Running two functions at the same time. (Real Time)

Question

I was not able to do this. What I want is this, While the code is working in real time, the user will be able to take any action he wants.

  (...)

int main (){

    time = 60; 
    string input;

    cout << "Time: " << time << endl << endl; // Time needs to decrease every second. 
    // (time--,sleep(1000))
    cout << "Input: ";
    cin >> Input; // The user can take the action he wants at this time.

  (...)
}

I'm waiting for your help, thank you.

not completely clear what you want that code to do. What two functions should run at the same time? What do you mean with "take any action" ? — 463035818_is_not_an_ai, Mar 30 '20 at 19:13
In other words, while time is running out, the user can use the "cin" function, but he should see the time decreasing on the screen. — , Mar 30 '20 at 19:18
Maybe a duplicate to this [Running a timer while other commands are being executed c++](https://stackoverflow.com/questions/36877961), but it should be noted that the suggested solution does not work well. — t.niese, Mar 30 '20 at 19:21
As [this question's answer](https://stackoverflow.com/questions/9053175/is-it-possible-to-set-timeout-for-stdcin) tells, you cannot use `std::cin` for your job. You may want to search other functions that take input asynchroniously. — Tudor, Mar 30 '20 at 19:23
[is this question related?](https://stackoverflow.com/questions/6736536/c-input-and-output-to-the-console-window-at-the-same-time) — Antonin GAVREL, Mar 30 '20 at 20:03
Thanks [is this question related?](https://stackoverflow.com/questions/6736536/c-input-and-output-to-the-console-window-at-the-same-time) this works! — , Mar 30 '20 at 20:20

score 0 · Accepted Answer · answered Mar 30 '20 at 19:37

You can use std::thread to have a second thread of execution. That thread can sleep 60 times for std::chrono::seconds{1} each tick. That second thread can write to std::cout. But this can mix with the input the user is typing! This can be quite confusing. Also, after those 60 seconds the user still needs to enter something.

Formally: It's not Undefined Behavior. It won't crash.

Running two functions at the same time. (Real Time)

1 Answers1