std::future<T>::share

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Concurrency support library

Threads

thread

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jthread

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hardware_destructive_interference_sizehardware_constructive_interference_size

(C++17)(C++17)

this_thread namespace

get_id (C++11)
yield (C++11)

sleep_for (C++11)
sleep_until (C++11)

Cooperative cancellation

stop_token (C++20)
inplace_stop_token (C++26)
never_stop_token (C++26)
stop_source (C++20)
inplace_stop_source (C++26)
stop_callback (C++20)

inplace_stop_callback (C++26)
stop_callback_for_t (C++26)
stoppable_token (C++26)
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stoppable-source (C++26)
stoppable-callback-for (C++26)

Mutual exclusion

mutex (C++11)
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Condition variables

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promise (C++11)
future (C++11)
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packaged_task (C++11)
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launch (C++11)
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future_category (C++11)
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Safe reclamation

rcu_obj_base (C++26)
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rcu_synchronize (C++26)
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Atomic types
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atomic_flag (C++11)
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memory_order (C++11)
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Free functions for atomic operations
atomic_storeatomic_store_explicit (C++11)(C++11)
atomic_loadatomic_load_explicit (C++11)(C++11)
atomic_exchangeatomic_exchange_explicit (C++11)(C++11)
atomic_compare_exchange_weakatomic_compare_exchange_weak_explicitatomic_compare_exchange_strongatomic_compare_exchange_strong_explicit (C++11)(C++11)(C++11)(C++11)
atomic_fetch_addatomic_fetch_add_explicit (C++11)(C++11)
atomic_fetch_subatomic_fetch_sub_explicit (C++11)(C++11)
atomic_fetch_andatomic_fetch_and_explicit (C++11)(C++11)
atomic_fetch_oratomic_fetch_or_explicit (C++11)(C++11)
atomic_fetch_xoratomic_fetch_xor_explicit (C++11)(C++11)
atomic_fetch_maxatomic_fetch_max_explicit (C++26)(C++26)
atomic_fetch_minatomic_fetch_min_explicit (C++26)(C++26)
atomic_is_lock_free (C++11)
atomic_waitatomic_wait_explicit (C++20)(C++20)
atomic_notify_one (C++20)
atomic_notify_all (C++20)
Free functions for atomic flags
atomic_flag_test_and_setatomic_flag_test_and_set_explicit (C++11)(C++11)
atomic_flag_clearatomic_flag_clear_explicit (C++11)(C++11)
atomic_flag_testatomic_flag_test_explicit (C++20)(C++20)
atomic_flag_waitatomic_flag_wait_explicit (C++20)(C++20)
atomic_flag_notify_one (C++20)
atomic_flag_notify_all (C++20)

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std::future

Member functions
future::future
future::~future
future::operator=
future::share
Getting the result
future::get
State
future::valid
future::wait
future::wait_for
future::wait_until

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std::shared_future<T> share()noexcept;

Transfers the shared state of*this, if any, to astd::shared_future object. Multiplestd::shared_future objects may reference the same shared state, which is not possible withstd::future.

After callingshare on astd::future,valid()==false.