std::stop_source:: request_stop

bool request_stop ( ) noexcept ;		(since C++20)

Issues a stop request to the stop-state, if the stop_source object has a stop-state and it has not yet already had stop requested.

The determination is made atomically, and if stop was requested, the stop-state is atomically updated to avoid race conditions, such that:

• stop_requested ( ) and stop_possible ( ) can be concurrently invoked on other stop_token s and stop_source s of the same stop-state;
• request_stop ( ) can be concurrently invoked on other stop_source objects, and only one will actually perform the stop request.

However, see the Notes section.

Parameters

(none)

Return value

true if the stop_source object has a stop-state and this invocation made a stop request, otherwise false .

Postconditions

stop_possible ( ) is false or stop_requested ( ) is true .

Notes

If the request_stop ( ) does issue a stop request (i.e., returns true ), then any stop_callback s registered for the same associated stop-state will be invoked synchronously, on the same thread request_stop ( ) is issued on. If an invocation of a callback exits via an exception, std::terminate is called.

If the stop_source object has a stop-state but a stop request has already been made, this function returns false . However there is no guarantee that another stop_source object which has just (successfully) requested stop is not still in the middle of invoking a stop_callback function.

If the request_stop ( ) does issue a stop request (i.e., returns true ), then all condition variables of base type std::condition_variable_any registered with an interruptible wait for stop_token s associated with the stop_source 's stop-state will be notified.

Example

This section is incomplete Reason: no example