std::recursive_timed_mutex::try_lock_until
bool try_lock_until( const std::chrono::time_point <Clock, Duration>& timeout_time );
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.
[edit] Parameters
[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
Reason: no 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
unavailable for the specified timeout duration
(public member function) [edit]