[][src]Struct tokio::io::BufWriter

pub struct BufWriter<W> { /* fields omitted */ }
This is supported on feature="io-util" only.

Wraps a writer and buffers its output.

It can be excessively inefficient to work directly with something that implements AsyncWrite. A BufWriter keeps an in-memory buffer of data and writes it to an underlying writer in large, infrequent batches.

BufWriter can improve the speed of programs that make small and repeated write calls to the same file or network socket. It does not help when writing very large amounts at once, or writing just one or a few times. It also provides no advantage when writing to a destination that is in memory, like a Vec<u8>.

When the BufWriter is dropped, the contents of its buffer will be discarded. Creating multiple instances of a BufWriter on the same stream can cause data loss. If you need to write out the contents of its buffer, you must manually call flush before the writer is dropped.

Implementations

impl<W: AsyncWrite> BufWriter<W>[src]

pub fn new(inner: W) -> Self[src]

This is supported on feature="io-util" only.

Creates a new BufWriter with a default buffer capacity. The default is currently 8 KB, but may change in the future.

pub fn with_capacity(cap: usize, inner: W) -> Self[src]

This is supported on feature="io-util" only.

Creates a new BufWriter with the specified buffer capacity.

pub fn get_ref(&self) -> &W

Important traits for &'_ mut F

impl<'_, F> Future for &'_ mut F where
    F: Unpin + Future + ?Sized
type Output = <F as Future>::Output;
[src]

This is supported on feature="io-util" only.

Gets a reference to the underlying writer.

pub fn get_mut(&mut self) -> &mut W

Important traits for &'_ mut F

impl<'_, F> Future for &'_ mut F where
    F: Unpin + Future + ?Sized
type Output = <F as Future>::Output;
[src]

This is supported on feature="io-util" only.

Gets a mutable reference to the underlying writer.

It is inadvisable to directly write to the underlying writer.

pub fn get_pin_mut(self: Pin<&mut Self>) -> Pin<&mut W>

Important traits for Pin<P>

impl<P> Future for Pin<P> where
    P: Unpin + DerefMut,
    <P as Deref>::Target: Future
type Output = <<P as Deref>::Target as Future>::Output;
[src]

This is supported on feature="io-util" only.

Gets a pinned mutable reference to the underlying writer.

It is inadvisable to directly write to the underlying writer.

pub fn into_inner(self) -> W[src]

This is supported on feature="io-util" only.

Consumes this BufWriter, returning the underlying writer.

Note that any leftover data in the internal buffer is lost.

pub fn buffer(&self) -> &[u8][src]

This is supported on feature="io-util" only.

Returns a reference to the internally buffered data.

Trait Implementations

impl<W: AsyncWrite + AsyncBufRead> AsyncBufRead for BufWriter<W>[src]

impl<W: AsyncWrite + AsyncRead> AsyncRead for BufWriter<W>[src]

impl<W: AsyncWrite> AsyncWrite for BufWriter<W>[src]

impl<W: Debug> Debug for BufWriter<W>[src]

impl<RW> From<BufWriter<BufReader<RW>>> for BufStream<RW>[src]

impl<'__pin, W> Unpin for BufWriter<W> where
    __Origin<'__pin, W>: Unpin
[src]

Auto Trait Implementations

impl<W> RefUnwindSafe for BufWriter<W> where
    W: RefUnwindSafe

impl<W> Send for BufWriter<W> where
    W: Send

impl<W> Sync for BufWriter<W> where
    W: Sync

impl<W> UnwindSafe for BufWriter<W> where
    W: UnwindSafe

Blanket Implementations

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

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

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

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

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

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> 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.