std::lock

 

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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)
Exclusão mútua 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)
Gestão de bloqueio genérico 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_ttry_to_lock_tadopt_lock_t (C++11)(C++11)(C++11)	lock (C++11) try_lock (C++11) defer_locktry_to_lockadopt_lock (C++11)(C++11)(C++11)
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promise (C++11) future (C++11) shared_future (C++11) packaged_task (C++11) async (C++11)	launch (C++11) future_status (C++11) future_error (C++11) future_category (C++11) future_errc (C++11)

 

Definido no cabeçalho <mutex>
template<class Lockable1, class Lockable2, class LockableN... > void lock( Lockable1& lock1, Lockable2& lock2, LockableN& lockn... );		(desde C++11)

Bloqueia o dado Lockable objetos lock1, lock2, ..., lockn usando um algoritmo de evitar impasse para evitar bloqueio.

Original:

Locks the given Lockable objects lock1, lock2, ..., lockn using a deadlock avoidance algorithm to avoid deadlock.

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Os objetos estão bloqueadas por uma série não especificada de chamadas para lock, try_lock, unlock. Se uma chamada para lock ou unlock resulta em uma exceção, unlock é chamado por quaisquer objetos bloqueados antes relançando.

Original:

The objects are locked by an unspecified series of calls to lock, try_lock, unlock. If a call to lock or unlock results in an exception, unlock is called for any locked objects before rethrowing.

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Parâmetros

lock1, lock2, ... , lockn

-

o Lockable objetos para bloquear Original: the Lockable objects to lock The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

Valor de retorno

(Nenhum)

Original:

(none)

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Exemplo

O exemplo a seguir usa std::lock para bloquear pares de semáforos sem impasse .

Original:

The following example uses std::lock to lock pairs of mutexes without deadlock.

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#include <mutex>#include <thread>#include <iostream>#include <vector>#include <functional>#include <chrono>   struct Employee { Employee(int id): id(id){}int id;std::vector<int> lunch_partners;std::mutex m;};   void send_mail(Employee &e1, Employee &e2){// simulate a time-consuming messaging operationstd::this_thread::sleep_for(std::chrono::seconds(1));}   void assign_lunch_partner(Employee &e1, Employee &e2){// use std::lock to acquire two locks without worrying about // other calls to assign_lunch_partner deadlocking us std::lock(e1.m, e2.m);   e1.lunch_partners.push_back(e2.id); e2.lunch_partners.push_back(e1.id);   e1.m.unlock(); e2.m.unlock();   send_mail(e1, e2); send_mail(e2, e1);}   int main(){ Employee alice(0), bob(1), christina(2), dave(3);   // assign in parallel threads because mailing users about lunch assignments// takes a long timestd::vector<std::thread> threads; threads.emplace_back(assign_lunch_partner, std::ref(alice), std::ref(bob)); threads.emplace_back(assign_lunch_partner, std::ref(christina), std::ref(bob)); threads.emplace_back(assign_lunch_partner, std::ref(christina), std::ref(alice)); threads.emplace_back(assign_lunch_partner, std::ref(dave), std::ref(bob));   for(auto&thread : threads) thread.join();}

Veja também

try_lock (C++11)	tentativas de obter a propriedade de semáforos através de chamadas repetidas para try_lock Original: attempts to obtain ownership of mutexes via repeated calls to try_lock The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (modelo de função)