std::unique_lock<Mutex>::try_lock_for

 

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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

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unique_lock::mutex

unique_lock::owns_lock

unique_lock::operator bool

Non-member functions

swap(std::unique_lock)

 

template< class Rep, class Period > bool try_lock_for( const std::chrono::duration<Rep, Period>& timeout_duration );		(since C++11)

Tries to lock (i.e., takes ownership of) the associated mutex. 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_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 by this std::unique_lock.

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_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

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	tries to lock the associated mutex, for the specified duration (public member function of std::shared_lock<Mutex>)
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)