Hi,

time.sleep() function is not working on Windows host if I use C API Py_InitializeEx(0) function.

Issue could be reproduce with following simple example.

int main()
{
   Py_InitializeEx(0);
   PyRun_SimpleString("import time \n"
		      "start = time.time() \n"
		      "time.sleep(4) \n"
		      "print('elapsed: %d' % (time.time() - start))");
}

output:

elapsed: 0

Note, issue is not reproduce on Linux host.

The SIGINT event gets created when the _signal extension module is imported. Until then, _PyOS_SigintEvent() returns NULL. But currently all code that calls _PyOS_SigintEvent() assumes it returns a valid handle. This has to be fixed to support Py_InitializeEx(0).

For example, pysleep could call WinAPI Sleep on the main thread if the interrupt event isn't configured:

        ul_millis = (unsigned long)millisecs;
        hInterruptEvent = _PyOS_SigintEvent();

        if (ul_millis == 0 || !hInterruptEvent || !_PyOS_IsMainThread()) {
            Py_BEGIN_ALLOW_THREADS
            Sleep(ul_millis);
            Py_END_ALLOW_THREADS
            break;
        }

Py_InitializeEx() should be modified to always initialize sigint_event, even if install_sigs is equal to zero.

Maybe the variable should be moved somewhere else. Maybe in the time module?

By the way, it would be nice to add error handling on:

    sigint_event = CreateEvent(NULL, TRUE, FALSE, FALSE);

See also PR bpo-22049.

Maybe in the time module?

The SIGINT event is also needed by PyOS_Readline, _io (builtin), _winapi (builtin), and _multiprocessing (pyd). Is the time module guaranteed to be imported in 3.x? It appears to get imported incidentally via _PyImportZip_Init (zipimport).

Could sigint_event be relocated to a platform-dependent extension of _PyRuntimeState that gets initialized and finalized independent of any module?

Could sigint_event be relocated to a platform-dependent extension of _PyRuntimeState that gets initialized and finalized independent of any module?

This, or leaving it where it is and making sure it gets initialised (it really is about emulating certain signals). Either sounds fine to me.

New changeset 0ae323b by Victor Stinner in branch 'master':
bpo-41686: Always create the SIGINT event on Windows (GH-23344)
0ae323b

New changeset cda23be by Victor Stinner in branch 'master':
bpo-41686: Refactor signal_exec() (GH-23346)
cda23be

New changeset 05a5d69 by Victor Stinner in branch '3.9':
bpo-41686: Always create the SIGINT event on Windows (GH-23344) (GH-23347)
05a5d69

New changeset a702bd4 by Victor Stinner in branch '3.8':
bpo-41686: Always create the SIGINT event on Windows (GH-23344) (GH-23347) (GH-23349)
a702bd4

Ok, the issue should now be fixed in 3.8, 3.9 and master branches. Thanks for the bug report hafiz bilal.

New changeset 29aa624 by Victor Stinner in branch 'master':
bpo-41686: Move _Py_RestoreSignals() to signalmodule.c (GH-23353)
29aa624

bpo-41686: Move _Py_RestoreSignals() to signalmodule.c (GH-23353)

Sorry, this change was for bpo-41713.