Repeatedly execute a task in C++

This post will discuss how to repeatedly execute a task in C++.

In programming, threads are often used for the concurrent execution of multiple functions. In C++, the std::thread class offers the facility for threads to schedule tasks for repeated execution. Consider the following code which implements a simple timer. The code uses std::this_thread::sleep_until which blocks the execution of the current thread until the specified duration has been reached.

#include <iostream>

#include <chrono>

#include <thread>

#include <functional>

void run(std::function<void(void)> f, int duration)

{

std::thread([f, duration]() {

while (true)

{

f();

auto ms = std::chrono::steady_clock::now() + std::chrono::milliseconds(duration);

std::this_thread::sleep_until(ms);

}

}).detach();

}

void foo() {

std::cout << "Running.." << std::endl;

}

int main()

{

run(foo, 1000);

while (true);

}

Download Code

Note that the above solution repeatedly executes the specified function until the program is terminated. Here’s an alternative version using the std::this_thread::sleep_for which blocks the execution of the current thread for the specified duration.