tmp/tmpp_mbt8e5/{from.md → to.md}
RENAMED
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@@ -48,12 +48,10 @@ namespace std {
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private:
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mutex_type* pm; // exposition only
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bool owns; // exposition only
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};
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-
template<class Mutex> unique_lock(unique_lock<Mutex>) -> unique_lock<Mutex>;
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-
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template<class Mutex>
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void swap(unique_lock<Mutex>& x, unique_lock<Mutex>& y) noexcept;
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}
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```
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@@ -62,123 +60,113 @@ object within a scope. Ownership of the lockable object may be acquired
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at construction or after construction, and may be transferred, after
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acquisition, to another `unique_lock` object. Objects of type
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`unique_lock` are not copyable but are movable. The behavior of a
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program is undefined if the contained pointer `pm` is not null and the
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lockable object pointed to by `pm` does not exist for the entire
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remaining lifetime
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supplied `Mutex` type shall meet the
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[[thread.req.lockable.basic]]
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[*Note 1*: `unique_lock<Mutex>` meets the
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If `Mutex` meets the
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[[thread.req.lockable.req]]
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-
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requirements
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meets the
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#####
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``` cpp
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unique_lock() noexcept;
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```
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-
*
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-
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*Postconditions:* `pm == 0` and `owns == false`.
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``` cpp
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explicit unique_lock(mutex_type& m);
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```
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*
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does not own the mutex.
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*Effects:*
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`m.lock()`.
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*
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``` cpp
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unique_lock(mutex_type& m, defer_lock_t) noexcept;
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```
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*
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-
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*Postconditions:* `pm == addressof(m)` and `owns == false`.
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``` cpp
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unique_lock(mutex_type& m, try_to_lock_t);
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```
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-
*
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-
requirements
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recursive mutex the calling thread does not own the mutex.
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*Effects:*
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`m.try_lock()`.
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*
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-
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``` cpp
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unique_lock(mutex_type& m, adopt_lock_t);
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```
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*
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*
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-
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*Postconditions:* `pm == addressof(m)` and `owns == true`.
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*Throws:* Nothing.
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``` cpp
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template<class Clock, class Duration>
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unique_lock(mutex_type& m, const chrono::time_point<Clock, Duration>& abs_time);
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```
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*
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does not own the mutex. The supplied `Mutex` type
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-
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*Effects:*
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`m.try_lock_until(abs_time)`.
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*
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-
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``` cpp
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template<class Rep, class Period>
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unique_lock(mutex_type& m, const chrono::duration<Rep, Period>& rel_time);
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```
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*
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does not own the mutex. The supplied `Mutex` type
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-
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*Effects:*
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`m.try_lock_for(rel_time)`.
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*
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-
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``` cpp
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unique_lock(unique_lock&& u) noexcept;
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```
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-
*
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-
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`u.owns == false`.
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``` cpp
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unique_lock& operator=(unique_lock&& u);
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```
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*Effects:* If `owns` calls `pm->unlock()`.
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*
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-
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`u.owns == false`.
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[*Note 1*: With a recursive mutex it is possible for both `*this` and
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`u` to own the same mutex before the assignment. In this case, `*this`
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will own the mutex after the assignment and `u` will not. — *end note*]
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@@ -189,44 +177,44 @@ will own the mutex after the assignment and `u` will not. — *end note*]
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~unique_lock();
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```
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*Effects:* If `owns` calls `pm->unlock()`.
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-
#####
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``` cpp
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void lock();
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```
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*Effects:* As if by `pm->lock()`.
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*
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*Throws:* Any exception thrown by `pm->lock()`. `system_error` when an
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exception is required
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*Error conditions:*
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- `operation_not_permitted` — if `pm` is `nullptr`.
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- `resource_deadlock_would_occur` — if on entry `owns` is `true`.
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``` cpp
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bool try_lock();
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```
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*
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requirements
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*Effects:* As if by `pm->try_lock()`.
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*Returns:* The value returned by the call to `try_lock()`.
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*
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-
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*Throws:* Any exception thrown by `pm->try_lock()`. `system_error` when
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an exception is required
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*Error conditions:*
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- `operation_not_permitted` — if `pm` is `nullptr`.
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- `resource_deadlock_would_occur` — if on entry `owns` is `true`.
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@@ -234,22 +222,22 @@ an exception is required ([[thread.req.exception]]).
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``` cpp
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template<class Clock, class Duration>
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bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
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```
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*
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-
requirements
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*Effects:* As if by `pm->try_lock_until(abs_time)`.
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*Returns:* The value returned by the call to `try_lock_until(abs_time)`.
