tests.

Will backport to release25-maint.

not the posix error code; with test.
Fixes #1576174.

Will backport to release25-maint.

base64.encodestring() for encoding authentication data.
encodestring() can include newlines for very long input, which
produced broken HTTP headers.

[Bug #1575506] The _singlefileMailbox class was using the wrong file object in its flush() method, causing an error

Point users to the subprocess module in the docs for os.system, os.spawn*, os.popen2, and the popen2 and commands modules

[Bug #1542016] Report PCALL_POP value.  This makes the return value of sys.callstats() match its docstring.

Backport candidate.  Though it's an API change, this is a pretty obscure
portion of the API.

Fixes #1545696 and #1566140. Will backport to 2.5.

for test_nis. Will backport to 2.5.

  ctypes isn't considered as requiring executable stacks.
Will backport to 2.5.

Will backport to 2.5.

decode unicode objects and returns an unicode object when the argument is one.

PyArg_ParseTuple.

it if it is supported.

Check this and raise an error when something else is used - before
this change ctypes would hang or crash when such a callback was
called.  This is a partial fix for #1574584.

Will backport to release25-maint.

- 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.