TimedLockable

Timed lockable type

A timed lockable type is a Lockable type that supports try_lock_for and try_lock_until.

The standard library defines the following TimedLockable types:

header	type
`timed_mutex`
`recursive_timed_mutex`

A value m is of a TimedLockable type if the following expressions are well-formed:

m.lock()

Effects: Block until a lock can be acquired for the current execution agent. If an exception is thrown, then a lock shall not have been acquired for the current execution agent.

m.unlock()

m.try_lock()

Effects: Attempts to acquire a lock for the current execution agent without blocking. If an exception is thrown, then a lock shall not have been acquired for the current execution agent.
Return type: bool
Returns: true if the lock was acquired, false otherwise.

m.try_lock_for(rel_time)

Effects: Attempts to acquire a lock for the current execution agent within the relative timeout specified by rel_time. The function shall not return within the timeout specified by rel_time unless it has obtained a lock on m for the current execution agent. If an exception is thrown then a lock shall not have been acquired for the current execution agent.
Return type: bool
Returns: true if the lock was acquired, false otherwise.

m.try_lock_until(abs_time)

Effects: Attempts to acquire a lock for the current execution agent before the absolute timeout specified by abs_time. The function shall not return before the timeout specified by abs_time unless it has obtained a lock on m for the current execution agent. If an exception is thrown then a lock shall not have been acquired for the current execution agent.
Return type: bool
Returns: true if the lock was acquired, false otherwise.

Where:

value	description
`m`	A `TimedLockable` type
`rel_time`	A value of an instantiation of `duration`
`abs_time`	A value of an instantiation of `time_point`