std::shared_timed_mutex:: try_lock_shared_for
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| Member functions | ||||
| Exclusive locking | ||||
| Shared locking | ||||
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shared_timed_mutex::try_lock_shared_for
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template
<
class
Rep,
class
Period
>
bool try_lock_shared_for ( const std:: chrono :: duration < Rep,Period > & timeout_duration ) ; |
(since C++14) | |
Tries to lock the mutex in shared mode. Blocks until specified timeout_duration has elapsed or the shared lock is acquired, whichever comes first. On successful lock acquisition returns true , otherwise returns false .
If timeout_duration is less or equal timeout_duration. zero ( ) , the function behaves like try_lock_shared() .
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.
As with try_lock_shared() , this function is allowed to fail spuriously and return false even if the mutex was not locked by any other thread at some point during timeout_duration .
Prior unlock() operation on the same mutex synchronizes-with (as defined in std::memory_order ) this operation if it returns true .
If
try_lock_shared_for
is called by a thread that already owns the
mutex
in any mode (shared or exclusive), the behavior is undefined.
Parameters
| timeout_duration | - | maximum duration to block for |
Return value
true if the lock was acquired successfully, otherwise false .
Exceptions
Any exception thrown by clock, time_point, or duration during the execution (clocks, time points, and durations provided by the standard library never throw).
Example
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This section is incomplete
Reason: no example |
See also
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tries to lock the mutex for shared ownership, returns if the mutex is not available
(public member function) |
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tries to lock the mutex for shared ownership, returns if the mutex has been
unavailable until specified time point has been reached (public member function) |
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tries to lock the mutex, returns if the mutex has been
unavailable for the specified timeout duration (public member function) |