std::unique_lock

 

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Atomic types atomic (C++11) atomic_ref (C++20) atomic_flag (C++11) Initialization of atomic types atomic_init (C++11)(deprecated in C++20) ATOMIC_VAR_INIT (C++11)(deprecated in C++20) ATOMIC_FLAG_INIT (C++11) Memory ordering memory_order (C++11) kill_dependency (C++11) atomic_thread_fence (C++11) atomic_signal_fence (C++11) 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)

 

std::unique_lock

Member functions

unique_lock::unique_lock

unique_lock::~unique_lock

unique_lock::operator=

Locking

unique_lock::lock

unique_lock::try_lock

unique_lock::try_lock_for

unique_lock::try_lock_until

unique_lock::unlock

Modifiers

unique_lock::swap

unique_lock::release

Observers

unique_lock::mutex

unique_lock::owns_lock

unique_lock::operator bool

Non-member functions

swap(std::unique_lock)

 

Defined in header <mutex>
template< class Mutex > class unique_lock;		(since C++11)

The class unique_lock implements general-purpose mutex ownership wrapper allowing deferred locking, timed locking, recursive locking, transfer of lock ownership, and use with condition variables. The class is non-copyable but movable.

Member types

Type	Definition
mutex_type	Mutex

Member functions

(constructor)	constructs a unique_lock, optionally locking (i.e., taking ownership of) the supplied mutex (public member function)
(destructor)	unlocks (i.e., releases ownership of) the associated mutex, if owned (public member function)
operator=	unlocks (i.e., releases ownership of) the mutex, if owned, and acquires ownership of another (public member function)
Locking
lock	locks (i.e., takes ownership of) the associated mutex (public member function)
try_lock	tries to lock (i.e., takes ownership of) the associated mutex without blocking (public member function)
try_lock_for	attempts to lock (i.e., takes ownership of) the associated TimedLockable mutex, returns if the mutex has been unavailable for the specified time duration (public member function)
try_lock_until	tries to lock (i.e., takes ownership of) the associated TimedLockable mutex, returns if the mutex has been unavailable until specified time point has been reached (public member function)
unlock	unlocks (i.e., releases ownership of) the associated mutex (public member function)
Modifiers
swap	swaps state with another std::unique_lock (public member function)
release	disassociates the associated mutex without unlocking (i.e., releasing ownership of) it (public member function)
Observers
mutex	returns a pointer to the associated mutex (public member function)
owns_lock	tests whether the lock owns (i.e., has locked) its associated mutex (public member function)
operator bool	tests whether the lock owns (i.e., has locked) its associated mutex (public member function)

Non-member functions

std::swap(std::unique_lock) (C++11)

specializes the std::swap algorithm (function template)