C++11 并发指南二(std::thread 详解)2013-08-04 13:37 by Haippy, 2999 阅读, 2 评论, 收藏, 编辑上一篇博客《C++11 并发指南一(C++11 多线程初探)》中只是提到了 std::thread 的基本用法,并给出了一个最简单的例子,本文将稍微详细地介绍 std::thread 的用法。 std::thread 在 <thread> 头文件中声明,因此使用 std::thread 时需要包含 <thread> 头文件。 std::thread 构造
std::thread 各种构造函数例子如下(参考): #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'; } move 赋值操作
请看下面的例子: #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 ---------- */ 其他成员函数
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