Fix and initial test patch by Michele Orrù.

Issue #12168: SysLogHandler now allows NUL termination to be controlled using a new 'append_nul' attribute on the handler.

Rather than wrapping the C _isdir function in a Python function,
just import the C _isdir function directly. Additionally, add in the
docstring which was left out.

The example C extension used the “three.fast_taunt” name, but no “three” parent
was defined in the setup.cfg.  This did not cause a failure nor even print a
warning, we may want to change that.

By changing to the Windows GetFileAttributes API in nt._isdir we can figure
out if the path is a directory without opening the file via os.stat. This has
the minor benefit of speeding up os.path.isdir by at least 2x for regular
files and 10-15x improvements were seen on symbolic links (which opened the
file multiple times during os.stat). Since os.path.isdir is used in
several places on interpreter startup, we get a minor speedup in startup time.

By changing to the Windows GetFileAttributes API in nt._isdir we can figure
out if the path is a directory without opening the file via os.stat. This has
the minor benefit of speeding up os.path.isdir by at least 2x for regular
files and 10-15x improvements were seen on symbolic links (which opened the
file multiple times during os.stat). Since os.path.isdir is used in
several places on interpreter startup, we get a minor speedup in startup time.

Lehtinen.

children and raises BrokenProcessPool in such a situation.  Previously it
would reliably freeze/deadlock.

Extract of the commit message:

  Fix usage of :option: in the docs (#9312).

  :option: is used to create a link to an option of python, not to mark
  up any instance of any arbitrary command-line option.  These were
  changed to ````.

Such tests are IMO easier to read if both operators are grouped.

This helps debugging in case of trailing blanks and such things.

Namely: use default arguments instead of explicit empty string; use multiple
arguments instead of building strings.

temporary symbolic link.

Found by LLVM/clang 2.9.

Found by LLVM/clang 2.9.

prevent accidental assignment.

Silences a warning from LLVM/clang 2.9.

always appended to the include directories regardless of whether it
was already in the list of directories. This could cause issue if
sqlite was installed in the same location as another install of
Python. Now a check is done to make sure the directory is not included
twice.

instead of an active loop (while True: pass) to limit race conditions.