cppreference 给出的官方解释: A condition variable is an object able to block the calling thread until notified to resume. It uses a unique_lock (over a mutex) to lock the thread when one of its wait functions is cal
Even if the shared variable is atomic, it must be modified while owning the mutex tocorrectlypublish the modification to the waiting thread. Any thread that intends to wait on astd::condition_variablemust: Acquire astd::unique_lock<std::mutex>on the mutex used to protect the shared variable....
std::condition_variable:: C++ 并发支持库 std::condition_variable voidwait(std::unique_lock<std::mutex>&lock); (1)(C++11 起) template<classPredicate> voidwait(std::unique_lock<std::mutex>&lock, Predicate pred); (2)(C++11 起) wait导致当前线程阻塞直至条件变量被通知,或虚假唤醒发生。可以...
namespacestd{classcondition_variable;classcondition_variable_any;voidnotify_all_at_thread_exit(condition_variable&cond, unique_lock<mutex>lk);enumclasscv_status{no_timeout, timeout};} Classstd::condition_variable namespacestd{classcondition_variable{public:condition_variable();~condition_variable();co...
condition_variable cv;//线程A,producervoidtask1(){inti =0;while(true) {unique_lock<mutex>lock(mtx);if(q.size() <1000) {if(i <99) { q.push_back(i); cv.notify_one();//cv.notify_all();i++; }else{ i =0; } }else{ ...
c++ condition_variable的wait 语法糖 最近在复盘之前用到的线程同步的一些知识点,话不多说,先看个例子吧: 摘自:http://www.cplusplus.com/reference/condition_variable/condition_variable/wait/ //condition_variable::wait (with predicate)#include <iostream>//std::cout#include <thread>//std::thread, std...
for (auto& th : threads) th.join(); return 0; } // reference: http://en.cppreference.com/w/cpp/thread/condition_variable std::mutex m; std::condition_variable cv6; std::string data; bool ready6 = false; bool processed = false; static void worker_thread() { // Wait until main...
From cppreference.com <cpp |thread |condition variable C++ native_handle_type native_handle(); (since C++11) Accesses the native handle of*this. The meaning and the type of the result of this function is implementation-defined. On a POSIX system, this may be a value of typepthread...
我对std::condition_variable的使用有点困惑。我知道在调用mutex之前,我必须在unique_lockcondition_variable.wait()。我找不到的是在调用notify_one()或notify_all()之前是否也应该获取唯一锁。 cppreference.com上的示例相互矛盾。例如,notify_one 页面给出了这个例子: ...
先贴一个condition_variable的讲解:https://en.cppreference.com/w/cpp/thread/condition_variable,很详细也很全面,但是是英文的,劝退了一部分英语不好的人(也包括我),但是借助翻译还是大概可以看下来的,而且里面的两个代码也很有代表性,使用的生产者消费者模式,推给大家。