std::async 是C++11 引入的一个函数模板,用于异步地执行一个函数,并返回一个 std::future 对象,该对象可用于获取函数的执行结果。 2. 参数 std::async 有两个主要的参数形式: std::future<typename std::result_of<F(Args...)>::type> async(F&& f, Args&&... ...
函数模板std::async异步地运行函数f(有可能在可能是线程池一部分的分离线程中),并返回最终将保有该函数调用结果的std::future。 1)表现如同以std::launch::async|std::launch::deferred作为policy调用(2)。 2)按照特定的启动策略policy(见下文),以参数args调用函数f。
std::future<typenamestd::result_of<Function(Args...)>::type> async(Function&&f, Args&&...args); (1)(seit C++11) template<classFunction,class...Args> std::future<typenamestd::result_of<Function(Args...)>::type> async(std::launchpolicy, Function&&f, Args&&...args); ...
The function templatestd::asyncruns the functionfasynchronously (potentially in a separate thread which might be a part of a thread pool) and returns astd::futurethat will eventually hold the result of that function call. 1)Behaves as if(2)is called withpolicybeingstd::launch::async|std::la...
z.so(OHOS::EventFwk::CommonEventManager::SubscribeCommonEvent(std::__1::shared_ptr<OHOS::EventFwk::CommonEventSubscriber> const&)+56) #05 pc 000000000003253c /system/lib64/module/libcommonevent.z.so #06 pc 0000000000019808 /system/lib64/libace_napi.z.so(NativeAsyncWork::AsyncWorkCall...
std::async是更高级的用法,基于任务的异步操作,大大简化了异步的操作 async(std::launch::async | std::launch::deferred, func, args...); int add(int in) { return in + 1; } int main() { auto res = std::async(add, 2); cout << res.get() << endl; //阻塞直到函数返回 }随机数 ...
tf::Executor executor;// create asynchronous tasks directly from an executorstd::future<int>future= executor.async([](){std::cout<<"async task returns 1\n";return1; }); executor.silent_async([](){std::cout<<"async task does not return\n"; });// create asynchronous tasks with dynam...
std::move std::forward std::thread std::to_string type traits smart pointers std::chrono tuples std::tie std::array unordered containers std::make_shared memory model std::async std::begin/endC++20 Language FeaturesConceptsConcepts are named compile-time predicates which constrain types. They...
co_await 表达式——用于暂停执行,直到恢复: task<> tcp_echo_server() { char data[1024]; while (true) { std::size_t n = co_await socket.async_read_some(buffer(data)); co_await async_write(socket, buffer(data, n)); } }co_yield 表达式——用于暂停执行并返回一个值: ...
目录 收起 std::future Test 实现思路 Todo 应用 接着上一节的右值引用 Future, 来学习cpp的异步,cpp本身提供了Future,Promise, Task, Async这些关键字,但在一些项目中还是封装了自己的类,学习一下异步的实现原理。本身还是引擎渲染的多线程模型太复杂,Async也是多线程的一个应用点,先从简单一点的入门。 【...