C++11 并发指南之std::thread 详解

#include <iostream>
#include <utility>
#include <thread>
#include <chrono>
#include <functional>
#include <atomic>
 
void f1(int n)
{
  for (int i = 0; i < 5; ++i) {
    std::cout << "Thread " << n << " executing\n";
    std::this_thread::sleep_for(std::chrono::milliseconds(10));
  }
}
 
void f2(int& n)
{
  for (int i = 0; i < 5; ++i) {
    std::cout << "Thread 2 executing\n";
    ++n;
    std::this_thread::sleep_for(std::chrono::milliseconds(10));
  }
}
 
int main()
{
  int n = 0;
  std::thread t1; // t1 is not a thread
  std::thread t2(f1, n + 1); // pass by value
  std::thread t3(f2, std::ref(n)); // pass by reference
  std::thread t4(std::move(t3)); // t4 is now running f2(). t3 is no longer a thread
  t2.join();
  t4.join();
  std::cout << "Final value of n is " << n << '\n';
}

#include <stdio.h>
#include <stdlib.h>

#include <chrono>  // std::chrono::seconds
#include <iostream> // std::cout
#include <thread>  // std::thread, std::this_thread::sleep_for

void thread_task(int n) {
  std::this_thread::sleep_for(std::chrono::seconds(n));
  std::cout << "hello thread "
    << std::this_thread::get_id()
    << " paused " << n << " seconds" << std::endl;
}

/*
 * === FUNCTION =========================================================
 *     Name: main
 * Description: program entry routine.
 * ========================================================================
 */
int main(int argc, const char *argv[])
{
  std::thread threads[5];
  std::cout << "Spawning 5 threads...\n";
  for (int i = 0; i < 5; i++) {
    threads[i] = std::thread(thread_task, i + 1);
  }
  std::cout << "Done spawning threads! Now wait for them to join\n";
  for (auto& t: threads) {
    t.join();
  }
  std::cout << "All threads joined.\n";

  return EXIT_SUCCESS;
} /* ---------- end of function main ---------- */