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*
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-
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*Throws:* Any exception thrown by `pm->try_lock_until()`. `system_error`
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when an exception is required
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*Error conditions:*
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- `operation_not_permitted` — if `pm` is `nullptr`.
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- `resource_deadlock_would_occur` — if on entry `owns` is `true`.
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@@ -257,22 +245,22 @@ when an exception is required ([[thread.req.exception]]).
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``` cpp
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template<class Rep, class Period>
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bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
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```
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-
*
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-
requirements
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*Effects:* As if by `pm->try_lock_for(rel_time)`.
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-
*Returns:* The value returned by the call to `
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-
*
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-
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*Throws:* Any exception thrown by `pm->try_lock_for()`. `system_error`
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when an exception is required
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*Error conditions:*
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- `operation_not_permitted` — if `pm` is `nullptr`.
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- `resource_deadlock_would_occur` — if on entry `owns` is `true`.
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@@ -281,20 +269,20 @@ when an exception is required ([[thread.req.exception]]).
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void unlock();
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```
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*Effects:* As if by `pm->unlock()`.
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*
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*Throws:* `system_error` when an exception is
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required
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*Error conditions:*
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- `operation_not_permitted` — if on entry `owns` is `false`.
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-
#####
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``` cpp
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void swap(unique_lock& u) noexcept;
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```
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@@ -304,20 +292,20 @@ void swap(unique_lock& u) noexcept;
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mutex_type* release() noexcept;
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```
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*Returns:* The previous value of `pm`.
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-
*
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``` cpp
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template<class Mutex>
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void swap(unique_lock<Mutex>& x, unique_lock<Mutex>& y) noexcept;
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```
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*Effects:* As if by `x.swap(y)`.
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-
#####
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``` cpp
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bool owns_lock() const noexcept;
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```
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private:
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mutex_type* pm; // exposition only
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bool owns; // exposition only
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};
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template<class Mutex>
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void swap(unique_lock<Mutex>& x, unique_lock<Mutex>& y) noexcept;
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}
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```
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at construction or after construction, and may be transferred, after
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acquisition, to another `unique_lock` object. Objects of type
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`unique_lock` are not copyable but are movable. The behavior of a
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program is undefined if the contained pointer `pm` is not null and the
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lockable object pointed to by `pm` does not exist for the entire
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+
remaining lifetime [[basic.life]] of the `unique_lock` object. The
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+
supplied `Mutex` type shall meet the *Cpp17BasicLockable* requirements
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+
[[thread.req.lockable.basic]].
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+
[*Note 1*: `unique_lock<Mutex>` meets the *Cpp17BasicLockable*
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+
requirements. If `Mutex` meets the *Cpp17Lockable* requirements
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+
[[thread.req.lockable.req]], `unique_lock<Mutex>` also meets the
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+
*Cpp17Lockable* requirements; if `Mutex` meets the *Cpp17TimedLockable*
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+
requirements [[thread.req.lockable.timed]], `unique_lock<Mutex>` also
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meets the *Cpp17TimedLockable* requirements. — *end note*]
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+
##### Constructors, destructor, and assignment <a id="thread.lock.unique.cons">[[thread.lock.unique.cons]]</a>
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``` cpp
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unique_lock() noexcept;
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```
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+
*Ensures:* `pm == 0` and `owns == false`.
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``` cpp
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explicit unique_lock(mutex_type& m);
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```
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+
*Preconditions:* If `mutex_type` is not a recursive mutex the calling
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+
thread does not own the mutex.
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*Effects:* Calls `m.lock()`.
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*Ensures:* `pm == addressof(m)` and `owns == true`.
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``` cpp
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unique_lock(mutex_type& m, defer_lock_t) noexcept;
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```
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+
*Ensures:* `pm == addressof(m)` and `owns == false`.
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``` cpp
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unique_lock(mutex_type& m, try_to_lock_t);
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```
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+
*Preconditions:* The supplied `Mutex` type meets the *Cpp17Lockable*
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+
requirements [[thread.req.lockable.req]]. If `mutex_type` is not a
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recursive mutex the calling thread does not own the mutex.
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+
*Effects:* Calls `m.try_lock()`.
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+
*Ensures:* `pm == addressof(m)` and `owns == res`, where `res` is the
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+
value returned by the call to `m.try_lock()`.
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``` cpp
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unique_lock(mutex_type& m, adopt_lock_t);
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```
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+
*Preconditions:* The calling thread owns the mutex.
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+
*Ensures:* `pm == addressof(m)` and `owns == true`.
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*Throws:* Nothing.
