warning on Windows.

Afraid I can't detect a pattern to when the pack formats decide
to use a signed or unsigned format code -- appears nearly
arbitrary to my eyes.  So I left all the pack formats alone and
changed the special-case data values instead.

warnings on Win32.

Also added an XXX about the line:

                pos3 = self.fp.tell()

`pos3` is never referenced, and I have no idea what the code
intended to do instead.

and may need to be reverted if it causes problems.

Fixes #1439538
Will backport to 2.4
Also regenerate pyconfig.h.in.

Fixes #1257728.

no longer maintained separatedly.

Fixes #1525866.

refers to file descriptors, not file objects.

Pass the char* and size around rather than PyObject's.

This provides the proper warning for struct.pack().
PyErr_Warn() is now deprecated in favor of PyErr_WarnEx().
As mentioned by Tim Peters on python-dev.

Also fix a SystemError when trying to assign to yield expressions.

- fix an internal section reference

it is hard to know whether this is right, and it does not add valuable reference information
at any rate

This prevents garbage about command not found being printed on Solaris.

treatment of newlines changed in 2.5.  Pulled almost verbatim from a comment
by Andrew McNamara in <http://python.org/sf/1465014>.

The information about supporting weakrefs with types defined in C extensions
is moved to the Extending & Embedding manual.  Py_TPFLAGS_HAVE_WEAKREFS is
no longer mentioned since it is part of Py_TPFLAGS_DEFAULT.

[Patch #1068277] Clarify that os.path.exists() can return False depending on permissions.  Fred approved committing this patch in December 2004!

These problems may mask more important, real problems.

One or both methods are known to fail on: Solaris, OpenBSD, Debian, Ubuntu.
They pass on Windows and some Linux boxes.

[Patch #1490989 from Skip Montanaro]  Mention debugging builds in the API documentation.  I've changed Skip's patch to point to Misc/SpecialBuilds and fiddled with the markup a bit.