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std::recursive_timed_mutex::try_lock_until

From cppreference.com
 
 
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template< class Clock, class Duration >
bool try_lock_until( const std::chrono::time_point<Clock, Duration>& timeout_time );
(since C++11)

Tries to lock the mutex. Blocks until specified timeout_time has been reached (timeout) or the lock is acquired (owns the mutex), whichever comes first. On successful lock acquisition returns true, otherwise returns false.

If timeout_time has already passed, this function behaves like try_lock().

Clock must meet the Clock requirements. The program is ill-formed if std::chrono::is_clock_v<Clock> is false.(since C++20)

The standard recommends that the clock tied to timeout_time be used, in which case adjustments of the clock may be taken into account. Thus, the duration of the block might be more or less than timeout_time - Clock::now() at the time of the call, depending on the direction of the adjustment and whether it is honored by the implementation. The function also may block until after timeout_time has been reached due to process scheduling or resource contention delays.

As with try_lock(), this function is allowed to fail spuriously and return false even if the mutex was not locked by any other thread at some point before timeout_time.

Prior unlock() operation on the same mutex synchronizes-with (as defined in std::memory_order) this operation if it returns true.

A thread may call try_lock_until on a recursive mutex repeatedly. Successful calls to try_lock_until increment the ownership count: the mutex will only be released after the thread makes a matching number of calls to unlock.

The maximum number of levels of ownership is unspecified. A call to try_lock_until will return false if this number is exceeded.

Contents

[edit] Parameters

timeout_time - maximum time point to block until

[edit] Return value

true if the lock was acquired successfully, otherwise false.

[edit] Exceptions

Any exception thrown by timeout_time (clocks, time points, and durations provided by the standard library never throw).

[edit] Example

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 2093 C++11 try_lock_until threw nothing throws timeout-related exceptions

[edit] See also

locks the mutex, blocks if the mutex is not available
(public member function) [edit]
tries to lock the mutex, returns if the mutex is not available
(public member function) [edit]
tries to lock the mutex, returns if the mutex has been
unavailable for the specified timeout duration
(public member function) [edit]
unlocks the mutex
(public member function) [edit]
C documentation for mtx_timedlock