set to forbid Python
  to attempt to write compiled bytecode files.

- Improve some exception messages when Windows fails to load an extension
  module. Now we get for example '%1 is not a valid Win32 application' instead
  of 'error code 193'.

- Bug #1481296: Fixed long(float('nan'))!=0L.

- Issue #1640: Added math.isinf(x), math.isnan(x) and math.copysign(x, y)
  functions.

- Issue #1635: Platform independent creation and representation of NaN
  and INF. float("nan"), float("inf") and float("-inf") now work on every
  platform with IEEE 754 semantics.

- Compiler now generates simpler and faster code for dictionary literals.
  The oparg for BUILD_MAP now indicates an estimated dictionary size.
  There is a new opcode, STORE_MAP, for adding entries to the dictionary.

- Issue #1638: %zd configure test fails on Linux

- Issue #1620: New property decorator syntax was modifying the decorator
  in place instead of creating a new decorator object.

- Issue #1538: Avoid copying string in split/rsplit if the split
  char is not found.

- Issue #1553: An erroneous __length_hint__ can make list() raise a
  SystemError.

- PEP 366: Allow explicit relative imports when executing modules
  inside packages with the -m switch via a new module level
  __package__ attribute.

- Issue #1402: Fix a crash on exit, when another thread is still running, and
  if the deallocation of its frames somehow calls the PyGILState_Ensure() /
  PyGILState_Release() functions.

- Expose the Py_Py3kWarningFlag as sys.py3kwarning.

- Issue #1445: Fix a SystemError when accessing the ``cell_contents``
  attribute of an empty cell object.

- Issue #1460: The utf-7 incremental decoder did not accept truncated input.
  It now correctly saves its state between chunks of data.

- Patch #1739468: Directories and zipfiles containing a __main__.py file can
  now be directly executed by passing their name to the interpreter. The
  directory/zipfile is automatically inserted as the first entry in sys.path.

- Issue #1265: Fix a problem with sys.settrace, if the tracing function uses a
  generator expression when at the same time the executed code is closing a
  paused generator.

- sets and frozensets now have an isdisjoint() method.

- optimize the performance of builtin.sum().

- Fix warnings found by the new version of the Coverity checker.

- The enumerate() builtin function is no longer bounded to sequences smaller
  than LONG_MAX.  Formerly, it raised an OverflowError.  Now, automatically
  shifts from ints to longs.

- Issue #1686386: Tuple's tp_repr did not take into account the possibility of
  having a self-referential tuple, which is possible from C code.  Nor did
  object's tp_str consider that a type's tp_str could do something that could
  lead to an inifinite recursion.  Py_ReprEnter() and Py_EnterRecursiveCall(),
  respectively, fixed the issues.

- Issue #1164: It was possible to trigger deadlock when using the 'print'
  statement to write to a file since the GIL was not released as needed.  Now
  PyObject_Print() does the right thing along with various tp_print
  implementations of the built-in types and those in the collections module.

- Issue #1147: Exceptions were directly allowing string exceptions in their
  throw() method even though string exceptions no longer allowed.

- Issue #1096: Prevent a segfault from getting the repr of a very deeply nested
  list by using the recursion counter.

- Issue #1202533: Fix infinite recursion calls triggered by calls to
  PyObject_Call() never calling back out to Python code to trigger recursion
  depth updates/checks.  Required the creation of a static RuntimeError
  instance in case normalizing an exception put the recursion check value past
  its limit.  Fixes crashers infinite_rec_(1|2|4|5).py.

- Patch #1031213: Decode source line in SyntaxErrors back to its original source
  encoding.

- Patch #1673759: add a missing overflow check when formatting floats
  with %G.

- Prevent expandtabs() on string and unicode objects from causing a segfault
  when a large width is passed on 32-bit platforms.

- Bug #1733488: Fix compilation of bufferobject.c on AIX.

- Bug #1722485: remove docstrings again when running with -OO.

- Add new attribute names for function objects.  All the func_* become
  __*__ attributes.  (Some already existed, e.g., __doc__ and __name__.)

- Add -3 option to the interpreter to warn about features that are
  deprecated and will be changed/removed in Python 3.0.

- Patch #1686487: you can now pass any mapping after '**' in function
  calls.

- except clauses may now be spelled either "except E, target:" or
  "except E as target:". This is to provide forwards compatibility with
  Python 3.0.

- Deprecate BaseException.message as per PEP 352.

- Bug #1303614: don't expose object's __dict__ when the dict is
  inherited from a builtin base.

- When __slots__ are set to a unicode string, make it work the same as
  setting a plain string, ie don't expand to single letter identifiers.

- Request #1191699:  Slices can now be pickled.

- Request #1193128:  str.translate() now allows a None argument for
  translations that only remove characters without re-mapping the
  remaining characters.

- Patch #1682205: a TypeError while unpacking an iterable is no longer
  masked by a generic one with the message "unpack non-sequence".

- Remove unused file Python/fmod.c.

- Bug #1683368: The object.__init__() and object.__new__() methods are
  now stricter in rejecting excess arguments.  The only time when
  either allows excess arguments is when it is not overridden and the
  other one is.  For backwards compatibility, when both are
  overridden, it is a deprecation warning (for now; maybe a Py3k
  warning later).  Also, type.__init__() insists on the same signature
  as supported by type.__new__().

- Patch #1675423: PyComplex_AsCComplex() now tries to convert an object
  to complex using its __complex__() method before falling back to the
  __float__() method. Therefore, the functions in the cmath module now
  can operate on objects that define a __complex__() method.

- Patch #1623563: allow __class__ assignment for classes with __slots__.
  The old and the new class are still required to have the same slot names.

- Patch #1642547: Fix an error/crash when encountering syntax errors in
  complex if statements.

- Patch #1462488: Python no longer segfaults when ``object.__reduce_ex__()``
  is called with an object that is faking its type.

- Patch #1680015: Don't modify __slots__ tuple if it contains an unicode
  name.

- Patch #1444529: the builtin compile() now accepts keyword arguments.

- Bug #1678647: write a newline after printing an exception in any
  case, even when converting the value to a string failed.

- The dir() function has been extended to call the __dir__() method on
  its argument, if it exists. If not, it will work like before. This allows
  customizing the output of dir() in the presence of a __getattr__().

- Patch #922167: Python no longer segfaults when faced with infinitely
  self-recursive reload() calls (as reported by bug #742342).

- Patch #1675981: remove unreachable code from ``type.__new__()`` method.

- Patch #1491866: change the complex() constructor to allow parthensized
  forms. This means complex(repr(x)) now works instead of raising a
  ValueError.

- Patch #703779: unset __file__ in __main__ after running a file. This
  makes the filenames the warning module prints much more sensible when
  a PYTHONSTARTUP file is used.

- Variant of patch #697613: don't exit the interpreter on a SystemExit
  exception if the -i command line option or PYTHONINSPECT environment
  variable is given, but break into the interactive interpreter just like
  on other exceptions or normal program exit.

