[−][src]Trait futures_util::io::AsyncWrite
pub trait AsyncWrite { fn poll_write(
&mut self,
cx: &mut Context,
buf: &[u8]
) -> Poll<Result<usize, Error>>; fn poll_flush(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>; fn poll_close(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>; fn poll_vectored_write(
&mut self,
cx: &mut Context,
vec: &[&IoVec]
) -> Poll<Result<usize, Error>> { ... } }
Write bytes asynchronously.
This trait is analogous to the std::io::Write
trait, but integrates
with the asynchronous task system. In particular, the poll_write
method, unlike Write::write
, will automatically queue the current task
for wakeup and return if data is not yet available, rather than blocking
the calling thread.
Required Methods
fn poll_write(
&mut self,
cx: &mut Context,
buf: &[u8]
) -> Poll<Result<usize, Error>>
&mut self,
cx: &mut Context,
buf: &[u8]
) -> Poll<Result<usize, Error>>
Attempt to write bytes from buf
into the object.
On success, returns Ok(Async::Ready(num_bytes_written))
.
If the object is not ready for writing, the method returns
Ok(Async::Pending)
and arranges for the current task (via
cx.waker()
) to receive a notification when the object becomes
readable or is closed.
Implementation
This function may not return errors of kind WouldBlock
or
Interrupted
. Implementations must convert WouldBlock
into
Async::Pending
and either internally retry or convert
Interrupted
into another error kind.
fn poll_flush(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>
Attempt to flush the object, ensuring that any buffered data reach their destination.
On success, returns Ok(Async::Ready(()))
.
If flushing cannot immediately complete, this method returns
Ok(Async::Pending)
and arranges for the current task (via
cx.waker()
) to receive a notification when the object can make
progress towards flushing.
Implementation
This function may not return errors of kind WouldBlock
or
Interrupted
. Implementations must convert WouldBlock
into
Async::Pending
and either internally retry or convert
Interrupted
into another error kind.
fn poll_close(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>
Attempt to close the object.
On success, returns Ok(Async::Ready(()))
.
If closing cannot immediately complete, this function returns
Ok(Async::Pending)
and arranges for the current task (via
cx.waker()
) to receive a notification when the object can make
progress towards closing.
Implementation
This function may not return errors of kind WouldBlock
or
Interrupted
. Implementations must convert WouldBlock
into
Async::Pending
and either internally retry or convert
Interrupted
into another error kind.
Provided Methods
fn poll_vectored_write(
&mut self,
cx: &mut Context,
vec: &[&IoVec]
) -> Poll<Result<usize, Error>>
&mut self,
cx: &mut Context,
vec: &[&IoVec]
) -> Poll<Result<usize, Error>>
Attempt to write bytes from vec
into the object using vectored
IO operations.
This method is similar to poll_write
, but allows data from multiple buffers to be written
using a single operation.
On success, returns Ok(Async::Ready(num_bytes_written))
.
If the object is not ready for writing, the method returns
Ok(Async::Pending)
and arranges for the current task (via
cx.waker()
) to receive a notification when the object becomes
readable or is closed.
By default, this method delegates to using poll_write
on the first
buffer in vec
. Objects which support vectored IO should override
this method.
Implementation
This function may not return errors of kind WouldBlock
or
Interrupted
. Implementations must convert WouldBlock
into
Async::Pending
and either internally retry or convert
Interrupted
into another error kind.
Implementations on Foreign Types
impl<T> AsyncWrite for Box<T> where
T: AsyncWrite + ?Sized,
[src]
impl<T> AsyncWrite for Box<T> where
T: AsyncWrite + ?Sized,
fn poll_write(
&mut self,
cx: &mut Context,
buf: &[u8]
) -> Poll<Result<usize, Error>>
[src]
fn poll_write(
&mut self,
cx: &mut Context,
buf: &[u8]
) -> Poll<Result<usize, Error>>
fn poll_vectored_write(
&mut self,
cx: &mut Context,
vec: &[&IoVec]
) -> Poll<Result<usize, Error>>
[src]
fn poll_vectored_write(
&mut self,
cx: &mut Context,
vec: &[&IoVec]
) -> Poll<Result<usize, Error>>
fn poll_flush(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>
[src]
fn poll_flush(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>
fn poll_close(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>
[src]
fn poll_close(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>
impl AsyncWrite for Sink
[src]
impl AsyncWrite for Sink
fn poll_write(&mut self, &mut Context, buf: &[u8]) -> Poll<Result<usize, Error>>
[src]
fn poll_write(&mut self, &mut Context, buf: &[u8]) -> Poll<Result<usize, Error>>
fn poll_flush(&mut self, &mut Context) -> Poll<Result<(), Error>>
[src]
fn poll_flush(&mut self, &mut Context) -> Poll<Result<(), Error>>
fn poll_close(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>
[src]
fn poll_close(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>
fn poll_vectored_write(
&mut self,
cx: &mut Context,
vec: &[&IoVec]
) -> Poll<Result<usize, Error>>
[src]
fn poll_vectored_write(
&mut self,
cx: &mut Context,
vec: &[&IoVec]
) -> Poll<Result<usize, Error>>
impl<'a, T> AsyncWrite for &'a mut T where
T: AsyncWrite + ?Sized,
[src]
impl<'a, T> AsyncWrite for &'a mut T where
T: AsyncWrite + ?Sized,
fn poll_write(
&mut self,
cx: &mut Context,
buf: &[u8]
) -> Poll<Result<usize, Error>>
[src]
fn poll_write(
&mut self,
cx: &mut Context,
buf: &[u8]
) -> Poll<Result<usize, Error>>
fn poll_vectored_write(
&mut self,
cx: &mut Context,
vec: &[&IoVec]
) -> Poll<Result<usize, Error>>
[src]
fn poll_vectored_write(
&mut self,
cx: &mut Context,
vec: &[&IoVec]
) -> Poll<Result<usize, Error>>
fn poll_flush(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>
[src]
fn poll_flush(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>
fn poll_close(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>
[src]
fn poll_close(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>
impl<T> AsyncWrite for Cursor<T> where
T: AsMut<[u8]>,
[src]
impl<T> AsyncWrite for Cursor<T> where
T: AsMut<[u8]>,
fn poll_write(&mut self, &mut Context, buf: &[u8]) -> Poll<Result<usize, Error>>
[src]
fn poll_write(&mut self, &mut Context, buf: &[u8]) -> Poll<Result<usize, Error>>
fn poll_flush(&mut self, &mut Context) -> Poll<Result<(), Error>>
[src]
fn poll_flush(&mut self, &mut Context) -> Poll<Result<(), Error>>
fn poll_close(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>
[src]
fn poll_close(&mut self, cx: &mut Context) -> Poll<Result<(), Error>>
fn poll_vectored_write(
&mut self,
cx: &mut Context,
vec: &[&IoVec]
) -> Poll<Result<usize, Error>>
[src]
fn poll_vectored_write(
&mut self,
cx: &mut Context,
vec: &[&IoVec]
) -> Poll<Result<usize, Error>>
Implementors
impl<T> AsyncWrite for AllowStdIo<T> where
T: Write,impl<W: AsyncWrite> AsyncWrite for WriteHalf<W>