Struct exr::io::Tracking

pub struct Tracking<T> { /* fields omitted */ }

Keep track of what byte we are at. Used to skip back to a previous place after writing some information.

Methods

impl<T> Tracking<T>

pub fn new(inner: T) -> Self

If inner is a reference, if must never be seeked directly, but only through this Tracking instance.

pub fn byte_position(&self) -> usize

Current number of bytes written or read.

impl<T: Read + Seek> Tracking<T>

pub fn seek_read_to(&mut self, target_position: usize) -> Result<()>

Set the reader to the specified byte position. If it is only a couple of bytes, no seek system call is performed.

impl<T: Write + Seek> Tracking<T>

pub fn seek_write_to(&mut self, target_position: usize) -> Result<()>

Move the writing cursor to the specified target byte index. If seeking forward, this will write zeroes.

Trait Implementations

impl<T: Debug> Debug for Tracking<T>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<T: Read> Read for Tracking<T>

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

Pull some bytes from this source into the specified buffer, returning how many bytes were read.

fn read_vectored(&mut self, bufs: &mut [IoSliceMut]) -> Result<usize, Error>

Like read, except that it reads into a slice of buffers.

unsafe fn initializer(&self) -> Initializer

🔬 This is a nightly-only experimental API. (read_initializer)

Determines if this Reader can work with buffers of uninitialized memory.

fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, Error>

Read all bytes until EOF in this source, placing them into buf.

fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>

Read all bytes until EOF in this source, appending them to buf.

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

Read the exact number of bytes required to fill buf.

Important traits for &'_ mut W

impl<'_, W> Write for &'_ mut W where
    W: Write + ?Sized, impl<'_, R> Read for &'_ mut R where
    R: Read + ?Sized, 

fn by_ref(&mut self) -> &mut Self

Creates a "by reference" adaptor for this instance of Read.

fn bytes(self) -> Bytes<Self>

Transforms this Read instance to an [Iterator] over its bytes.

Important traits for Chain<T, U>

impl<T, U> Read for Chain<T, U> where
    T: Read,
    U: Read, 

fn chain<R>(self, next: R) -> Chain<Self, R> where
    R: Read, 

Creates an adaptor which will chain this stream with another.

Important traits for Take<T>

impl<T> Read for Take<T> where
    T: Read, 

fn take(self, limit: u64) -> Take<Self>

Creates an adaptor which will read at most limit bytes from it.

impl<T: Write> Write for Tracking<T>

fn write(&mut self, buffer: &[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_vectored(&mut self, bufs: &[IoSlice]) -> Result<usize, Error>

Like write, except that it writes from a slice of buffers.

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.

Important traits for &'_ mut W

impl<'_, W> Write for &'_ mut W where
    W: Write + ?Sized, impl<'_, R> Read for &'_ mut R where
    R: Read + ?Sized, 

fn by_ref(&mut self) -> &mut Self

Creates a "by reference" adaptor for this instance of Write.