PoisonError in std::sync - Rust (original) (raw)

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

Expand description

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.

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

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

// poison the mutex
let c_mutex = Arc::clone(&mutex);
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);
    }
};

Run

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

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 = Arc::clone(&mutex);
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());

Run

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

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

Formats the value using the given formatter. Read more

Formats the value using the given formatter. Read more

👎 Deprecated since 1.42.0:

use the Display impl or to_string()

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

🔬 This is a nightly-only experimental API. (backtrace #53487)

Returns a stack backtrace, if available, of where this error occurred. Read more

👎 Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

impl Any for T where

T: 'static + ?Sized,

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

impl From for T

impl<T, U> Into for T where

U: From,

Converts the given value to a String. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.