- Patch #1638879: don't accept strings with embedded NUL bytes in long().

- Bug #1674503: close the file opened by execfile() in an error condition.

- Patch #1674228: when assigning a slice (old-style), check for the
  sq_ass_slice instead of the sq_slice slot.

- When printing an unraisable error, don't print exceptions. before the name.
  This duplicates the behavior whening normally printing exceptions.

- Bug #1653736: Properly discard third argument to slot_nb_inplace_power.

- PEP 352: Raising a string exception now triggers a TypeError.  Attempting to
  catch a string exception raises DeprecationWarning.

- Bug #1377858: Fix the segfaulting of the interpreter when an object created
  a weakref on itself during a __del__ call for new-style classes (classic
  classes still have the bug).

- Bug #1579370: Make PyTraceBack_Here use the current thread, not the
  frame's thread state.

- patch #1630975: Fix crash when replacing sys.stdout in sitecustomize.py

- Prevent seg fault on shutdown which could occur if an object
  raised a warning.

- Bug #1566280: Explicitly invoke threading._shutdown from Py_Main,
  to avoid relying on atexit.

- Bug #1590891: random.randrange don't return correct value for big number

- Patch #1586791: Better exception messages for some operations on strings,
  tuples and lists.

- Bug #1067760: Deprecate passing floats to file.seek.

- Bug #1591996: Correctly forward exception in instance_contains().

- Bug #1588287: fix invalid assertion for `1,2` in debug builds.

- Bug #1576657: when setting a KeyError for a tuple key, make sure that
  the tuple isn't used as the "exception arguments tuple".

- Bug #1565514, SystemError not raised on too many nested blocks.

- Bug #1576174: WindowsError now displays the windows error code
  again, no longer the posix error code.

- Patch #1549049: Support long values in structmember, issue warnings
  if the assigned value for structmember fields gets truncated.

- Update the peephole optimizer to remove more dead code (jumps after returns)
  and inline unconditional jumps to returns.

- Bug #1545497: when given an explicit base, int() did ignore NULs
  embedded in the string to convert.

- Bug #1569998: break inside a try statement (outside a loop) is now
  recognized and rejected.

- list.pop(x) accepts any object x following the __index__ protocol.

- A number of places, including integer negation and absolute value,
  were fixed to not rely on undefined behaviour of the C compiler
  anymore.

- Bug #1566800: make sure that EnvironmentError can be called with any
  number of arguments, as was the case in Python 2.4.

- Patch #1567691: super() and new.instancemethod() now don't accept
  keyword arguments any more (previously they accepted them, but didn't
  use them).

- Fix a bug in the parser's future statement handling that led to "with"
  not being recognized as a keyword after, e.g., this statement:
  from __future__ import division, with_statement

- Bug #1557232: fix seg fault with def f((((x)))) and def f(((x),)).

- Fix %zd string formatting on Mac OS X so it prints negative numbers.

- Allow exception instances to be directly sliced again.

- Bug #1551432: Exceptions do not define an explicit __unicode__ method.  This
  allows calling unicode() on exceptions classes directly to succeed.

- Bug #1542051: Exceptions now correctly call PyObject_GC_UnTrack.
  Also make sure that every exception class has __module__ set to
  'exceptions'.

- Bug #1550983: emit better error messages for erroneous relative
  imports (if not in package and if beyond toplevel package).

- Overflow checking code in integer division ran afoul of new gcc
  optimizations.  Changed to be more standard-conforming.

- Patch #1542451: disallow continue anywhere under a finally.

- Patch #1546288: fix seg fault in dict_equal due to ref counting bug.

- The return tuple from str.rpartition(sep) is (tail, sep, head) where
  head is the original string if sep was not found.

- Bug #1520864: unpacking singleton tuples in list comprehensions and
  generator expressions (x for x, in ... ) works again.  Fixing this problem
  required changing the .pyc magic number.  This means that .pyc files
  generated before 2.5c2 will be regenerated.

- ``with`` and ``as`` are now keywords.

- Bug #1664966: Fix crash in exec if Unicode filename can't be decoded.

- Issue #1537: Changed GeneratorExit's base class from Exception to
  BaseException.

- Fix Issue #1703448: A joined thread could show up in the
  threading.enumerate() list after the join() for a brief period until
  it actually exited.


Library
-------

- Issue 1781: ConfigParser now does not let you add the "default" section
  (ignore-case)

- Removed uses of dict.has_key() from distutils, and uses of
  callable() from copy_reg.py, so the interpreter now starts up
  without warnings when '-3' is given.  More work like this needs to
  be done in the rest of the stdlib.

- Issue #1916. Added isgenerator() and isgeneratorfunction() to inspect.py.

- #1224: Fixed bad url parsing when path begins with double slash.

- ctypes instances that are not or do not contain pointers can now be
  pickled.

- Patch #1966: Break infinite loop in httplib when the servers
  implements the chunked encoding incorrectly.

- Rename rational.py to fractions.py and the rational.Rational class
  to fractions.Fraction, to avoid the name clash with the abstract
  base class numbers.Rational.  See discussion in issue #1682.

- The pickletools module now provides an optimize() function
  that eliminates unused PUT opcodes from a pickle string.

- #2021: Allow tempfile.NamedTemporaryFile and SpooledTemporaryFile
  to be used in with statements by correctly supporting the context
  management protocol.

- #1979: Add rich comparisons to Decimal, and make Decimal comparisons
  involving a NaN follow the IEEE 754 standard.

- #2004: tarfile.py: Use mode 0700 for temporary directories and default
  permissions for missing directories.

- #175006: The debugger used to skip the condition of a "while" statement
  after the first iteration. Now it correctly steps on the expression, and
  breakpoints on the "while" statement are honored on each loop.

- #1765140: add an optional delay argument to FileHandler and its
  subclasses. Defaults to false (existing behaviour), but if true,
  defers opening the file until the first call to emit().

- The pprint module now supports sets and frozensets.

- #1221598: add optional callbacks to ftplib.FTP's storbinary() and
  storlines() methods.  (Contributed by Phil Schwartz)

- #1715: include sub-extension modules in pydoc's text output.

- #1836: fix an off-by-one bug in TimedRotatingHandler's rollover
  time calculation.

- #1021: fix a bug to allow basicConfig to accept NOTSET as a level.

- #932563: add LoggerAdapter convenience class to make it easier to add
  contextual information in logging output.

- #1760556: fix a bug to avoid FileHandler throwing an exception in
  flush().

- Bug #1530959: distutils' build command now uses different build directory
  when building extension modules against versions of Python compiled
  with ``--with-pydebug``.

- #1555501: move plistlib from plat-mac directory to general library.

- #1269: fix a bug in pstats.add_callers() and add a unit test file for
  pstats.

- #1669: don't allow shutil.rmtree() to be called on a symlink to a
  directory.

