The following code example is taken from the book
The C++ Standard Library - A Tutorial and Reference, 2nd Edition
by Nicolai M. Josuttis, Addison Wesley Longman, 2012
Copyright © 2012 by Pearson Education, Inc. and Nicolai M. Josuttis
#include <future>
#include <list>
#include <iostream>
#include <exception>
using namespace std;
void task1()
{
// endless insertion and memory allocation
// - will sooner or later raise an exception
// - BEWARE: this is bad practice
list<int> v;
while (true) {
for (int i=0; i<1000000; ++i) {
v.push_back(i);
}
cout.put('.').flush();
}
}
int main()
{
cout << "starting 2 tasks" << endl;
cout << "- task1: process endless loop of memory consumption" << endl;
cout << "- task2: wait for <return> and then for task1" << endl;
auto f1 = async(task1); // start task1() asynchronously (now or later or never)
cin.get(); // read a character (like getchar())
cout << "\nwait for the end of task1: " << endl;
try {
f1.get(); // wait for task1() to finish (raises exception if any)
}
catch (const exception& e) {
cerr << "EXCEPTION: " << e.what() << endl;
}
}