Struct Thread

1.0.0 · Source

pub struct Thread { /* private fields */ }

Available on crate features std only.

Expand description

🧵 🫆 std A handle to a thread.

^📍^work/thread ^{re-exported from std::thread}

Implementations§

Source §

impl Thread

1.0.0 · Source

pub fn unpark(&self)

Atomically makes the handle’s token available if it is not already.

Every thread is equipped with some basic low-level blocking support, via the park function and the unpark() method. These can be used as a more CPU-efficient implementation of a spinlock.

See the park documentation for more details.

§Examples

use std::thread;
use std::time::Duration;
use std::sync::atomic::{AtomicBool, Ordering};

static QUEUED: AtomicBool = AtomicBool::new(false);

let parked_thread = thread::Builder::new()
    .spawn(|| {
        println!("Parking thread");
        QUEUED.store(true, Ordering::Release);
        thread::park();
        println!("Thread unparked");
    })
    .unwrap();

// Let some time pass for the thread to be spawned.
thread::sleep(Duration::from_millis(10));

// Wait until the other thread is queued.
// This is crucial! It guarantees that the `unpark` below is not consumed
// by some other code in the parked thread (e.g. inside `println!`).
while !QUEUED.load(Ordering::Acquire) {
    // Spinning is of course inefficient; in practice, this would more likely be
    // a dequeue where we have no work to do if there's nobody queued.
    std::hint::spin_loop();
}

println!("Unpark the thread");
parked_thread.thread().unpark();

parked_thread.join().unwrap();

1.19.0 · Source

pub fn id(&self) -> ThreadId

Gets the thread’s unique identifier.

§Examples

use std::thread;

let other_thread = thread::spawn(|| {
    thread::current().id()
});

let other_thread_id = other_thread.join().unwrap();
assert!(thread::current().id() != other_thread_id);

1.0.0 · Source

pub fn name(&self) -> Option<&str> ⓘ

Gets the thread’s name.

For more information about named threads, see this module-level documentation.

§Examples

Threads by default have no name specified:

use std::thread;

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

let handler = builder.spawn(|| {
    assert!(thread::current().name().is_none());
}).unwrap();

handler.join().unwrap();

Thread with a specified name:

use std::thread;

let builder = thread::Builder::new()
    .name("foo".into());

let handler = builder.spawn(|| {
    assert_eq!(thread::current().name(), Some("foo"))
}).unwrap();

handler.join().unwrap();

Source

pub fn into_raw(self) -> *const ()

🔬This is a nightly-only experimental API. (thread_raw)

Consumes the Thread, returning a raw pointer.

To avoid a memory leak the pointer must be converted back into a Thread using Thread::from_raw. The pointer is guaranteed to be aligned to at least 8 bytes.

§Examples

#![feature(thread_raw)]

use std::thread::{self, Thread};

let thread = thread::current();
let id = thread.id();
let ptr = Thread::into_raw(thread);
unsafe {
    assert_eq!(Thread::from_raw(ptr).id(), id);
}

Source