- #1664522: in urllib, don't read non-existing directories in ftp mode,
  returning a 0-byte file -- raise an IOError instead.

- #856047: respect the ``no_proxy`` environment variable when using the
  ``http_proxy`` etc. environment variables in urllib.

- #1178141: add a getcode() method to the addinfourls that urllib.open()
  returns so that you can retrieve the HTTP status code.

- Issue #1003: Fix zipfile decryption check, it would fail zip files
  with extended local headers.

- #1189216: Fix the zipfile module to work on archives with headers
  past the 2**31 byte boundary.

- #1336: fix a race condition in subprocess.Popen if the garbage
  collector kicked in at the wrong time that would cause the process
  to hang when the child wrote to stderr.

- #1146: fix how textwrap breaks a long word that would start in the
  last column of a line.

- #1693149: trace.py --ignore-module - accept multiple comma-separated
  modules to be given.

- #1822: MIMEMultipart.is_multipart() behaves correctly for a just-created
  (and empty) instance. Thanks Jonathan Share.

- #1861: Added an attribute to the sched module which returns an ordered
  list of upcoming events (displayed as named tuples).

- #1837: The queue module now also supports a LIFO queue and a priority queue.

- Patch #1048820: Add insert-mode editing to curses.textpad.Textbox
  (patch by Stefan Wehr).  Also, fix an off-by-one bug in
  Textbox.gather().

- Issue #1831: ctypes now raises a TypeError if conflicting positional
  and named arguments are passed to a Structure or Union initializer.
  When too many positional arguments are passed, also a TypeError is
  raised instead of a ValueError.

- Convert the internal ctypes array type cache to a WeakValueDict so
  that array types do not live longer than needed.

- Issue #1786: pdb should use its own stdin/stdout around an exec call
  and when creating a recursive instance.

- Issue #1698398 Zipfile.printdir() crashed because the format string
  expected a tuple type of length six instead of time.struct_time object.

- Issue #1780: The Decimal constructor now accepts arbitrary leading
  and trailing whitespace when constructing from a string.
  Context.create_decimal no longer accepts trailing newlines.

- Decimal.as_tuple(), difflib.find_longest_match() and inspect functions
  that returned a tuple now return a named tuple.

- Doctest now returns results as a named tuple for readability:
      (0, 7) --> TestResults(failed=0, attempted=7)

- Issue #846388. re.match is interruptible now, which is particularly
  good for long regular expression matches.

- pyexpat, patch #1137: allow setting buffer_size attribute
  on Parser objects to set the character data buffer size.

- Issue #1757: The hash of a Decimal instance is no longer affected by
  the current context.

- Patch #467924: add ZipFile.extract() and ZipFile.extractall() in the
  zipfile module.

- Issue #1646: Make socket support the TIPC protocol.

- Bug #1742: return os.curdir from os.path.relpath() if both arguments are
  equal instead of raising an exception.

- Patch #1637: fix urlparse for URLs like 'http://x.com?arg=/foo'.

- Patch #1698: allow '@' in username parsed by urlparse.py.

- Issue #1735: TarFile.extractall() now correctly sets directory permissions
  and times.

- Bug #1713: posixpath.ismount() claims symlink to a mountpoint is a mountpoint.

- Bug #1687: Fxed plistlib.py restricts <integer> to Python int when writing

- Issue #1700: Regular expression inline flags incorrectly handle certain
  unicode characters.

- Issue #1689: PEP 3141, numeric abstract base classes.

- Tk issue #1851526: Return results from Python callbacks to Tcl as
  Tcl objects.

- Issue #1642: Fix segfault in ctypes when trying to delete attributes.

- Issue #1727780: Support loading pickles of random.Random objects created
  on 32-bit systems on 64-bit systems, and vice versa. As a consequence
  of the change, Random pickles created by Python 2.6 cannot be loaded
  in Python 2.5.

- Issue #1455: The distutils package now supports VS 2005 and VS 2008 for
  both the msvccompiler and cygwincompiler.

- Issue #1531: tarfile.py: Read fileobj from the current offset, do not
  seek to the start.

- Issue #1534: Added a dictionary sys.float_info with information about the
  internal floating point type to the sys module.

- Issue 1429818: patch for trace and doctest modules so they play nicely
  together.

- doctest made a bad assumption that a package's __loader__.get_data()
  method used universal newlines.

- Issue #1705170: contextlib.contextmanager was still swallowing
  StopIteration in some cases. This should no longer happen.

- Issue #1292: On alpha, arm, ppc, and s390 linux systems the
  --with-system-ffi configure option defaults to "yes".

- IN module for FreeBSD 8 is added and preexisting FreeBSD 6 and 7
  files are updated.

- Issues #1181, #1287: unsetenv() is now called when the os.environ.pop()
  and os.environ.clear() methods are used.

- ctypes will now work correctly on 32-bit systems when Python is
  configured with --with-system-ffi.

- Patch #1203: ctypes now does work on OS X when Python is built with
  --disable-toolbox-glue.

- collections.deque() now supports a "maxlen" argument.

- itertools.count() is no longer bounded to LONG_MAX.  Formerly, it raised
  an OverflowError.  Now, automatically shifts from ints to longs.

- Added itertools.product() which forms the Cartesian product of
  the input iterables.

- Patch #1541463: optimize performance of cgi.FieldStorage operations.

- Decimal is fully updated to the latest Decimal Specification (v1.66).

- Bug #1153: repr.repr() now doesn't require set and dictionary items
  to be orderable to properly represent them.

- A 'c_longdouble' type was added to the ctypes module.

- Bug #1709599: Run test_1565150 only if the file system is NTFS.

- When encountering a password-protected robots.txt file the RobotFileParser
  no longer prompts interactively for a username and password (bug 813986).

- TarFile.__init__() no longer fails if no name argument is passed and
  the fileobj argument has no usable name attribute (e.g. StringIO).

- The functools module now provides 'reduce', for forward compatibility
  with Python 3000.

- Server-side SSL support and cert verification added, by Bill Janssen.

- socket.ssl deprecated; use new ssl module instead.

- uuid creation is now threadsafe.

- EUC-KR codec now handles the cheot-ga-keut composed make-up hangul
  syllables.

- GB18030 codec now can encode additional two-byte characters that
  are missing in GBK.

- Add new codecs for UTF-32, UTF-32-LE and UTF-32-BE.

- Bug #1704793: Return UTF-16 pair if unicodedata.lookup cannot
  represent the result in a single character.

- Bug #978833: Close https sockets by releasing the _ssl object.

- Change location of the package index to pypi.python.org/pypi

- Bug #1701409: Fix a segfault in printing ctypes.c_char_p and
  ctypes.c_wchar_p when they point to an invalid location.  As a
  sideeffect the representation of these instances has changed.

- tarfile.py: Added "exclude" keyword argument to TarFile.add().

- Bug #1734723: Fix repr.Repr() so it doesn't ignore the maxtuple attribute.

