Allactivecalls on the sameflagform a single total order consisting of zero or moreexceptionalcalls, followed by onereturningcall. The end of eachactivecall synchronizes-with the nextactivecall in that order. The return from thereturningcall synchronizes-with the returns from allpassivecalls on the...
void run_one(int &n){ std::call_once(flag, [&n]{n=n+1;}); //只执行一次, 适合延迟加载; 多线程static变量情况 } int main () { std::vector<std::thread> ver; int num = 0; for (auto i = 0; i < 10; ++i){ ver.emplace_back(print_block,50,'*'); ver.emplace_back(run_...
once_flag m_flg; }; void function_2(LogFile2 &log) { string newstr = "Hello"; log.Shared_Print2(newstr, 32); } std::deque<int> q; std::mutex m_Mu; std::condition_variable cond; //生产者 void Funcation_One() { int count = 10; while (count > 9) { std::unique_lock<...
std::atomic<bool> name(false); std::atomic_flag name = ATOMIC_FLAG_INIT; 成员函数表: 名称 作用 operator= 重载等 clear 将布尔值设置为 false test_and_set 将布尔值设置为 true 并返回先前值 test【std20】 原子的返回当前值 wait 阻塞线程至被提醒且原子值更改 notify_one【std20】 通知至少一个...
notify_one(); } sleep(1); } } int main() { std::thread td1(func1); std::thread td2(func2); td1.join(); td2.join(); return 0; } ref和cref 对于参数传递,我们有时候会需要传递引用,但是跨线程不能直接用引用来传递,需要对参数用ref和cref传递。 void func(const std::string& str...
在多线程编程中,有时某个任务只需要执行一次,此时可以用C++11中的std::call_once函数配合std::once_flag来实现。如果多个线程需要同时调用某个函数,std::call_once可以保证多个线程对该函数只调用一次。也可用在解决线程安全的单例模式。C++11中的std::call_once函数位于<mutex>头文件中。template<classCall ...
produce4.notify_one(); } static void producer(int id) { std::unique_lock<std::mutex> lck(mtx4); while (cargo4 != 0) produce4.wait(lck); cargo4 = id; consume4.notify_one(); } int test_condition_variable_notify_one() {
All active calls on the same flag form a single total order consisting of zero or more exceptional calls, followed by one returning call. The end of each active call synchronizes-with the next active call in that order. The return from the returning call synchronizes-with the returns from ...
missingflag— Missing value condition "includemissing" (default) | "includenan" | "includenat" | "omitmissing" | "omitnan" | "omitnat" Missing value condition, specified as one of the values in this table. ValueInput Data TypeDescription "includemissing" (since R2023a) All supported data...
std::atomic_flag_clear, std::atomic_flag_clear_explicit std::atomic_flag_test, std::atomic_flag_test_explicit std::atomic_flag_wait, std::atomic_flag_wait_explicit std::atomic_flag_notify_one std::atomic_flag_notify_all std::atomic_init ATOMIC_VAR_INIT ATOMIC_FLAG_INIT std::memory_orde...