std::future

 

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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 espacio de nombres 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)
Exclusión mutua 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)
Gestión de bloqueos 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)
Las variables de condición 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)
cv_status (C++11)
Futuros Original: Futures The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
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)

 

std::future

future::future

future::~future

future::operator=

future::share

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

future::get

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

future::valid

future::wait

future::wait_for

future::wait_until

 

Definido en la cabecera <future>
template< class T > class future;	(1)	(desde C++11)
template< class T > class future<T&>;	(2)	(desde C++11)
template<>          class future<void>;	(3)	(desde C++11)

La plantilla std::future clase proporciona un mecanismo para acceder al resultado de las operaciones asincrónicas:

Original:

The class template std::future provides a mechanism to access the result of asynchronous operations:

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• Una operación asincrónica (creado por std::async, std::packaged_task o std::promise) puede proporcionar un objeto std::future al creador de esa operación asíncrona .

  Original:

  An asynchronous operation (created via std::async, std::packaged_task, or std::promise) can provide a std::future object to the creator of that asynchronous operation.

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• El creador de la operación asincrónica se puede usar una variedad de métodos para consultar, esperar, o extraer un valor de la std::future. Estos métodos pueden bloquear si la operación asincrónica no ha proporcionado aún un valor .

  Original:

  The creator of the asynchronous operation can then use a variety of methods to query, wait for, or extract a value from the std::future. These methods may block if the asynchronous operation has not yet provided a value.

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• Cuando la operación asincrónica está listo para enviar el resultado al creador, puede hacerlo modificando el estado compartido' (por ejemplo std::promise::set_value) que está vinculado a std::future del creador .

  Original:

  When the asynchronous operation is ready to send a result to the creator, it can do so by modifying shared state (e.g. std::promise::set_value) that is linked to the creator's std::future.

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Tenga en cuenta que las referencias std::future estado compartido que no es compartida con ningún objeto de devolución asincrónica otros (a diferencia de std::shared_future) .

Original:

Note that std::future references shared state that is not shared with any other asynchronous return objects (as opposed to std::shared_future).

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Las funciones miembro

(constructor)	construye el objeto futuro Original: constructs the future object The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (función miembro público)
(destructor)	destructs el objeto futuro Original: destructs the future object The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (función miembro público)
operator=	mueve el objeto futuro Original: moves the future object The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (función miembro público)
share	devuelve una referencia a shared_future el resultado asociado a *this Original: returns a shared_future referring to the result associated to *this The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (función miembro público)
Conseguir el resultado Original: Getting the result The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
get	devuelve el resultado Original: returns the result The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (función miembro público)
Estado Original: State The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
valid	Comprueba si el futuro ha estado compartido con una promesa Original: checks if the future has shared state with a promise The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (función miembro público)
wait	espera a que el resultado esté disponible Original: waits for the result to become available The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (función miembro público)
wait_for	waits for the result, returns if it is not available for the specified timeout duration (función miembro público)
wait_until	espera el resultado, devuelve si no está disponible hasta que el punto de tiempo especificado ha sido alcanzado Original: waits for the result, returns if it is not available 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. (función miembro público)

Ejemplo

#include <iostream>
#include <future>
#include <thread>
 
int main()
{
    // future from a packaged_task
    std::packaged_task<int()> task([](){ return 7; }); // wrap the function
    std::future<int> f1 = task.get_future();  // get a future
    std::thread(std::move(task)).detach(); // launch on a thread
 
    // future from an async()
    std::future<int> f2 = std::async(std::launch::async, [](){ return 8; });
 
    // future from a promise
    std::promise<int> p;
    std::future<int> f3 = p.get_future();
    std::thread( [](std::promise<int>& p){ p.set_value(9); }, 
                 std::ref(p) ).detach();
 
    std::cout << "Waiting...";
    f1.wait();
    f2.wait();
    f3.wait();
    std::cout << "Done!\nResults are: "
              << f1.get() << ' ' << f2.get() << ' ' << f3.get() << '\n';
}

Salida:

Waiting...Done!
Results are: 7 8 9

Ver también

async (C++11)

ejecuta una función asíncrona (posiblemente en un nuevo hilo) y devuelve un std::future que contendrá el resultado Original: runs a function asynchronously (potentially in a new thread) and returns a std::future that will hold the result The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (plantilla de función)

shared_future (C++11)

espera a un valor (posiblemente por referencia por otros futuros) que se establece de forma asincrónica Original: waits for a value (possibly referenced by other futures) that is set asynchronously The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (plantilla de clase)