- The urlopen function of urllib2 now has an optional timeout parameter (note
  that it actually works with HTTP, HTTPS, FTP and FTPS connections).

- In ftplib, the FTP.ntransfercmd method, when in passive mode, now uses
  the socket.create_connection function, using the timeout specified at
  connection time.

- Bug #1728403: Fix a bug that CJKCodecs StreamReader hangs when it
  reads a file that ends with incomplete sequence and sizehint argument
  for .read() is specified.

- Bug #1730389: Change time.strptime() to use ``\s+`` instead of ``\s*`` when
  matching spaces in the specified format argument.

- SF 1668596/1720897: distutils now copies data files
  even if package_dir is empty.

- sha now raises a DeprecationWarning upon import.

- md5 now raises a DeprecationWarning upon import.

- Issue1385: The hmac module now computes the correct hmac when using hashes
  with a block size other than 64 bytes (such as sha384 and sha512).

- mimify now raises a DeprecationWarning upon import.

- MimeWriter now raises a DeprecationWarning upon import.

- tarfile.py: Improved unicode support. Unicode input names are now
  officially supported. Added "errors" argument to the TarFile class.

- urllib.ftpwrapper class now accepts an optional timeout.

- shlex.split() now has an optional "posix" parameter.

- The posixfile module now raises a DeprecationWarning.

- Remove the gopherlib module.  This also leads to the removal of gopher
  support in urllib/urllib2.

- Fix bug in marshal where bad data would cause a segfault due to
  lack of an infinite recursion check.

- Removed plat-freebsd2 and plat-freebsd3 directories (and IN.py in
  the directories).

- HTML-escape the plain traceback in cgitb's HTML output, to prevent
  the traceback inadvertently or maliciously closing the comment and
  injecting HTML into the error page.

- The popen2 module and os.popen* are deprecated.  Use the subprocess module.

- Added an optional credentials argument to SMTPHandler, for use with SMTP
  servers which require authentication.

- Patch #1695948: Added optional timeout parameter to SocketHandler.

- Bug #1652788: Minor fix for currentframe.

- Patch #1598415: Added WatchedFileHandler to better support external
  log file rotation using e.g. newsyslog or logrotate. This handler is
  only useful in Unix/Linux environments.

- Bug #1706381: Specifying the SWIG option "-c++" in the setup.py file
  (as opposed to the command line) will now write file names ending in
  ".cpp" too.

- As specified in RFC 2616, an HTTP response like 2xx indicates that
  the client's request was successfully received, understood, and accepted.
  Now in these cases no error is raised in urllib (issue #1177) and urllib2.

- Bug #1290505: time.strptime's internal cache of locale information is now
  properly recreated when the locale is changed.

- Patch #1685563: remove (don't add) duplicate paths in distutils.MSVCCompiler.

- Added a timeout parameter to the constructor of other protocols
  (telnetlib, ftplib, smtplib and poplib). This is second part of the
  work started with create_connection() and timeout in httplib, and
  closes patch #723312.

- Patch #1676823: Added create_connection() to socket.py, which may be
  called with a timeout, and use it from httplib (whose HTTPConnection
  and HTTPSConnection now accept an optional timeout).

- Bug #978833: Revert r50844, as it broke _socketobject.dup.

- Bug #1675967: re patterns pickled with Python 2.4 and earlier can
  now be unpickled with Python 2.5 and newer.

- Patch #1630118: add a SpooledTemporaryFile class to tempfile.py.

- Patch #1273829: os.walk() now has a "followlinks" parameter. If set to
  True (which is not the default), it visits symlinks pointing to
  directories.

- Bug #1681228: the webbrowser module now correctly uses the default
  GNOME or KDE browser, depending on whether there is a session of one
  of those present. Also, it tries the Windows default browser before
  trying Mozilla variants.

- Patch #1339796: add a relpath() function to os.path.

- Patch #1681153: the wave module now closes a file object it opened if
  initialization failed.

- Bug #767111: fix long-standing bug in urllib which caused an
  AttributeError instead of an IOError when the server's response didn't
  contain a valid HTTP status line.

- Patch #957650: "%var%" environment variable references are now properly
  expanded in ntpath.expandvars(), also "~user" home directory references
  are recognized and handled on Windows.

- Patch #1429539: pdb now correctly initializes the __main__ module for
  the debugged script, which means that imports from __main__ work
  correctly now.

- The nonobvious commands.getstatus() function is now deprecated.

- Patch #1393667: pdb now has a "run" command which restarts the debugged
  Python program, optionally with different arguments.

- Patch #1649190: Adding support for _Bool to ctypes as c_bool.

- Patch #1530482: add pydoc.render_doc() which returns the documentation
  for a thing instead of paging it to stdout, which pydoc.doc() does.

- Patch #1533909: the timeit module now accepts callables in addition to
  strings for the code to time and the setup code. Also added two
  convenience functions for instantiating a Timer and calling its methods.

- Patch #1537850: tempfile.NamedTemporaryFile now has a "delete" parameter
  which can be set to False to prevent the default delete-on-close
  behavior.

- Patch #1581073: add a flag to textwrap that prevents the dropping of
  whitespace while wrapping.

- Patch #1603688: ConfigParser.SafeConfigParser now checks values that
  are set for invalid interpolation sequences that would lead to errors
  on reading back those values.

- Added support for the POSIX.1-2001 (pax) format to tarfile.py. Extended
  and cleaned up the test suite. Added a new testtar.tar.

- Patch #1449244: Support Unicode strings in
  email.message.Message.{set_charset,get_content_charset}.

- Patch #1542681: add entries for "with", "as" and "CONTEXTMANAGERS" to
  pydoc's help keywords.

- Patch #1555098: use str.join() instead of repeated string
  concatenation in robotparser.

- Patch #1635454: the csv.DictWriter class now includes the offending
  field names in its exception message if you try to write a record with
  a dictionary containing fields not in the CSV field names list.

- Patch #1668100: urllib2 now correctly raises URLError instead of
  OSError if accessing a local file via the file:// protocol fails.

- Patch #1677862: Require a space or tab after import in .pth files.

- Patch #1192590: Fix pdb's "ignore" and "condition" commands so they trap
  the IndexError caused by passing in an invalid breakpoint number.

- Patch #1599845: Add an option to disable the implicit calls to server_bind()
  and server_activate() in the constructors for TCPServer, SimpleXMLRPCServer
  and DocXMLRPCServer.

- Bug #1531963: Make SocketServer.TCPServer's server_address always
  be equal to calling getsockname() on the server's socket. Fixed by
  patch #1545011.

- Patch #742598: Add .timeout attribute to SocketServer that calls
  .handle_timeout() when no requests are received.

- Bug #1651235: When a tuple was passed to a ctypes function call,
  Python would crash instead of raising an error.

- Bug #1646630: ctypes.string_at(buf, 0) and ctypes.wstring_at(buf, 0)
  returned string up to the first NUL character.

- Patch #957003: Implement smtplib.LMTP.

