# 1.0.0[−][src]Struct std::io::Take

    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]

#### `pub 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;

    fn main() -> io::Result<()> {
        let f = File::open("foo.txt")?;

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

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

Run

#### `pub fn set_limit(&mut self, limit: u64)`1.27.0[src]

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

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

    fn main() -> io::Result<()> {
        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);
        Ok(())
    }

Run

#### `pub 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;

    fn main() -> io::Result<()> {
        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();
        Ok(())
    }

Run

#### `pub 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;

    fn main() -> io::Result<()> {
        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();
        Ok(())
    }

Run

#### `pub 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;

    fn main() -> io::Result<()> {
        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();
        Ok(())
    }

Run

## Trait Implementations

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

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

Returns the contents of the internal buffer, filling it with more data from the inner reader if it is empty. 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

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

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

Formats the value using the given formatter. Read more

### `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_vectored(&mut self, bufs: &mut [IoSliceMut]) -> Result<usize>`1.36.0[src]

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

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

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

## Auto Trait Implementations

### `impl<T> RefUnwindSafe for Take<T> where
T: RefUnwindSafe,`

### `impl<T> Send for Take<T> where
T: Send,`

### `impl<T> Sync for Take<T> where
T: Sync,`

### `impl<T> Unpin for Take<T> where
T: Unpin,`

### `impl<T> UnwindSafe for Take<T> where
T: UnwindSafe,`

## Blanket Implementations

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

#### `fn type_id(&self) -> TypeId`[src]

Gets the `TypeId` of `self`. Read more

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

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

Immutably borrows from an owned value. Read more

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

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

Mutably borrows from an owned value. Read more

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

#### `fn from(t: T) -> T`[src]

Performs the conversion.

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

#### `fn into(self) -> U`[src]

Performs the conversion.

### `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.

#### `fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>`[src]

Performs the conversion.

### `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.

#### `fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>`[src]

Performs the conversion.