[0xrutabaga]

Fixes #375.

Problem

On Windows, \os.getpgid\ and \os.killpg\ are not implemented. During hard timeout in \TimeoutHandler._trywaitkill(process), calling \os.getpgid(worker.pid) == worker.pid\ raises \AttributeError: module 'os' has no attribute 'getpgid', crashing the \TimeoutHandler\ thread.

Solution

• Check \hasattr(os, 'getpgid')\ and \hasattr(os, 'killpg')\ before calling \os.getpgid\ and \os.killpg.
• On platforms lacking these functions (such as Windows), fall back directly to \worker.terminate()\ and _kill(worker.pid, SIGKILL)\ (which invokes \kill_processtree\ on Windows).
• Add unit tests verifying \TimeoutHandler._trywaitkill\ gracefully handles platforms lacking \os.getpgid\ / \os.killpg.

Verification

• Verified \ /unit/test_pool.py::test_pool::test_hard_timeout_does_not_stall_pool\ passes on Windows without thread crash (previously failed with \AttributeError).
• Added unit tests in \ /unit/test_pool.py\ testing _trywaitkill\ when \os.getpgid\ and \os.killpg\ are absent.

[auvipy]

got this from the issue comment:

I believe if the OS is Windows then you should skip the first if statement and go directly to the else. Windows does not support getpgid.

Adding a sys.platform != "win32" as the first check in line 702 and 713 seems to fix the issue.

[0xrutabaga]

Thank you for the review and suggestion @auvipy!

I have updated the PR to explicitly check sys.platform != 'win32' as the first guard in both the SIGTERM and SIGKILL escalation branches in TimeoutHandler._trywaitkill, while retaining the hasattr checks so non-Windows environments lacking process-group capabilities remain protected.

In addition, I expanded the unit test suite in /unit/test_pool.py to cover:

• Windows platform termination and escalation to _kill(worker.pid, SIGKILL)
• POSIX process-group leader kill (os.killpg for both SIGTERM and SIGKILL)
• POSIX non-group leader fallback to worker.terminate()
• Fallback when os.getpgid or os.killpg are missing on non-Windows platforms
• OSError handling and suppression during termination races

All unit tests pass on Windows (119 passed, 15 skipped).