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/Rust

Struct std::sync::PoisonError

pub struct PoisonError<T> { /* fields omitted */ }

A type of error which can be returned whenever a lock is acquired.

Both Mutexes and RwLocks are poisoned whenever a thread fails while the lock is held. The precise semantics for when a lock is poisoned is documented on each lock, but once a lock is poisoned then all future acquisitions will return this error.

Examples

use std::sync::{Arc, Mutex};
use std::thread;

let mutex = Arc::new(Mutex::new(1));

// poison the mutex
let c_mutex = mutex.clone();
let _ = thread::spawn(move || {
    let mut data = c_mutex.lock().unwrap();
    *data = 2;
    panic!();
}).join();

match mutex.lock() {
    Ok(_) => unreachable!(),
    Err(p_err) => {
        let data = p_err.get_ref();
        println!("recovered: {}", data);
    }
};

Methods

impl<T> PoisonError<T>[src]

pub fn new(guard: T) -> PoisonError<T>[src]1.2.0

Creates a PoisonError.

This is generally created by methods like Mutex::lock or RwLock::read.

pub fn into_inner(self) -> T[src]1.2.0

Consumes this error indicating that a lock is poisoned, returning the underlying guard to allow access regardless.

Examples

use std::collections::HashSet;
use std::sync::{Arc, Mutex};
use std::thread;

let mutex = Arc::new(Mutex::new(HashSet::new()));

// poison the mutex
let c_mutex = mutex.clone();
let _ = thread::spawn(move || {
    let mut data = c_mutex.lock().unwrap();
    data.insert(10);
    panic!();
}).join();

let p_err = mutex.lock().unwrap_err();
let data = p_err.into_inner();
println!("recovered {} items", data.len());

pub fn get_ref(&self) -> &T[src]1.2.0

ⓘImportant traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
    F: Unpin + Future + ?Sized, 
    type Output = <F as Future>::Output;
impl<'_, I> Iterator for &'_ mut I where
    I: Iterator + ?Sized, 
    type Item = <I as Iterator>::Item;
impl<'_, R: Read + ?Sized> Read for &'_ mut R
impl<'_, W: Write + ?Sized> Write for &'_ mut W

Reaches into this error indicating that a lock is poisoned, returning a reference to the underlying guard to allow access regardless.

pub fn get_mut(&mut self) -> &mut T[src]1.2.0

ⓘImportant traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
    F: Unpin + Future + ?Sized, 
    type Output = <F as Future>::Output;
impl<'_, I> Iterator for &'_ mut I where
    I: Iterator + ?Sized, 
    type Item = <I as Iterator>::Item;
impl<'_, R: Read + ?Sized> Read for &'_ mut R
impl<'_, W: Write + ?Sized> Write for &'_ mut W

Reaches into this error indicating that a lock is poisoned, returning a mutable reference to the underlying guard to allow access regardless.

Trait Implementations

impl<T> Error for PoisonError<T>[src]

fn cause(&self) -> Option<&dyn Error>[src]

Deprecated since 1.33.0: replaced by Error::source, which can support downcasting

The lower-level cause of this error, if any. Read more

fn source(&self) -> Option<&(dyn Error + 'static)>[src]1.30.0

The lower-level source of this error, if any. Read more

impl<T> Display for PoisonError<T>[src]

impl<T> Debug for PoisonError<T>[src]

impl<T> From<PoisonError<T>> for TryLockError<T>[src]

Auto Trait Implementations

impl<T> UnwindSafe for PoisonError<T> where
    T: UnwindSafe

impl<T> RefUnwindSafe for PoisonError<T> where
    T: RefUnwindSafe

impl<T> Unpin for PoisonError<T> where
    T: Unpin

impl<T> Send for PoisonError<T> where
    T: Send

impl<T> Sync for PoisonError<T> where
    T: Sync

Blanket Implementations

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

type Error = Infallible

The type returned in the event of a conversion error.

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

impl<T> From<T> for T[src]

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

ⓘImportant traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
    F: Unpin + Future + ?Sized, 
    type Output = <F as Future>::Output;
impl<'_, I> Iterator for &'_ mut I where
    I: Iterator + ?Sized, 
    type Item = <I as Iterator>::Item;
impl<'_, R: Read + ?Sized> Read for &'_ mut R
impl<'_, W: Write + ?Sized> Write for &'_ mut W

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

ⓘImportant traits for &'_ mut F
impl<'_, F> Future for &'_ mut F where
    F: Unpin + Future + ?Sized, 
    type Output = <F as Future>::Output;
impl<'_, I> Iterator for &'_ mut I where
    I: Iterator + ?Sized, 
    type Item = <I as Iterator>::Item;
impl<'_, R: Read + ?Sized> Read for &'_ mut R
impl<'_, W: Write + ?Sized> Write for &'_ mut W

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

impl<T> ToString for T where
    T: Display + ?Sized
[src]

© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/std/sync/struct.PoisonError.html