std::timed_mutex::try_lock_until
| 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 or the lock is acquired, 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.
If try_lock_until is called by a thread that already owns the mutex, the behavior is undefined.
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 clock, time_point, or duration during the execution (clocks, time points, and durations provided by the standard library never throw)
[edit] Example
This example shows a 10 seconds block
#include <thread> #include <iostream> #include <chrono> #include <mutex> std::timed_mutex test_mutex; void f() { auto now=std::chrono::steady_clock::now(); test_mutex.try_lock_until(now + std::chrono::seconds(10)); std::cout << "hello world\n"; } int main() { std::lock_guard<std::timed_mutex> l(test_mutex); std::thread t(f); t.join(); }
[edit] See also
| locks the mutex, blocks if the mutex is not available (public member function) | |
| tries to lock the mutex, returns if the mutex is not available (public member function) | |
| tries to lock the mutex, returns if the mutex has been unavailable for the specified timeout duration (public member function) | |
| unlocks the mutex (public member function) | |
| C documentation for mtx_timedlock
| |
