Struct JoinHandle 

pub struct JoinHandle<T> { /* private fields */ }

A native local task handle. It is neither Send nor Sync.

Returned by crate::rt::spawn() and crate::rt::Runtime::spawn(). Dropping the handle detaches the task unless cancel_on_drop is enabled. Awaiting it yields the task’s output, or an error if no output is available, for example after cancellation, a task panic, or runtime shutdown.

Implementations

impl<T> JoinHandle<T>

pub fn cancel_on_drop(self) -> Self

Requests cancellation when this handle is dropped instead of detaching the task.

Cancellation follows cancel and does not wait for cleanup. A running poll is not interrupted. The deprecated detach method still overrides this setting.

pub fn cancel(self)

Requests cancellation and discards the result without waiting for cleanup.

The future is dropped when the runtime next processes the task, or during runtime shutdown. A running poll is not interrupted.

pub fn detach(self)

👎Deprecated since 4.5.0:

Drop the handle instead if cancel_on_drop() is not enabled

Detaches the task so it continues running independently.

Overrides cancel_on_drop without requesting cancellation.

pub fn is_finished(&self) -> bool

Returns true if the task completed or was closed without an output.

Trait Implementations

impl<T: Debug> Debug for JoinHandle<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T> Future for JoinHandle<T>

type Output = Result<T, JoinError>

The type of value produced on completion.

fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output>

Attempts to resolve the future to a final value, registering the current task for wakeup if the value is not yet available.