- Patch #1481079: add support for HTTP_REFERER to CGIHTTPServer.

- Patch #1675424: Added tests for uncovered code in the zipfile module.
  The KeyError raised by Zipfile.getinfo for nonexistent names now has
  a descriptive message.

- Bug #1115886: os.path.splitext('.cshrc') gives now ('.cshrc', '').

- unittest now verifies more of its assumptions. In particular, TestCase
  and TestSuite subclasses (not instances) are no longer accepted in
  TestSuite.addTest(). This should cause no incompatibility since it
  never made sense with ordinary subclasses -- the failure just occurred
  later, with a more cumbersome exception.

- Patch #787789: allow to pass custom TestRunner instances to unittest's
  main() function.

- Patches #1550273, #1550272: fix a few bugs in unittest and add a
  comprehensive test suite for the module.

- Patch #1001604: glob.glob() now returns unicode filenames if it was
  given a unicode argument and os.listdir() returns unicode filenames.

- Patch #1673619: setup.py identifies extension modules it doesn't know how
  to build and those it knows how to build but that fail to build.

- Patch #912410: Replace HTML entity references for attribute values
  in HTMLParser.

- Patch #1663234: you can now run doctest on test files and modules
  using "python -m doctest [-v] filename ...".

- Patch #1121142: Implement ZipFile.open.

- Taught setup.py how to locate Berkeley DB on Macs using MacPorts.

- Added heapq.merge() for merging sorted input streams.

- Added collections.namedtuple() for assigning field names to tuples.

- Added itertools.izip_longest().

- Have the encoding package's search function dynamically import using absolute
  import semantics.

- Patch #1647484: Renamed GzipFile's filename attribute to name.

- Patch #1517891: Mode 'a' for ZipFile now creates the file if it
  doesn't exist.

- Patch #698833: Support file decryption in zipfile.

- Patch #685268: Consider a package's __path__ in imputil.

- Patch 1463026: Support default namespace in XMLGenerator.

- Patch 1571379: Make trace's --ignore-dir facility work in the face of
  relative directory names.

- Bug #1600860: Search for shared python library in LIBDIR,
  not lib/python/config, on "linux" and "gnu" systems.

- Patch #1652681: tarfile.py: create nonexistent files in append mode and
  allow appending to empty files.

- Bug #1124861: Automatically create pipes if GetStdHandle fails in
  subprocess.

- Patch #1634778: add missing encoding aliases for iso8859_15 and
  iso8859_16.

- Patch #1638243: the compiler package is now able to correctly compile
  a with statement; previously, executing code containing a with statement
  compiled by the compiler package crashed the interpreter.

- Bug #1643943: Fix time.strptime's support for the %U directive.

- Patch #1507247: tarfile.py: use current umask for intermediate
  directories.

- Patch #1627441: close sockets properly in urllib2.

- Bug #494589: make ntpath.expandvars behave according to its docstring.

- Changed platform module API python_version_tuple() to actually
  return a tuple (it used to return a list).

- Added new platform module APIs python_branch(), python_revision(),
  python_implementation() and linux_distribution().

- Added support for IronPython and Jython to the platform module.

- The sets module has been deprecated.  Use the built-in set/frozenset types
  instead.

- Bug #1610795: make ctypes.util.find_library work on BSD systems.

- Fixes for 64-bit Windows: In ctypes.wintypes, correct the
  definitions of HANDLE, WPARAM, LPARAM data types.  Make
  parameterless foreign function calls work.

- The version number of the ctypes package changed to "1.1.0".

- Bug #1627575: logging: Added _open() method to FileHandler which can
  be used to reopen files. The FileHandler instance now saves the
  encoding (which can be None) in an attribute called "encoding".

- Bug #411881: logging.handlers: bare except clause removed from
  SMTPHandler.emit. Now, only ImportError is trapped.

- Bug #411881: logging.handlers: bare except clause removed from
  SocketHandler.createSocket. Now, only socket.error is trapped.

- Bug #411881: logging: bare except clause removed from LogRecord.__init__.
  Now, only ValueError, TypeError and AttributeError are trapped.

- Patch #1504073: Fix tarfile.open() for mode "r" with a fileobj argument.

- Patch #1182394 from Shane Holloway: speed up HMAC.hexdigest.

- Patch #1262036: Prevent TarFiles from being added to themselves under
  certain conditions.

- Patch #1230446: tarfile.py: fix ExFileObject so that read() and tell()
  work correctly together with readline().

- Patch #1484695: The tarfile module now raises a HeaderError exception
  if a buffer given to frombuf() is invalid.

- Bug #1503765: Fix a problem in logging.config with spaces in comma-
  separated lists read from logging config files.

- Patch #1604907: Fix problems in logging.handlers caused at logging shutdown
  when syslog handlers fail to initialize because of syslogd problems.

- Patch #1608267: fix a race condition in os.makedirs() if the directory
  to be created is already there.

- Patch #1610437: fix a tarfile bug with long filename headers.

- Patch #1371075: Make ConfigParser accept optional dict type
  for ordering, sorting, etc.

- Bug #1563807: _ctypes built on AIX fails with ld ffi error.

- Bug #1598620: A ctypes Structure cannot contain itself.

- Patch #1070046: Marshal new-style objects like InstanceType
  in xmlrpclib.

- cStringIO.truncate(-1) now raises an IOError, like StringIO and
  regular files.

- Patch #1472877: Fix Tix subwidget name resolution.

- Patch #1594554: Always close a tkSimpleDialog on ok(), even
  if an exception occurs.

- Patch #1538878: Don't make tkSimpleDialog dialogs transient if
  the parent window is withdrawn.

- Bug #1597824: return the registered function from atexit.register()
  to facilitate usage as a decorator.

- Patch #1360200: Use unmangled_version RPM spec field to deal with
  file name mangling.

- Patch #1359217: Process 2xx response in an ftplib transfer
  that precedes an 1xx response.

- Patch #1355023: support whence argument for GzipFile.seek.

- Patch #1065257: Support passing open files as body in
  HTTPConnection.request().

- Bug #1569790: mailbox.py: Maildir.get_folder() and MH.get_folder()
  weren't passing the message factory on to newly created Maildir/MH
  objects.

- Patch #1514543: mailbox.py: In the Maildir class, report errors if there's
  a filename clash instead of possibly losing a message.  (Patch by David
  Watson.)

- Patch #1514544: Try to ensure that messages/indexes have been physically
  written to disk after calling .flush() or .close(). (Patch by David
  Watson.)

- Patch #1592250: Add elide argument to Tkinter.Text.search.

- Patch #838546: Make terminal become controlling in pty.fork().

- Patch #1351744: Add askyesnocancel helper for tkMessageBox.

- Patch #1060577: Extract list of RPM files from spec file in
  bdist_rpm.

- Bug #1586613: fix zlib and bz2 codecs' incremental en/decoders.

- Patch #1583880: fix tarfile's problems with long names and posix/
  GNU modes.

