Struct io::Writer

pub struct Writer<W>(_);

A stateful writer that keeps track of its current offset within the internal stateless ByteWriter I/O stream.

This implements the [core2::io::Write] trait for write-only access, as well as the [core2::io::Seek] trait if the underlying I/O stream implements KnownLength. It also forwards all other write-only I/O-related traits implemented by the underlying I/O stream.

Note: this is implemented as a thin wrapper around ReaderWriter.

Implementations

impl<W: ByteWriter> Writer<W>

pub fn new(writer: W) -> Self

Creates a new Writer with an initial offset of 0.

Trait Implementations

impl<IO> BlockIo for Writer<IO>where IO: BlockIo,

fn block_size(&self) -> usize

Returns the size in bytes of a single block (i.e., sector), the minimum granularity of I/O transfers.

impl<IO> BlockWriter for Writer<IO>where IO: BlockWriter,

fn write_blocks( &mut self, buffer: &[u8], block_offset: usize ) -> Result<usize, IoError>

Writes blocks of data from the given buffer to this writer.

fn flush(&mut self) -> Result<(), IoError>

Flushes this entire writer’s output stream, ensuring all contents in intermediate buffers are fully written out.

impl<IO> ByteWriter for Writer<IO>where IO: ByteWriter,

fn write_at(&mut self, buffer: &[u8], offset: usize) -> Result<usize, IoError>

Writes bytes of data from the given buffer to this writer.

fn flush(&mut self) -> Result<(), IoError>

Flushes this writer’s output stream, ensuring all contents in intermediate buffers are fully written out.

impl<IO> KnownLength for Writer<IO>where IO: KnownLength,

fn len(&self) -> usize

Returns the length (size in bytes) of this I/O stream or device.

impl<IO> Seek for Writer<IO>where IO: KnownLength,

fn seek(&mut self, position: SeekFrom) -> Result<u64>

Seek to an offset, in bytes, in a stream.

fn rewind(&mut self) -> Result<(), Error>

Rewind to the beginning of a stream.

fn stream_len(&mut self) -> Result<u64, Error>

Returns the length of this stream (in bytes).

fn stream_position(&mut self) -> Result<u64, Error>

Returns the current seek position from the start of the stream.

impl<IO> Write for Writer<IO>where IO: ByteWriter,

fn write(&mut self, buf: &[u8]) -> Result<usize>

Write a buffer into this writer, returning how many bytes were written.

fn flush(&mut self) -> Result<()>

Flush this output stream, ensuring that all intermediately buffered contents reach their destination.

fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>

Attempts to write an entire buffer into this writer.

fn write_fmt(&mut self, fmt: Arguments<'_>) -> Result<(), Error>

Writes a formatted string into this writer, returning any error encountered.

fn by_ref(&mut self) -> &mut Selfwhere Self: Sized,

Creates a “by reference” adaptor for this instance of Write.