std::io::Take - Rust
Description: API documentation for the Rust `Take` struct in crate `std`.
Keywords: rust, rustlang, rust-lang, Take

# Struct std::io::Take 1.0.0 [−] [src]

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

Reader adaptor which limits the bytes read from an underlying reader.

This struct is generally created by calling `take` on a reader. Please see the documentation of `take` for more details.

## Methods

### `impl<T> Take<T>`
[src]

#### `fn limit(&self) -> u64`
[src]

Returns the number of bytes that can be read before this instance will return EOF.

# Note

This instance may reach `EOF` after reading fewer bytes than indicated by this method if the underlying `Read` instance reaches EOF.

# Examples

    use std::io;
    use std::io::prelude::*;
    use std::fs::File;

    let f = File::open("foo.txt")?;

    // read at most five bytes
    let handle = f.take(5);

    println!("limit: {}", handle.limit());Run

#### `fn set_limit(&mut self, limit: u64)`
[src]

🔬 This is a nightly-only experimental API. (`take_set_limit` #42781)

Sets the number of bytes that can be read before this instance will return EOF. This is the same as constructing a new `Take` instance, so the amount of bytes read and the previous limit value don't matter when calling this method.

# Examples

    #![feature(take_set_limit)]
    use std::io;
    use std::io::prelude::*;
    use std::fs::File;

    let f = File::open("foo.txt")?;

    // read at most five bytes
    let mut handle = f.take(5);
    handle.set_limit(10);

    assert_eq!(handle.limit(), 10);Run

#### `fn into_inner(self) -> T`
1.15.0
[src]

Consumes the `Take`, returning the wrapped reader.

# Examples

    use std::io;
    use std::io::prelude::*;
    use std::fs::File;

    let mut file = File::open("foo.txt")?;

    let mut buffer = [0; 5];
    let mut handle = file.take(5);
    handle.read(&mut buffer)?;

    let file = handle.into_inner();Run

#### `fn get_ref(&self) -> &T`
1.20.0
[src]

Gets a reference to the underlying reader.

# Examples

    use std::io;
    use std::io::prelude::*;
    use std::fs::File;

    let mut file = File::open("foo.txt")?;

    let mut buffer = [0; 5];
    let mut handle = file.take(5);
    handle.read(&mut buffer)?;

    let file = handle.get_ref();Run

#### `fn get_mut(&mut self) -> &mut T`
1.20.0
[src]

Gets a mutable reference to the underlying reader.

Care should be taken to avoid modifying the internal I/O state of the underlying reader as doing so may corrupt the internal limit of this `Take`.

# Examples

    use std::io;
    use std::io::prelude::*;
    use std::fs::File;

    let mut file = File::open("foo.txt")?;

    let mut buffer = [0; 5];
    let mut handle = file.take(5);
    handle.read(&mut buffer)?;

    let file = handle.get_mut();Run

## Trait Implementations

### `impl<T: Debug> Debug for Take<T>`
[src]

#### `fn fmt(&self, __arg_0: &mut Formatter) -> Result`
[src]

Formats the value using the given formatter.

### `impl<T: Read> Read for Take<T>`
[src]

#### `fn read(&mut self, buf: &mut [u8]) -> Result<usize>`
[src]

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

#### `unsafe fn initializer(&self) -> Initializer`
[src]

🔬 This is a nightly-only experimental API. (`read_initializer` #42788)

Determines if this `Read`er can work with buffers of uninitialized memory. Read more

#### `fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize>`
[src]

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

#### `fn read_to_string(&mut self, buf: &mut String) -> Result<usize>`
[src]

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

#### `fn read_exact(&mut self, buf: &mut [u8]) -> Result<()>`
1.6.0
[src]

Read the exact number of bytes required to fill `buf`. Read more

#### `fn by_ref(&mut self) -> &mut Self where
Self: Sized,`
[src]

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

#### `fn bytes(self) -> Bytes<Self> where
Self: Sized,`
[src]

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

#### `fn chars(self) -> Chars<Self> where
Self: Sized,`
[src]

🔬 This is a nightly-only experimental API. (`io` #27802)

the semantics of a partial read/write of where errors happen is currently unclear and may change

Transforms this `Read` instance to an [`Iterator`] over [`char`]s. Read more

#### `fn chain<R: Read>(self, next: R) -> Chain<Self, R> where
Self: Sized,`
[src]

Creates an adaptor which will chain this stream with another. Read more

#### `fn take(self, limit: u64) -> Take<Self> where
Self: Sized,`
[src]

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

### `impl<T: BufRead> BufRead for Take<T>`
[src]

#### `fn fill_buf(&mut self) -> Result<&[u8]>`
[src]

Fills the internal buffer of this object, returning the buffer contents. Read more

#### `fn consume(&mut self, amt: usize)`
[src]

Tells this buffer that `amt` bytes have been consumed from the buffer, so they should no longer be returned in calls to `read`. Read more

#### `fn read_until(&mut self, byte: u8, buf: &mut Vec<u8>) -> Result<usize>`
[src]

Read all bytes into `buf` until the delimiter `byte` or EOF is reached. Read more

#### `fn read_line(&mut self, buf: &mut String) -> Result<usize>`
[src]

Read all bytes until a newline (the 0xA byte) is reached, and append them to the provided buffer. Read more

#### `fn split(self, byte: u8) -> Split<Self> where
Self: Sized,`
[src]

Returns an iterator over the contents of this reader split on the byte `byte`. Read more

#### `fn lines(self) -> Lines<Self> where
Self: Sized,`
[src]

Returns an iterator over the lines of this reader. Read more

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