[][src]Struct sgx_tstd::io::BufWriter

pub struct BufWriter<W: Write> { /* fields omitted */ }

Wraps a writer and buffers its output.

It can be excessively inefficient to work directly with something that implements Write. For example, every call to write on TcpStream results in a system call. A BufWriter<W> keeps an in-memory buffer of data and writes it to an underlying writer in large, infrequent batches.

BufWriter<W> 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>.

It is critical to call flush before BufWriter<W> is dropped. Though dropping will attempt to flush the the contents of the buffer, any errors that happen in the process of dropping will be ignored. Calling flush ensures that the buffer is empty and thus dropping will not even attempt file operations.

By wrapping the stream with a BufWriter<W>, these ten writes are all grouped together by the buffer and will all be written out in one system call when the stream is flushed.


impl<W: Write> BufWriter<W>[src]

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

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

pub fn with_capacity(capacity: usize, inner: W) -> BufWriter<W>[src]

Creates a new BufWriter<W> with the specified buffer capacity.

pub fn get_ref(&self) -> &W[src]

Gets a reference to the underlying writer.

pub fn get_mut(&mut self) -> &mut W[src]

Gets a mutable reference to the underlying writer.

It is inadvisable to directly write to the underlying writer.

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

Returns a reference to the internally buffered data.

pub fn capacity(&self) -> usize[src]

Returns the number of bytes the internal buffer can hold without flushing.

pub fn into_inner(self) -> Result<W, IntoInnerError<BufWriter<W>>>[src]

Unwraps this BufWriter<W>, returning the underlying writer.

The buffer is written out before returning the writer.


An Err will be returned if an error occurs while flushing the buffer.

Trait Implementations

impl<W: Write> Debug for BufWriter<W> where
    W: Debug

impl<W: Write> Drop for BufWriter<W>[src]

impl<W: Write + Seek> Seek for BufWriter<W>[src]

fn seek(&mut self, pos: SeekFrom) -> Result<u64>[src]

Seek to the offset, in bytes, in the underlying writer.

Seeking always writes out the internal buffer before seeking.

impl<W: Write> Write for BufWriter<W>[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> Unpin for BufWriter<W> where
    W: Unpin

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

Blanket Implementations

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

impl<T> Borrow<T> for T where
    T: ?Sized

impl<T> BorrowMut<T> for T where
    T: ?Sized

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

impl<T, U> Into<U> for T where
    U: From<T>, 

impl<T, U> TryFrom<U> for T where
    U: Into<T>, 

type Error = Infallible

The type returned in the event of a conversion error.

impl<T, U> TryInto<U> for T where
    U: TryFrom<T>, 

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.