...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
An initiating function is a function which may be called to start an asynchronous operation. A completion handler is a function object that will be invoked, at most once, with the result of the asynchronous operation.
The lifecycle of an asynchronous operation is comprised of the following events and phases:
— Event 1: The asynchronous operation is started by a call to the initiating function.
— Phase 1: The asynchronous operation is now outstanding.
— Event 2: The externally observable side effects of the asynchronous operation, if any, are fully established. The completion handler is submitted to an executor.
— Phase 2: The asynchronous operation is now completed.
— Event 3: The completion handler is called with the result of the asynchronous operation.
In this library, all functions with the prefix async_
are
initiating functions.