pub struct Aio<E> { /* private fields */ }net only.Expand description
Associates a POSIX AIO control block with the reactor that drives it.
Aio’s wrapped type must implement AioSource to be driven
by the reactor.
The wrapped source may be accessed through the Aio via the Deref and
DerefMut traits.
§Clearing readiness
If Aio::poll_ready returns ready, but the consumer determines that the
Source is not completely ready and must return to the Pending state,
Aio::clear_ready may be used. This can be useful with
lio_listio, which may generate a kevent when only a portion of the
operations have completed.
§Platforms
Only FreeBSD implements POSIX AIO with kqueue notification, so
Aio is only available for that operating system.
Implementations§
Source§impl<E: AioSource> Aio<E>
impl<E: AioSource> Aio<E>
Sourcepub fn new_for_aio(io: E) -> Result<Self>
pub fn new_for_aio(io: E) -> Result<Self>
Creates a new Aio suitable for use with POSIX AIO functions.
It will be associated with the default reactor. The runtime is usually
set implicitly when this function is called from a future driven by a
Tokio runtime, otherwise runtime can be set explicitly with
Runtime::enter function.
Sourcepub fn new_for_lio(io: E) -> Result<Self>
pub fn new_for_lio(io: E) -> Result<Self>
Creates a new Aio suitable for use with lio_listio.
It will be associated with the default reactor. The runtime is usually
set implicitly when this function is called from a future driven by a
Tokio runtime, otherwise runtime can be set explicitly with
Runtime::enter function.
Sourcepub fn clear_ready(&self, ev: AioEvent)
pub fn clear_ready(&self, ev: AioEvent)
Indicates to Tokio that the source is no longer ready. The internal readiness flag will be cleared, and tokio will wait for the next edge-triggered readiness notification from the OS.
It is critical that this method not be called unless your code
actually observes that the source is not ready. The OS must
deliver a subsequent notification, or this source will block
forever. It is equally critical that you do call this method if you
resubmit the same structure to the kernel and poll it again.
This method is not very useful with AIO readiness, since each aiocb
structure is typically only used once. It’s main use with
lio_listio, which will sometimes send notification when only a
portion of its elements are complete. In that case, the caller must
call clear_ready before resubmitting it.
Sourcepub fn into_inner(self) -> E
pub fn into_inner(self) -> E
Destroy the Aio and return its inner source.
Sourcepub fn poll_ready(&self, cx: &mut Context<'_>) -> Poll<Result<AioEvent>>
pub fn poll_ready(&self, cx: &mut Context<'_>) -> Poll<Result<AioEvent>>
Polls for readiness. Either AIO or LIO counts.
This method returns:
Poll::Pendingif the underlying operation is not complete, whether or not it completed successfully. This will be true if the OS is still processing it, or if it has not yet been submitted to the OS.Poll::Ready(Ok(_))if the underlying operation is complete.Poll::Ready(Err(_))if the reactor has been shutdown. This does not indicate that the underlying operation encountered an error.
When the method returns Poll::Pending, the Waker in the provided Context
is scheduled to receive a wakeup when the underlying operation
completes. Note that on multiple calls to poll_ready, only the Waker from the
Context passed to the most recent call is scheduled to receive a wakeup.
Trait Implementations§
Auto Trait Implementations§
impl<E> Freeze for Aio<E>where
E: Freeze,
impl<E> !RefUnwindSafe for Aio<E>
impl<E> Send for Aio<E>where
E: Send,
impl<E> Sync for Aio<E>where
E: Sync,
impl<E> Unpin for Aio<E>where
E: Unpin,
impl<E> !UnwindSafe for Aio<E>
Blanket Implementations§
Source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
Source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Layout§
Note: Unable to compute type layout, possibly due to this type having generic parameters. Layout can only be computed for concrete, fully-instantiated types.