std::execution::ensure_started

 

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Execution concepts scheduler receiver receiver_of operation_state    sender sender_in sender_to Execution components Execution contexts run_loop Execution domains default_domain Forward progress guarantee forward_progress_guarantee Environments empty_env    get_env    env_of_t Queries std::stop_token_of_t std::get_stop_token std::get_allocator std::forwarding_query get_scheduler get_domain get_forward_progress_guarantee get_delegation_scheduler get_completion_scheduler Completion signatures completion_signatures completion_signatures_of_t transform_completion_signatures transform_completion_signatures_of    value_types_of_t error_types_of_t    tag_of_t sends_stopped    Sender adaptor closures sender_adaptor_closure Coroutine utility as_awaitable with_awaitable_senders

Core operations Operation state connect connect_result_t start Completion set_value set_error set_stopped Transformation transform_env transform_sender apply_sender Sender algorithms Sender factories just just_error just_stopped read_env schedule schedule_result_t Sender adaptors starts_on continues_on    on then upon_error upon_stopped let_value let_error let_stopped schedule_from when_all when_all_with_variant into_variant stopped_as_optional stopped_as_error bulk split Sender consumers this_thread::sync_wait this_thread::sync_wait_with_variant

 

Defined in header <execution>
execution::sender auto ensure_started( execution::sender auto sender );		(since C++26)

Parameters

sender

-

input sender of which the stopped channel is mapped into err

Return value

Returns a sender which completes when the provided sender completes and sends values equivalent to those of the provided sender.

Notes

• Once ensure_started returns, it is known that the provided sender has been connected and start has been called on the resulting operation state. In other words, the work described by the provided sender has been submitted for execution on the appropriate execution resources.

• If the returned sender is destroyed before execution::connect() is called, or if execution::connect() is called but the returned operation-state is destroyed before execution::start() is called, then a stop-request is sent to the eagerly launched operation and the operation is detached and will run to completion in the background.

• In such a case, the operation's result will be discarded when it is eventually complete.

• Note that the application will need to make sure that resources are kept alive in the case that the operation detaches (e.g. by holding a std::shared_ptr to those resources).