gh-102141: replace use of getpid on Windows with GetCurrentProcessId

[maxbachmann]

• Issue: replace use of getpid on Windows with GetCurrentProcessId #102141

[eryksun]

My opinion may be in the minority here, but I'd prefer to not define HAVE_GETPID in "PC/pyconfig.h" if we're not actually using getpid().

cpython/PC/pyconfig.h

Lines 509 to 510 in 7c106a4

	/* Define if you have getpid. */
	#define HAVE_GETPID

I know other cases have defined a POSIX system function as being available on Windows that isn't actually available (e.g. HAVE_GETPPID and getppid()), or never gets used or shouldn't be used. That seems like a quick and dirty approach that may eventually cause a regression. I'd prefer to explicitly check for Windows in the cases where we use the Windows API directly or have our own implementation with a different name. For example, #if defined(HAVE_GETPID) || defined(MS_WINDOWS).

[maxbachmann]

One difference with e.g. HAVE_GETPPID is that it is at least a hack that is local to the posixmodule.

[ghost]

All commit authors signed the Contributor License Agreement.

[zooba]

My opinion may be in the minority here, but I'd prefer to not define HAVE_GETPID in "PC/pyconfig.h" if we're not actually using getpid().

We can both be in the minority then. I'm sure I've done it in the past, but have definitely come around to it not being a great idea (I'm still tempted to split the Windows definitions into ntmodule.c, which would actually make things neater).

[zooba]

Great, thanks for being responsive! And thanks for the patch

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot ARM64 macOS 3.x has failed when building commit 1fa3890.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/all/#builders/725/builds/3804) and take a look at the build logs.
4. Check if the failure is related to this commit (1fa3890) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/all/#builders/725/builds/3804

Failed tests:

• test_asyncio

Failed subtests:

• test_wait_for_race_condition - test.test_asyncio.test_waitfor.AsyncioWaitForTest.test_wait_for_race_condition

Summary of the results of the build (if available):

== Tests result: FAILURE then FAILURE ==

405 tests OK.

10 slowest tests:

• test_signal: 4 min 21 sec
• test_concurrent_futures: 2 min 39 sec
• test_multiprocessing_spawn: 2 min 4 sec
• test_ssl: 1 min 45 sec
• test_multiprocessing_forkserver: 1 min 36 sec
• test_asyncio: 1 min 28 sec
• test_logging: 1 min 10 sec
• test_math: 1 min 9 sec
• test_capi: 46.9 sec
• test_io: 38.7 sec

1 test failed:
test_asyncio

25 tests skipped:
test_check_c_globals test_devpoll test_epoll test_gdb test_idle
test_ioctl test_launcher test_msilib test_multiprocessing_fork
test_ossaudiodev test_peg_generator test_perf_profiler test_spwd
test_startfile test_tcl test_tix test_tkinter test_ttk
test_ttk_textonly test_turtle test_winconsoleio test_winreg
test_winsound test_wmi test_zipfile64

1 re-run test:
test_asyncio

Total duration: 9 min

Click to see traceback logs

Traceback (most recent call last):
  File "/Users/buildbot/buildarea/3.x.pablogsal-macos-m1.macos-with-brew/build/Lib/asyncio/tasks.py", line 478, in wait_for
    return await fut
           ^^^^^^^^^
asyncio.exceptions.CancelledError


Traceback (most recent call last):
  File "/Users/buildbot/buildarea/3.x.pablogsal-macos-m1.macos-with-brew/build/Lib/unittest/async_case.py", line 90, in _callTestMethod
    if self._callMaybeAsync(method) is not None:
       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/buildbot/buildarea/3.x.pablogsal-macos-m1.macos-with-brew/build/Lib/unittest/async_case.py", line 112, in _callMaybeAsync
    return self._asyncioRunner.run(
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/buildbot/buildarea/3.x.pablogsal-macos-m1.macos-with-brew/build/Lib/asyncio/runners.py", line 118, in run
    return self._loop.run_until_complete(task)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/buildbot/buildarea/3.x.pablogsal-macos-m1.macos-with-brew/build/Lib/asyncio/base_events.py", line 664, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "/Users/buildbot/buildarea/3.x.pablogsal-macos-m1.macos-with-brew/build/Lib/test/test_asyncio/test_waitfor.py", line 163, in test_wait_for_race_condition
    res = await task
          ^^^^^^^^^^
  File "/Users/buildbot/buildarea/3.x.pablogsal-macos-m1.macos-with-brew/build/Lib/asyncio/tasks.py", line 477, in wait_for
    async with timeouts.timeout(timeout):
  File "/Users/buildbot/buildarea/3.x.pablogsal-macos-m1.macos-with-brew/build/Lib/asyncio/timeouts.py", line 98, in __aexit__
    raise TimeoutError
TimeoutError