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1.0.0[][src]Struct std::thread::JoinHandle

pub struct JoinHandle<T>(_);

An owned permission to join on a thread (block on its termination).

A JoinHandle detaches the associated thread when it is dropped, which means that there is no longer any handle to thread and no way to join on it.

Due to platform restrictions, it is not possible to Clone this handle: the ability to join a thread is a uniquely-owned permission.

This struct is created by the thread::spawn function and the thread::Builder::spawn method.

Examples

Creation from thread::spawn:

use std::thread;

let join_handle: thread::JoinHandle<_> = thread::spawn(|| {
    // some work here
});Run

Creation from thread::Builder::spawn:

use std::thread;

let builder = thread::Builder::new();

let join_handle: thread::JoinHandle<_> = builder.spawn(|| {
    // some work here
}).unwrap();Run

Child being detached and outliving its parent:

use std::thread;
use std::time::Duration;

let original_thread = thread::spawn(|| {
    let _detached_thread = thread::spawn(|| {
        // Here we sleep to make sure that the first thread returns before.
        thread::sleep(Duration::from_millis(10));
        // This will be called, even though the JoinHandle is dropped.
        println!("♫ Still alive ♫");
    });
});

original_thread.join().expect("The thread being joined has panicked");
println!("Original thread is joined.");

// We make sure that the new thread has time to run, before the main
// thread returns.

thread::sleep(Duration::from_millis(1000));Run

Methods

impl<T> JoinHandle<T>[src]

pub fn thread(&self) -> &Thread[src]

Extracts a handle to the underlying thread.

Examples

use std::thread;

let builder = thread::Builder::new();

let join_handle: thread::JoinHandle<_> = builder.spawn(|| {
    // some work here
}).unwrap();

let thread = join_handle.thread();
println!("thread id: {:?}", thread.id());Run

pub fn join(self) -> Result<T>[src]

Waits for the associated thread to finish.

In terms of atomic memory orderings, the completion of the associated thread synchronizes with this function returning. In other words, all operations performed by that thread are ordered before all operations that happen after join returns.

If the child thread panics, Err is returned with the parameter given to panic.

Panics

This function may panic on some platforms if a thread attempts to join itself or otherwise may create a deadlock with joining threads.

Examples

use std::thread;

let builder = thread::Builder::new();

let join_handle: thread::JoinHandle<_> = builder.spawn(|| {
    // some work here
}).unwrap();
join_handle.join().expect("Couldn't join on the associated thread");Run

Trait Implementations

impl<T> JoinHandleExt for JoinHandle<T>
1.9.0
[src]

impl<T> AsRawHandle for JoinHandle<T>
1.9.0
[src]

impl<T> IntoRawHandle for JoinHandle<T>
1.9.0
[src]

impl<T> Debug for JoinHandle<T>
1.16.0
[src]

impl<T> Send for JoinHandle<T>
1.29.0
[src]

impl<T> Sync for JoinHandle<T>
1.29.0
[src]

Blanket Implementations

impl<T> From for T[src]

impl<T, U> TryFrom for T where
    U: Into<T>, 
[src]

type Error = Infallible

The type returned in the event of a conversion error.

impl<T, U> TryInto for T where
    U: TryFrom<T>, 
[src]

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.

impl<T, U> Into for T where
    U: From<T>, 
[src]

impl<T> Borrow for T where
    T: ?Sized
[src]

impl<T> BorrowMut for T where
    T: ?Sized
[src]

impl<T> Any for T where
    T: 'static + ?Sized
[src]