C++ named requirements: SharedLockable (since C++14)
From cppreference.com
The SharedLockable requirements describe the minimal characteristics of types that provide shared blocking semantics for execution agents (i.e. threads).
Requirements
For type L to be SharedLockable, the following conditions have to be satisfied for an object m of type L:
| Expression | Preconditions | Effects | Return value |
|---|---|---|---|
| m.lock_shared() | Blocks until a lock can be obtained for the current execution agent (thread, process, task). If an exception is thrown, no lock is obtained. | ||
| m.try_lock_shared() | Attempts to obtain a lock for the current execution agent (thread, process, task) without blocking. If an exception is thrown, no lock is obtained. | true if the lock was obtained, false otherwise | |
| m.unlock_shared() | The current execution agent holds a shared lock on m.
|
Releases the shared lock held by the execution agent.
Throws no exceptions. |
A lock on an object is said to be shared lock if it is acquired by a call to lock_shared, try_lock_shared, try_lock_shared_for, or try_lock_shared_until member function.