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``` cpp
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template<class Clock, class Duration>
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unique_lock(mutex_type& m, const chrono::time_point<Clock, Duration>& abs_time);
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```
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| 128 |
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| 129 |
+
*Preconditions:* If `mutex_type` is not a recursive mutex the calling
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| 130 |
+
thread does not own the mutex. The supplied `Mutex` type meets the
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| 131 |
+
*Cpp17TimedLockable* requirements [[thread.req.lockable.timed]].
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| 133 |
+
*Effects:* Calls `m.try_lock_until(abs_time)`.
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| 135 |
+
*Ensures:* `pm == addressof(m)` and `owns == res`, where `res` is the
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| 136 |
+
value returned by the call to `m.try_lock_until(abs_time)`.
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| 137 |
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| 138 |
``` cpp
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| 139 |
template<class Rep, class Period>
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| 140 |
unique_lock(mutex_type& m, const chrono::duration<Rep, Period>& rel_time);
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| 141 |
```
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| 142 |
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| 143 |
+
*Preconditions:* If `mutex_type` is not a recursive mutex the calling
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| 144 |
+
thread does not own the mutex. The supplied `Mutex` type meets the
|
| 145 |
+
*Cpp17TimedLockable* requirements [[thread.req.lockable.timed]].
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| 146 |
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| 147 |
+
*Effects:* Calls `m.try_lock_for(rel_time)`.
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|
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| 148 |
|
| 149 |
+
*Ensures:* `pm == addressof(m)` and `owns == res`, where `res` is the
|
| 150 |
+
value returned by the call to `m.try_lock_for(rel_time)`.
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| 151 |
|
| 152 |
``` cpp
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| 153 |
unique_lock(unique_lock&& u) noexcept;
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| 154 |
```
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| 155 |
|
| 156 |
+
*Ensures:* `pm == u_p.pm` and `owns == u_p.owns` (where `u_p` is the
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| 157 |
+
state of `u` just prior to this construction), `u.pm == 0` and
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| 158 |
`u.owns == false`.
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| 159 |
|
| 160 |
``` cpp
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| 161 |
unique_lock& operator=(unique_lock&& u);
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| 162 |
```
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| 163 |
|
| 164 |
*Effects:* If `owns` calls `pm->unlock()`.
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| 165 |
|
| 166 |
+
*Ensures:* `pm == u_p.pm` and `owns == u_p.owns` (where `u_p` is the
|
| 167 |
+
state of `u` just prior to this construction), `u.pm == 0` and
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| 168 |
`u.owns == false`.
|
| 169 |
|
| 170 |
[*Note 1*: With a recursive mutex it is possible for both `*this` and
|
| 171 |
`u` to own the same mutex before the assignment. In this case, `*this`
|
| 172 |
will own the mutex after the assignment and `u` will not. — *end note*]
|
|
|
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| 177 |
~unique_lock();
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| 178 |
```
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| 179 |
|
| 180 |
*Effects:* If `owns` calls `pm->unlock()`.
|
| 181 |
|
| 182 |
+
##### Locking <a id="thread.lock.unique.locking">[[thread.lock.unique.locking]]</a>
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| 183 |
|
| 184 |
``` cpp
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| 185 |
void lock();
|
| 186 |
```
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| 187 |
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| 188 |
*Effects:* As if by `pm->lock()`.
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| 189 |
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| 190 |
+
*Ensures:* `owns == true`.
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| 191 |
|
| 192 |
*Throws:* Any exception thrown by `pm->lock()`. `system_error` when an
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| 193 |
+
exception is required [[thread.req.exception]].
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| 194 |
|
| 195 |
*Error conditions:*
|
| 196 |
|
| 197 |
- `operation_not_permitted` — if `pm` is `nullptr`.
|
| 198 |
- `resource_deadlock_would_occur` — if on entry `owns` is `true`.
|
| 199 |
|
| 200 |
``` cpp
|
| 201 |
bool try_lock();
|
| 202 |
```
|
| 203 |
|
| 204 |
+
*Preconditions:* The supplied `Mutex` meets the *Cpp17Lockable*
|
| 205 |
+
requirements [[thread.req.lockable.req]].
|
| 206 |
|
| 207 |
*Effects:* As if by `pm->try_lock()`.
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| 208 |
|
| 209 |
*Returns:* The value returned by the call to `try_lock()`.
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| 210 |
|
| 211 |
+
*Ensures:* `owns == res`, where `res` is the value returned by the call
|
| 212 |
+
to `try_lock()`.
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| 213 |
|
| 214 |
*Throws:* Any exception thrown by `pm->try_lock()`. `system_error` when
|
| 215 |
+
an exception is required [[thread.req.exception]].
