scheduler->scheduleAndReplyValue

[cjbd]

hello, i'm integrating my other c++ modules into this, which involves calling some long time tasks, i'm looking at async task test: scheduleAndReplyValue, which seems to fit the job, i'm changing it to something like this:

void lauchTask() {
    std::thread::id caller_id = std::this_thread::get_id();

    auto runInBackground = [caller_id]() -> std::string {
        // remote long time task here
       return "something";
    };
    auto onResult = [caller_id](std::string res) {
        // do something with res
    };

    std::shared_ptr<mbgl::Scheduler> sheduler = mbgl::Scheduler::GetBackground();
    sheduler->scheduleAndReplyValue(mbgl::util::SimpleIdentity::Empty, runInBackground, onResult);
}

question:

1. is this the correct way for background task which would take long time?
2. is it safe to launch such task multiple times, do i need to do some clean up?
3. is thread pool being used or each time new thread will be created?

thanks!