std::shared_lock<Mutex>::try_lock_for

 

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std::shared_lock

Member functions

shared_lock::shared_lock

shared_lock::~shared_lock

shared_lock::operator=

Shared locking

shared_lock::lock

shared_lock::try_lock

shared_lock::try_lock_for

shared_lock::try_lock_until

shared_lock::unlock

Modifiers

shared_lock::swap

shared_lock::release

Observers

shared_lock::mutex

shared_lock::owns_lock

shared_lock::operator bool

Non-member functions

swap(std::shared_lock)

 

template< class Rep, class Period > bool try_lock_for( const std::chrono::duration<Rep,Period>& timeout_duration );		(since C++14)

Tries to lock the associated mutex in shared mode. Blocks until specified timeout_duration has elapsed or the lock is acquired, whichever comes first. On successful lock acquisition returns true, otherwise returns false. Effectively calls mutex()->try_lock_shared_for(timeout_duration).

This function may block for longer than timeout_duration due to scheduling or resource contention delays.

The standard recommends that a steady clock is used to measure the duration. If an implementation uses a system clock instead, the wait time may also be sensitive to clock adjustments.

std::system_error is thrown if there is no associated mutex or if the mutex is already locked.

The behavior is undefined if Mutex does not meet the SharedTimedLockable requirements.

Parameters

timeout_duration

-

maximum duration to block for

Return value

true if the ownership of the mutex has been acquired successfully, false otherwise.

Exceptions

• Any exceptions thrown by mutex()->try_lock_shared_for(timeout_duration).

• If there is no associated mutex, std::system_error with an error code of std::errc::operation_not_permitted.

• If the mutex is already locked, std::system_error with an error code of std::errc::resource_deadlock_would_occur.

See also

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 of std::unique_lock<Mutex>)
lock	locks the associated mutex (public member function)
try_lock	tries to lock the associated mutex (public member function)
try_lock_until	tries to lock the associated mutex, until a specified time point (public member function)
unlock	unlocks the associated mutex (public member function)