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| 216 |
|
| 217 |
*Error conditions:*
|
| 218 |
|
| 219 |
- `operation_not_permitted` — if `pm` is `nullptr`.
|
| 220 |
- `resource_deadlock_would_occur` — if on entry `owns` is `true`.
|
|
|
|
| 222 |
``` cpp
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| 223 |
template<class Clock, class Duration>
|
| 224 |
bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
|
| 225 |
```
|
| 226 |
|
| 227 |
+
*Preconditions:* The supplied `Mutex` type meets the
|
| 228 |
+
*Cpp17TimedLockable* requirements [[thread.req.lockable.timed]].
|
| 229 |
|
| 230 |
*Effects:* As if by `pm->try_lock_until(abs_time)`.
|
| 231 |
|
| 232 |
*Returns:* The value returned by the call to `try_lock_until(abs_time)`.
|
| 233 |
|
| 234 |
+
*Ensures:* `owns == res`, where `res` is the value returned by the call
|
| 235 |
+
to `try_lock_until(abs_time)`.
|
| 236 |
|
| 237 |
*Throws:* Any exception thrown by `pm->try_lock_until()`. `system_error`
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| 238 |
+
when an exception is required [[thread.req.exception]].
|
| 239 |
|
| 240 |
*Error conditions:*
|
| 241 |
|
| 242 |
- `operation_not_permitted` — if `pm` is `nullptr`.
|
| 243 |
- `resource_deadlock_would_occur` — if on entry `owns` is `true`.
|
|
|
|
| 245 |
``` cpp
|
| 246 |
template<class Rep, class Period>
|
| 247 |
bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
|
| 248 |
```
|
| 249 |
|
| 250 |
+
*Preconditions:* The supplied `Mutex` type meets the
|
| 251 |
+
*Cpp17TimedLockable* requirements [[thread.req.lockable.timed]].
|
| 252 |
|
| 253 |
*Effects:* As if by `pm->try_lock_for(rel_time)`.
|
| 254 |
|
| 255 |
+
*Returns:* The value returned by the call to `try_lock_for(rel_time)`.
|
| 256 |
|
| 257 |
+
*Ensures:* `owns == res`, where `res` is the value returned by the call
|
| 258 |
+
to `try_lock_for(rel_time)`.
|
| 259 |
|
| 260 |
*Throws:* Any exception thrown by `pm->try_lock_for()`. `system_error`
|
| 261 |
+
when an exception is required [[thread.req.exception]].
|
| 262 |
|
| 263 |
*Error conditions:*
|
| 264 |
|
| 265 |
- `operation_not_permitted` — if `pm` is `nullptr`.
|
| 266 |
- `resource_deadlock_would_occur` — if on entry `owns` is `true`.
|
|
|
|
| 269 |
void unlock();
|
| 270 |
```
|
| 271 |
|
| 272 |
*Effects:* As if by `pm->unlock()`.
|
| 273 |
|
| 274 |
+
*Ensures:* `owns == false`.
|
| 275 |
|
| 276 |
*Throws:* `system_error` when an exception is
|
| 277 |
+
required [[thread.req.exception]].
|
| 278 |
|
| 279 |
*Error conditions:*
|
| 280 |
|
| 281 |
- `operation_not_permitted` — if on entry `owns` is `false`.
|
| 282 |
|
| 283 |
+
##### Modifiers <a id="thread.lock.unique.mod">[[thread.lock.unique.mod]]</a>
|
| 284 |
|
| 285 |
``` cpp
|
| 286 |
void swap(unique_lock& u) noexcept;
|
| 287 |
```
|
| 288 |
|
|
|
|
| 292 |
mutex_type* release() noexcept;
|
| 293 |
```
|
| 294 |
|
| 295 |
*Returns:* The previous value of `pm`.
|
| 296 |
|
| 297 |
+
*Ensures:* `pm == 0` and `owns == false`.
|
| 298 |
|
| 299 |
``` cpp
|
| 300 |
template<class Mutex>
|
| 301 |
void swap(unique_lock<Mutex>& x, unique_lock<Mutex>& y) noexcept;
|
| 302 |
```
|
| 303 |
|
| 304 |
*Effects:* As if by `x.swap(y)`.
|
| 305 |
|
| 306 |
+
##### Observers <a id="thread.lock.unique.obs">[[thread.lock.unique.obs]]</a>
|
| 307 |
|
| 308 |
``` cpp
|
| 309 |
bool owns_lock() const noexcept;
|
| 310 |
```
|
| 311 |
|