Struct tokio::sync::OwnedMutexGuard [−][src]
pub struct OwnedMutexGuard<T: ?Sized> { /* fields omitted */ }Expand description
An owned handle to a held Mutex.
This guard is only available from a Mutex that is wrapped in an Arc. It
is identical to MutexGuard, except that rather than borrowing the Mutex,
it clones the Arc, incrementing the reference count. This means that
unlike MutexGuard, it will have the 'static lifetime.
As long as you have this guard, you have exclusive access to the underlying
T. The guard internally keeps a reference-counted pointer to the original
Mutex, so even if the lock goes away, the guard remains valid.
The lock is automatically released whenever the guard is dropped, at which
point lock will succeed yet again.
Implementations
Returns a reference to the original Arc<Mutex>.
use std::sync::Arc;
use tokio::sync::{Mutex, OwnedMutexGuard};
async fn unlock_and_relock(guard: OwnedMutexGuard<u32>) -> OwnedMutexGuard<u32> {
println!("1. contains: {:?}", *guard);
let mutex: Arc<Mutex<u32>> = OwnedMutexGuard::mutex(&guard).clone();
drop(guard);
let guard = mutex.lock_owned().await;
println!("2. contains: {:?}", *guard);
guard
}