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The
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:
ExpressionPreconditionsEffectsReturn 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.
Shared locks
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.
Standard library
The following standard library types satisfy SharedLockable requirements:
See also