- Bug #1586448: the compiler module now emits the same bytecode for
  list comprehensions as the builtin compiler, using the LIST_APPEND
  opcode.

- Fix codecs.EncodedFile which did not use file_encoding in 2.5.0, and
  fix all codecs file wrappers to work correctly with the "with"
  statement (bug #1586513).

- Lib/modulefinder.py now handles absolute and relative imports
  correctly.

- Patch #1567274: Support SMTP over TLS.

- Patch #1560695: Add .note.GNU-stack to ctypes' sysv.S so that
  ctypes isn't considered as requiring executable stacks.

- ctypes callback functions only support 'fundamental' data types as
  result type.  Raise an error when something else is used.  This is a
  partial fix for Bug #1574584.

- Fix turtle so that time.sleep is imported for the entire library.  Allows
  the demo2 function to be executed on its own instead of only when the
  module is run as a script.

- Bug #813342: Start the IDLE subprocess with -Qnew if the parent
  is started with that option.

- Bug #1565150: Fix subsecond processing for os.utime on Windows.

- Support for MSVC 8 was added to bdist_wininst.

- Bug #1446043: correctly raise a LookupError if an encoding name given
  to encodings.search_function() contains a dot.

- Bug #1560617: in pyclbr, return full module name not only for classes,
  but also for functions.

- Bug #1457823: cgi.(Sv)FormContentDict's constructor now takes
  keep_blank_values and strict_parsing keyword arguments.

- Bug #1566602: correct failure of posixpath unittest when $HOME ends
  with a slash.

- Bug #1565661: in webbrowser, split() the command for the default
  GNOME browser in case it is a command with args.

- Made the error message for time.strptime when the data data and format do
  match be more clear.

- Fix a bug in traceback.format_exception_only() that led to an error
  being raised when print_exc() was called without an exception set.
  In version 2.4, this printed "None", restored that behavior.

- Make webbrowser.BackgroundBrowser usable in Windows (it wasn't because
  the close_fds arg to subprocess.Popen is not supported).

- Reverted patch #1504333 to sgmllib because it introduced an infinite loop.

- Patch #1553314: Fix the inspect.py slowdown that was hurting IPython & SAGE
  by adding smarter caching in inspect.getmodule()

- Fix missing import of the types module in logging.config.

- Patch #1550886: Fix decimal module context management implementation
  to match the localcontext() example from PEP 343.

- Bug #1545341: The 'classifier' keyword argument to the Distutils setup()
  function now accepts tuples as well as lists.

- Bug #1541863: uuid.uuid1 failed to generate unique identifiers
  on systems with low clock resolution.

- Bug #1531862: Do not close standard file descriptors in subprocess.

- idle: Honor the "Cancel" action in the save dialog (Debian bug #299092).

- Fix utf-8-sig incremental decoder, which didn't recognise a BOM when the
  first chunk fed to the decoder started with a BOM, but was longer than 3
  bytes.

- The implementation of UnicodeError objects has been simplified (start and end
  attributes are now stored directly as Py_ssize_t members).

- Issue829951: In the smtplib module, SMTP.starttls() now complies with
  RFC 3207 and forgets any knowledge obtained from the server not obtained
  from the TLS negotiation itself.  Patch contributed by Bill Fenner.

- Issue1339: The smtplib.SMTP class has been refactored a bit such
  that the SMTP.starttls() caller no longer needs to call ehlo()
  beforehand.  SMTP.starttls() now raises an exception of the server
  does not claim to support starttls.  Adds the SMTP.ehlo_or_helo_if_needed()
  method.  Patch contributed by Bill Fenner.


Extension Modules
-----------------

- #2112: mmap.error is now a subclass of EnvironmentError and not a
  direct EnvironmentError

- Bug #2111: mmap segfaults when trying to write a block opened with PROT_READ

- #2063: correct order of utime and stime in os.times() result on Windows.

- Patch #1736: Fix file name handling of _msi.FCICreate.

- Updated ``big5hkscs`` codec to the HKSCS revision of 2004.

- #1940: make it possible to use curses.filter() before curses.initscr()
  as the documentation says.

- Backport of _fileio module from Python 3.0.

- #1087741: mmap.mmap is now a class, not a factory function. It is also
  subclassable now.

- Patch #1648: added ``sys.getprofile()`` and ``sys.gettrace()``.

- Patch #1663329: added ``os.closerange()`` function to quickly close a range
  of file descriptors without considering errors.

- Patch 976880: ``mmap`` objects now have an ``rfind`` method that
  works as expected.  ``mmap.find`` also takes an optional ``end``
  parameter.

- _winreg's HKEY object has gained __enter__ and __exit__ methods to support
  the context manager protocol.  The _winreg module also gained a new function
  ``ExpandEnvironmentStrings`` to expand REG_EXPAND_SZ keys.

- itertools.starmap() now accepts any iterable input. Previously, it required
  the function inputs to be tuples.

- Issue #1646: Make socket support TIPC. The socket module now has support
  for TIPC under Linux, see http://tipc.sf.net/ for more information.

- Added interface for Windows' WSAIoctl to socket object and added an example
  for a simple network sniffer.

- Bug #1301: Bad assert in _tkinter fixed.

- Added bdist_wininst executable for VS 2008.

- Bug #1604: collections.deque.__init__(iterable) now clears any prior contents
  before adding elements from the iterable.  This fix brings the behavior into
  line with that for list.__init__().

- Added wide char functions to msvcrt module: getwch, getwche, putwch and
  ungetwch. The functions accept or return unicode.

- os.access now returns True on Windows for any existing directory.

- Added warnpy3k function to the warnings module.

- Marshal.dumps() now expects exact type matches for int, long, float, complex,
  tuple, list, dict, set, and frozenset.  Formerly, it would silently miscode
  subclasses of those types.  Now, it raises a ValueError instead.

- Patch #1388440: Add set_completion_display_matches_hook and
  get_completion_type to readline.

- Bug #1649098: Avoid declaration of zero-sized array declaration in
  structure.

- Removed the rgbimg module; been deprecated since Python 2.5.

- Bug #1721309: prevent bsddb module from freeing random memory.

- Bug #1233: fix bsddb.dbshelve.DBShelf append method to work as
  intended for RECNO databases.

- pybsddb.sf.net Bug #477182: Load the database flags at database open
  time so that opening a database previously created with the DB_DUP or
  DB_DUPSORT flag set will keep the proper behavior on subsequent opens.
  Specifically: dictionary assignment to a DB object will replace all
  values for a given key when the database allows duplicate values.
  DB users should use DB.put(k, v) when they want to store duplicates; not
  DB[k] = v.

- Add the bsddb.db.DBEnv.lock_id_free method.

- Bug #1686475: Support stat'ing open files on Windows again.

- Patch #1185447: binascii.b2a_qp() now correctly quotes binary characters
  with ASCII value less than 32. Also, it correctly quotes dots only if
  they occur on a single line, as opposed to the previous behavior of
  quoting dots if they are the second character of any line.

