std::future - cppreference.com std::promise - cppreference.com https://en.cppreference.com/w/cpp/thread/packaged_task
#include <algorithm>#include <future>#include <iostream>#include <mutex>#include <numeric>#include <string>#include <vector>std::mutexm;structX{voidfoo(inti,conststd::string&str){std::lock_guard<std::mutex>lk(m);std::cout<<str<<' '<<i<<'\n';}voidbar(conststd::string&str){std:...
std::ref(promise));do_some_other_things();std::cout<<result.get()<<std::endl;th.join();...
AI代码解释 #include<iostream>#include<future>#include<thread>intfun(int x,std::promise<int>&p){x++;x*=10;p.set_value(x);std::cout<<std::this_thread::get_id()<<std::endl;returnx;}intmain(){std::promise<int>p;std::future<int>fu=p.get_future();// 并将结果返回给futurestd::...
std::threadt2(get_task_value, std::ref(future));// 获取线程函数值的线程 t1.join(); t2.join(); return0; } 可以通过查询future的状态来获取异步任务的执行情况,例如,可以在上面的代码中添加future的状态查询,直到任务完成为止。 future的状态为 future_status , 共有三种状态: ...
近期发现项目组使用新版本的opentelemetry-cpp的时候偶现崩溃。崩溃的位置在STL的std::future析构的地方,而这个std::future由std::async创建。 比较违反直觉,这里记录分享一下分析和解决过程方面其他碰到的小伙伴们。 问题分析 相关代码和规范 首先我们来看下相关代码: ...
std::future<int> fu = std::async(sums,3,4,5);//std::future<int> fu = std::async(sum,std::ref(x),std::ref(y));std::cout << fu.get() << std::endl;//获取当前计算机线程数量std::cout << std::thread::hardware_concurrency() << std::endl;//获取当前线程IDstd::cout << ...
Exception thrown at 0x00007FFC0323A799 in cpptests.exe: Microsoft C++ exception: std::bad_alloc at memory location 0x000000F77DEFEF20. This is because in nameCallback we try to access a member of the User structure. However, since the object of this type was deleted (via pJohn.reset...
arr.size() : (i + 1) * chunkSize; futures.push_back(std::async(std::launch::async, processArray, std::ref(arr), start, end)); } // 等待所有异步任务完成 for (auto& future : futures) { future.wait(); } // 输出处理后的数组 for (int num : arr) { std::cout << num << ...
void test() { //封装一个异步操作 std::packaged_task<int()> task([]() { std::this_thread::sleep_for(std::chrono::seconds(5)); return 7; }); std::thread t1(std::ref(task)); std::future<int> f1 = task.get_future(); std::cout << "Waiting..." << std::endl; std::fu...