[QUESTION] How do I interrupt a exec call?

[LucasBremm]

I am trying to make an application using python code and C++, but I need some kind of protection against infinite loops or too long executions. I tried following some threads and seeing how other people solved their issues, but couldn't find a working solution. I have this example code:

#include <fstream>
#include <iostream>
#include <string>
#include <thread>
#include <atomic>
#include <chrono>
#include <cstdlib>

#include "pybind11/pybind11.h"
#include "pybind11/embed.h"

namespace py = pybind11;

std::atomic<bool> stopped(false);
std::atomic<bool> executed(false);

void python_executor(const std::string &code)
{
  py::gil_scoped_acquire acquire;
  try
  {
      std::cout << "+ Executing python script..." << std::endl;

      py::exec(code);

      std::cout << "+ Finished python script" << std::endl;
  }
  catch (const std::exception &e)
  {
      std::cout << "@ " << e.what() << std::endl;
  }

  executed = true;

  std::cout << "+ Terminated normal" << std::endl;
}

int main()
{
    std::cout << "+ Starting..." << std::endl;

    std::string code = R"(
# infinite_writer.py
import time

file_path = r"C:\Temp\loop.txt"
counter = 1

while True:
    with open(file_path, "a") as f:
        f.write(f"Line {counter}\n")
    counter += 1
    time.sleep(1)  # optional: wait 1 second between writes

)";
    py::scoped_interpreter interpreterGuard{};
    py::gil_scoped_release release;
    std::thread th(python_executor, code);
    auto threadId = th.get_id();
    std::cout << "+ Thread: " << threadId << std::endl;

    // stopped = true;
    int maxExecutionTime = 10;
    auto start = std::chrono::steady_clock::now();
    while (!executed)
    {
      auto elapsed = std::chrono::steady_clock::now() - start;
      if (elapsed > std::chrono::seconds(maxExecutionTime)) {
        std::cout << "Interrupting...";
        PyErr_SetInterrupt();
        std::this_thread::sleep_for(std::chrono::seconds(1));
        if (th.joinable()) {
          th.join();
          executed = true;
          break;
        }
      }
      std::this_thread::sleep_for(std::chrono::seconds(1));
      std::cout << "+ Waiting..." << std::endl;

    }

    // Make sure to join the thread if it's still running
    if (th.joinable()) {
        th.join();
    }

    std::cout << "+ Finished" << std::endl;

    return EXIT_SUCCESS;
}

It's purposely an infinite loop in python, to try and stop it when timeout hits, but it never finishes, I got the following console response:

+ Starting...
+ Thread: 28596
+ Executing python script...
+ Waiting...
+ Waiting...
+ Waiting...
+ Waiting...
+ Waiting...
+ Waiting...
+ Waiting...
+ Waiting...
+ Waiting...
+ Waiting...
Interrupting...

What can I do to correctly end the execution?