- Bug #1622896: fix a rare corner case where the bz2 module raised an
  error in spite of a succesful compression.

- Patch #1654417: make operator.{get,set,del}slice use the full range
  of Py_ssize_t.

- Patch #1646728: datetime.fromtimestamp fails with negative
  fractional times.  With unittest.

- Patch #1490190: posixmodule now includes os.chflags() and os.lchflags()
  functions on platforms where the underlying system calls are available.

- Patch #1494140: Add documentation for the new struct.Struct object.

- Patch #1432399: Support the HCI protocol for bluetooth sockets

- Patch #1657276: Make NETLINK_DNRTMSG conditional.

- Bug #1653736: Complain about keyword arguments to time.isoformat.

- Bug #1486663: don't reject keyword arguments for subclasses of builtin
  types.

- Patch #1610575: The struct module now supports the 't' code, for
  C99 _Bool.

- Patch #1635058: ensure that htonl and friends never accept or
  return negative numbers, per the underlying C implementation.

- Patch #1544279: Improve thread-safety of the socket module by moving
  the sock_addr_t storage out of the socket object.

- Patch #1019808: fix bug that causes an incorrect error to be returned
  when a socket timeout is set and a connection attempt fails.

- Speed up function calls into the math module.

- Bug #1588217: don't parse "= " as a soft line break in binascii's
  a2b_qp() function, instead leave it in the string as quopri.decode()
  does.

- Bug #1599782: Fix segfault on bsddb.db.DB().type().

- Bug #1567666: Emulate GetFileAttributesExA for Win95.

- Patch #1576166: Support os.utime for directories on Windows NT+.

- Patch #1572724: fix typo ('=' instead of '==') in _msi.c.

- Bug #1572832: fix a bug in ISO-2022 codecs which may cause segfault
  when encoding non-BMP unicode characters.

- Bug #1556784: allow format strings longer than 127 characters in
  datetime's strftime function.

- Fix itertools.count(n) to work with negative numbers again.

- RLIMIT_SBSIZE was added to the resource module where available.

- Bug #1551427: fix a wrong NULL pointer check in the win32 version
  of os.urandom().

- Bug #1548092: fix curses.tparm seg fault on invalid input.

- Patch #1114: fix curses module compilation on 64-bit AIX, & possibly
  other 64-bit LP64 platforms where attr_t is not the same size as a long.
  (Contributed by Luke Mewburn.)

- Bug #1550714: fix SystemError from itertools.tee on negative value for n.

- Fixed a few bugs on cjkcodecs:
  - gbk and gb18030 codec now handle U+30FB KATAKANA MIDDLE DOT correctly.
  - iso2022_jp_2 codec now encodes into G0 for KS X 1001, GB2312
    codepoints to conform the standard.
  - iso2022_jp_3 and iso2022_jp_2004 codec can encode JIS X 0213:2
    codepoints now.

- Bug #1552726: in readline.c, avoid repeatedly polling in interactive
  mode by only placing a timeout on the select() if an input hook has
  been defined.  This prevents an interactive Python from waking up 10
  times per second.  Patch by Richard Boulton.

- fixed a bug with bsddb.DB.stat: the flags and txn keyword arguments
  were transposed.

- Added support for linking the bsddb module against BerkeleyDB 4.5.x
  and 4.6.x.

- Bug #1633621: if curses.resizeterm() or curses.resize_term() is called,
  update _curses.LINES, _curses.COLS, curses.LINES and curses.COLS.

- Fix an off-by-one bug in locale.strxfrm().

- Fix libffi configure for hppa*-*-linux* | parisc*-*-linux*.

- Build using system ffi library on arm*-linux*.

- Bug #1372: zlibmodule.c: int overflow in PyZlib_decompress

- bsddb module: Fix memory leak when using database cursors on
  databases without a DBEnv.

Tests
-----

- Refactor test_logging to use doctest.

- Refactor test_profile and test_cprofile to use the same code to profile.

- Make test_runpy reentrant by fixing _check_module to clear out any module
  being tested.  Was causing an error by __import__ doing a reload on the
  second run and thus suppressing bytecode recreation.

- Capture socket connection resets and timeouts in test_socket_ssl and
  test_urllib2net and raise test.test_support.ResourceDenied.

- Patch #1559413: Fix test_cmd_line if sys.executable contains a space.

- Added test.test_support.TransientResource which is a context manager to
  surround calls to resources that are not guaranteed to work even if
  test.test_support.requires says that the resource should exist.

- Added a test for slicing of an exception.

- Added test.test_support.EnvironmentVarGuard.  It's a class that provides a
  context manager so that one can temporarily set or unset environment
  variables.

- Added some tests for modulefinder.

- Converted test_imp to use unittest.

- Fix bsddb test_basics.test06_Transactions to check the version
  number properly.

- test.test_support.catch_warning is a new context manager that can be used
  to catch the warnings issued by the warning framework.


Tools
-----

- Tools/scripts/reindent.py now creates the backup file using shutil.copy
  to preserve user/group and permissions. Added also a --nobackup option
  to not create the backup if the user is concerned regarding this.  Check
  issue 1050828 for more details.

- Tools/scripts/win_add2path.py was added. The simple script modifes the
  PATH environment var of the HKCU tree and adds the python bin and script
  directory.

- Tools/18n/pygettext.py was added to the list of scripts installed by
  Tools/scripts/setup.py (tracker item 642309).

- Added IronPython and Jython support to pybench (part of which
  was patch #1563844)

- Made some minor changes to pybench output to allow the user
  to see which Python version is running pybench

- Added support for the new platform module feature
  platform.python_implementation(); this will now be saved
  in the benchmark pickle


Documentation
-------------

- RFE #1765140: Updated documentation on FileHandler and subclasses to
  include new optional delay argument.

- Bug #932563: Added section on getting contextual information into logging
  output, and added documentation for the new LoggerAdapter class.

- Bug #1295: Added information about caching of formatted exception
  information in the LogRecord by Formatter.format().

- Bug #1637365: add subsection about "__name__ == __main__" to the
  Python tutorial.

- Patch #1698768: updated the "using Python on the Mac" intro.

- Bug #1569057: Document that calling file.next() when the file is open for
  writing is undefined.

- Patch #1489771: the syntax rules in Python Reference Manual were
  updated to reflect the current Python syntax.

- Patch #1686451: Fix return type for
  PySequence_{Count,Index,Fast_GET_SIZE}.

- Patch #1679379: add documentation for fnmatch.translate().

- Bug #1629566: clarify the docs on the return values of parsedate()
  and parsedate_tz() in email.utils and rfc822.

- Patch #1671450: add a section about subclassing builtin types to the
  "extending and embedding" tutorial.

- Bug #1629125: fix wrong data type (int -> Py_ssize_t) in PyDict_Next
  docs.

- Bug #1565919: document set types in the Language Reference.

