Mar 12, 2024 · The class template std::future provides a mechanism to access the result of asynchronous operations: An asynchronous operation (created via std::async, std::packaged_task, …

Aug 27, 2021 · Checks if the future refers to a shared state. This is the case only for futures that were not default-constructed or moved from (i.e. returned by std::promise::get_future (), …

Feb 22, 2024 · The get member function waits (by calling wait ()) until the shared state is ready, then retrieves the value stored in the shared state (if any). Right after calling this function, valid () is false. …

Mar 19, 2025 · Specifies state of a future as returned by wait_for and wait_until functions of std::future and std::shared_future. Constants

Jul 21, 2020 · A future represents the result of an asynchronous operation, and can have two states: uncompleted or completed. Most likely, as you aren't doing this just for fun, you actually need the …

Aug 27, 2021 · If the future is the result of a call to std::async that used lazy evaluation, this function returns immediately without waiting. This function may block for longer than timeout_duration due to …

Nov 27, 2023 · future (const future &) = delete; ~future (); future & operator =(const future &) = delete; future & operator =(future &&) noexcept; shared_future <R> share () noexcept; // retrieving the value …

Aug 2, 2020 · wait_until waits for a result to become available. It blocks until specified timeout_time has been reached or the result becomes available, whichever comes first. The return value indicates why …

But you might want to have a queue of completed jobs to check, instead of a single future. This queue would only be consumed by your main thread and can be implemented with a non-blocking thread …

Oct 23, 2023 · The promise is the "push" end of the promise-future communication channel: the operation that stores a value in the shared state synchronizes-with (as defined in std::memory_order) …