C++ how to implment a stoppable future function call? -

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i want execute function after timeout period, like:

sleep(1000);  dowork();

but before timeout reached, can stop execution in thread or other thread, like:

if(somecondition) {     stop dowork() not started. }

is there existing std/boost class kind of task?

you may use combination of variable indicating whether work needs done combined timed condition variable: you'd wait sleep time , if wait terminates you'd check if work should aborted, more sleeping needed (condition variables can stop waiting spuriously), or work can started:

bool                    do_work(true); std::mutex              mutex; std::condition_variable condition;  std::chrono::time_point<std::chrono::steady_clock> abs_time(      std::chrono::steady_clock::now() + std::chrono::milliseconds(1000)); std::unique_lock<std::mutex> kerberos; if (condition.wait_until(kerberos, abs_time, [&]{ return do_work; })) {     // work }

the other thread cancelling work acquire lock mutex, set do_work false, , notify_one() condition variable.


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