- Bug #1546052: clarify that PyString_FromString(AndSize) copies the
  string pointed to by its parameter.

- Bug #1566663: remove obsolete example from datetime docs.

- Bug #1541682: Fix example in the "Refcount details" API docs.
  Additionally, remove a faulty example showing PySequence_SetItem applied
  to a newly created list object and add notes that this isn't a good idea.


Tools/Demos
-----------

- Patch #1552024: add decorator support to unparse.py demo script.

- Make auto-generated python.vim file list built-ins and exceptions in
  alphatbetical order.  Makes output more deterministic and easier to tell if
  the file is stale or not.

- Bug #1546372: Fixed small bugglet in pybench that caused a missing
  file not to get reported properly.


Build
-----

- Have the search path for building extensions follow the declared order in
  $CPPFLAGS and $LDFLAGS when adding directories from those environment
  variables.

- Bug #1983: Added a check to pyport to verify that sizeof(pid_t) is
  smaller or equal sizeof(long).

- Bug #1234: Fixed semaphore errors on AIX 5.2

- Issue #1726: Remove Python/atof.c from PCBuild/pythoncore.vcproj

- Removed PCbuild8/ directory and added a new build directory for VS 2005
  based on the VS 2008 build directory to PC/VS8.0. The script
  PCbuild/vs8to9.py was added to sync changes from PCbuild to PC/VS8.0.

- Moved PCbuild/ directory for VS 2003 to PC/VS7.1 and renamed PCBuild9/
  directory to PCBuild/.

- Bug #1699: Define _BSD_SOURCE only on OpenBSD.

- Bug #1608: use -fwrapv when GCC supports it.  This is important,
  newer GCC versions may optimize away overflow buffer overflow checks
  without this option!

- Patch #1418: Make the AC_REPLACE_FUNCS object files actually work.

- Add a FAST_LOOPS build option that speeds-up looping by trading away
  periodic threadstate and signal checking in tight loops.  By default,
  this option is turned-off.  It should only be enabled in debugged,
  performance critical applications.

- Patch #786737: Allow building in a tree of symlinks pointing to
  a readonly source.

- Bug #1737210: Change Manufacturer of Windows installer to PSF.

- Bug #1746880: Correctly install DLLs into system32 folder on Win64.

- Define _BSD_SOURCE, to get access to POSIX extensions on OpenBSD 4.1+.

- Stop supporting AtheOS and cause a build error in configure for the platform.

- Bug #1655392: don't add -L/usr/lib/pythonX.Y/config to the LDFLAGS
  returned by python-config if Python was built with --enable-shared
  because that prevented the shared library from being used.

- Patch #1569798: fix a bug in distutils when building Python from a
  directory within sys.exec_prefix.

- Bug #1675511: Use -Kpic instead of -xcode=pic32 on Solaris/x86.

- Disable _XOPEN_SOURCE on NetBSD 1.x.

- configure now checks whether gcc supports the PyArg_ParseTuple format
  attribute.

- Bug #1578513: Cross compilation was broken by a change to configure.
  Repair so that it's back to how it was in 2.4.3.

- Patch #1576954: Update VC6 build directory; remove redundant
  files in VC7.

- Bug #1568842: Fix test for uintptr_t.

- Patch #1540470, for OpenBSD 4.0.

- Fix build failure on kfreebsd and on the hurd.

- Fix the build of the library reference in info format.

- Allow Emacs 22 for building the documentation in info format.

- Makefile.pre.in(buildbottest): Run an optional script pybuildbot.identify
  to include some information about the build environment.


C API
-----

- Unified naming convention for free lists and their limits. All free lists
  in Object/ are named ``free_list``, the counter ``numfree`` and the upper
  limit is a macro ``PyName_MAXFREELIST`` inside an #ifndef block.

- ``PySet_Add()`` can now modify a newly created frozenset.  Similarly to
  ``PyTuple_SetItem``, it can be used to populate a brand new frozenset; but 
  it does not steal a reference to the added item.

- Added ``PySet_Check()`` and ``PyFrozenSet_Check()`` to the set API. 

- Backport of PyUnicode_FromString(), _FromStringAndSize(), _Format and
  _FormatV from Python 3.0. Made PyLong_AsSsize_t and PyLong_FromSsize_t
  public functions.

- Patch #1720595: add T_BOOL to the range of structmember types.

- Issue #1534: Added ``PyFloat_GetMax()``, ``PyFloat_GetMin()`` and
  ``PyFloat_GetInfo()`` to the float API.

- Issue #1521: On 64bit platforms, using PyArgs_ParseTuple with the t# of w#
  format code incorrectly truncated the length to an int, even when
  PY_SSIZE_T_CLEAN is set.  The str.decode method used to return incorrect
  results with huge strings.

- Issue #1629: Renamed Py_Size, Py_Type and Py_Refcnt to Py_SIZE, Py_TYPE
  and Py_REFCNT.

- PEP 3123: Provide forward compatibility with Python 3.0, while keeping
  backwards compatibility. Add Py_Refcnt, Py_Type, Py_Size, and
  PyVarObject_HEAD_INIT.

- Py_ssize_t fields work in structmember when HAVE_LONG_LONG is not defined.

- Patch #1733960: Allow T_LONGLONG to accept ints.

- T_PYSSIZET can now be used in PyMemberDef lists for Py_ssize_t members.

- Added a new API function ``PyImport_ImportModuleNoBlock``.

- Bug #1637022: Prefix AST symbols with _Py_.

- Fix some leftovers from the conversion from int to Py_ssize_t
  (relevant to strings and sequences of more than 2**31 items).

- Make _PyGILState_NoteThreadState() static, it was not used anywhere
  outside of pystate.c and should not be necessary.

- ``PyImport_Import`` and ``PyImport_ImportModule`` now always do absolute
  imports. In earlier versions they might have used relative imports under
  some conditions.

- Added case insensitive comparison methods ``PyOS_stricmp(char*, char*)``
  and ``PyOS_strnicmp(char*, char*, Py_ssize_t)``.

- Bug #1542693: remove semi-colon at end of PyImport_ImportModuleEx macro
  so it can be used as an expression.


Windows
-------

- Patch #1706: Drop support for Win9x, WinME and NT4. Python now requires 
  Windows 2000 or greater. The _WINVER and NTDDI_VERSION macros are set to
  Win2k for x86/32bit builds and WinXP for AMD64 builds.

- Conditionalize definition of _CRT_SECURE_NO_DEPRECATE
  and _CRT_NONSTDC_NO_DEPRECATE.

- Bug #1216: Restore support for Visual Studio 2002.


Mac
---

- cfmfile now raises a DeprecationWarning.

- buildtools now raises a DeprecationWarning.

- Removed the macfs module.  It had been deprecated since Python 2.5.  This
  lead to the deprecation of macostools.touched() as it relied solely on macfs
  and was a no-op under OS X.

----

**(For information about older versions, consult the HISTORY file.)**