RawWaker in core::task - Rust (original) (raw)
Struct RawWaker
1.36.0 · Source
pub struct RawWaker { /* private fields */ }Expand description
A RawWaker allows the implementor of a task executor to create a Wakeror a LocalWaker which provides customized wakeup behavior.
It consists of a data pointer and a virtual function pointer table (vtable)that customizes the behavior of the RawWaker.
RawWakers are unsafe to use. Implementing the Wake trait is a safe alternative that requires memory allocation.
1.36.0 (const: 1.36.0) · Source
Creates a new RawWaker from the provided data pointer and vtable.
The data pointer can be used to store arbitrary data as required by the executor. This could be e.g. a type-erased pointer to an Arcthat is associated with the task. The value of this pointer will get passed to all functions that are part of the vtable as the first parameter.
It is important to consider that the data pointer must point to a thread safe type such as an Arc<T: Send + Sync>when used to construct a Waker. This restriction is lifted when constructing a LocalWaker, which allows using types that do not implement[Send](../marker/trait.Send.html "trait core:📑:Send") + [Sync](../marker/trait.Sync.html "trait core:📑:Sync") like Rc<T>.
The vtable customizes the behavior of a Waker which gets created from a RawWaker. For each operation on the Waker, the associated function in the vtable of the underlying RawWaker will be called.
Tests for self and other values to be equal, and is used by ==.
Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.