std::condition_variable::wait_for

 

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Threads Original: Threads The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
thread (C++11)
this_thread Namespace Original: this_thread namespace The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
get_id (C++11) yield (C++11)	sleep_for (C++11) sleep_until (C++11)
Gegenseitigen Ausschluss Original: Mutual exclusion The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
mutex (C++11) timed_mutex (C++11)	recursive_mutex (C++11) recursive_timed_mutex (C++11)
Generische Sperrverwaltung Original: Generic lock management The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
lock_guard (C++11) unique_lock (C++11) defer_lock_t try_to_lock_t adopt_lock_t (C++11) (C++11) (C++11)	lock (C++11) try_lock (C++11) defer_lock try_to_lock adopt_lock (C++11) (C++11) (C++11)
Zustand Variablen Original: Condition variables The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
condition_variable (C++11)
condition_variable_any (C++11)
notify_all_at_thread_exit (C++11)
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std::condition_variable

Member-Funktionen Original: Member functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

condition_variable::condition_variable

condition_variable::~condition_variable

Notification Original: Notification The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

condition_variable::notify_one

condition_variable::notify_all

Warten Original: Waiting The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

condition_variable::wait

condition_variable::wait_for

condition_variable::wait_until

Ureinwohner Griff Original: Native handle The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

condition_variable::native handle

 

template<class Rep, class Period > std::cv_status wait_for(std::unique_lock<std::mutex>& lock,                          conststd::chrono::duration<Rep, Period>& rel_time);	(1)	(seit C++11)
template<class Rep, class Period, class Predicate > bool wait_for(std::unique_lock<std::mutex>& lock,                conststd::chrono::duration<Rep, Period>& rel_time,                Predicate pred);	(2)	(seit C++11)

1)

Atomar freigibt lock, blockiert den aktuellen ausgeführten Threads, und fügt sie in die Liste der wartenden Threads auf *this. Der Faden wird entsperrt, wenn notify_all() oder notify_one() ausgeführt werden, oder wenn die relative Timeout rel_time abläuft. Es kann auch fälschlicherweise entsperrt werden. Wenn freigegeben, egal aus welchem ​​Grund, ist lock reacquired und wait_for() beendet. Wenn diese Funktion tritt über Ausnahme ist lock auch zurückerworben .

Original:

Atomically releases lock, blocks the current executing thread, and adds it to the list of threads waiting on *this. The thread will be unblocked when notify_all() or notify_one() is executed, or when the relative timeout rel_time expires. It may also be unblocked spuriously. When unblocked, regardless of the reason, lock is reacquired and wait_for() exits. If this function exits via exception, lock is also reacquired.

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2)

Entspricht

Original:

Equivalent to

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while(!pred())
    if(wait_for(lock, rel_time)==std::cv_status::timeout)
        return pred();
returntrue;

Diese Überlastung kann verwendet werden, um falsche Erwachen ignorieren .

Original:

This overload may be used to ignore spurious awakenings.

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Parameter

lock	-	ein Objekt des Typs std::unique_lock<std::mutex>, die durch den aktuellen Thread gesperrt werden muss Original: an object of type std::unique_lock<std::mutex>, which must be locked by the current thread The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
rel_time	-	ein Objekt vom Typ std::chrono::duration, die die maximale Zeit mit Warten verbringen Original: an object of type std::chrono::duration representing the maximum time to spend waiting The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
pred	-	predicate which returns ​false wenn das Warten sollte fortgesetzt werden Original: if the waiting should be continued The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. . The signature of the predicate function should be equivalent to the following:  bool pred();​

Rückgabewert

1)

std::cv_status::timeout wenn die relative Timeout durch rel_time angegebenen abgelaufen, std::cv_status::no_timeout overwise .

Original:

std::cv_status::timeout if the relative timeout specified by rel_time expired, std::cv_status::no_timeout overwise.

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2)

false wenn das Prädikat pred noch ausgewertet false nach dem rel_time Timeout abgelaufen, sonst true .

Original:

false if the predicate pred still evaluates to false after the rel_time timeout expired, otherwise true.

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Ausnahmen

Kann std::system_error werfen, kann auch propagieren Ausnahmen lock.lock() geworfen oder lock.unlock() .

Original:

May throw std::system_error, may also propagate exceptions thrown by lock.lock() or lock.unlock().

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Notes

Der Aufruf dieser Funktion, wenn lock.mutex() nicht durch den aktuellen Thread gesperrt ist undefiniert .

Original:

Calling this function if lock.mutex() is not locked by the current thread is undefined behavior.

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Der Aufruf dieser Funktion, wenn lock.mutex() nicht das gleiche Mutex als ein von allen anderen Threads, wartet derzeit auf der gleichen Bedingung variabel ist undefiniert verwendet .

Original:

Calling this function if lock.mutex() is not the same mutex as the one used by all other threads that are currently waiting on the same condition variable is undefined behavior.

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Beispiel

#include <iostream>#include <atomic>#include <condition_variable>#include <thread>#include <chrono>   std::condition_variable cv;std::mutex cv_m;std::atomic<int> i =ATOMIC_VAR_INIT(0);   void waits(int idx){std::unique_lock<std::mutex> lk(cv_m);if(cv.wait_for(lk, std::chrono::milliseconds(idx*100), [](){return i ==1;}))std::cerr<<"Thread "<< idx <<" finished waiting. i == "<< i <<'\n';elsestd::cerr<<"Thread "<< idx <<" timed out. i == "<< i <<'\n';}   void signals(){std::this_thread::sleep_for(std::chrono::milliseconds(120));std::cerr<<"Notifying...\n"; cv.notify_all();std::this_thread::sleep_for(std::chrono::milliseconds(100)); i =1;std::cerr<<"Notifying again...\n"; cv.notify_all();}   int main(){std::thread t1(waits, 1), t2(waits, 2), t3(waits, 3), t4(signals); t1.join(); t2.join(), t3.join(), t4.join();}

Output:

Thread 1 timed out. i == 0 Notifying... Thread 2 timed out. i == 0 Notifying again... Thread 3 finished waiting. i == 1

Siehe auch

wait	Blockiert den aktuellen Thread, bis die condition variable geweckt wird Original: blocks the current thread until the condition variable is woken up The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (öffentliche Elementfunktion)
wait_until	Blockiert den aktuellen Thread, bis die condition variable geweckt wird oder bis der angegebenene Zeitpunkt erreicht wurde Original: blocks the current thread until the condition variable is woken up or until specified time point has been reached The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (öffentliche Elementfunktion)