What should be noted when using async in C++?

When using the async function in C++, the following points should be kept in mind:

1. The return value of an asynchronous task should be a std::future object, and the result of the asynchronous task can be obtained by calling the get() method.
2. If an asynchronous task needs to be delayed, you can use the std::launch::deferred parameter to delay the execution of the task.
3. To avoid data race when using shared resources in asynchronous tasks, it is recommended to use synchronization mechanisms such as std::mutex to protect the shared resources.
4. Exceptions in asynchronous tasks should be managed using try-catch blocks to prevent the program from crashing.
5. When creating asynchronous tasks with std::async, it is important to consider the task’s scheduling method, which can be specified with the std::launch::async parameter to execute the task immediately.
6. For cases where multiple asynchronous tasks need to be waited for completion, you can use the std::future::wait_for() or std::future::wait_until() methods to wait for the tasks to finish.
7. To cancel asynchronous tasks, you can utilize the std::future::cancel() method.
8. Asynchronously tasks created using std::async will be automatically destroyed when the program exits, eliminating the need to manually manage resources.