[−][src]Trait futures::io::AsyncBufReadExt

pub trait AsyncBufReadExt: AsyncBufRead {
    fn read_until(
        &'a mut self, 
        byte: u8, 
        buf: &'a mut Vec<u8>
    ) -> ReadUntil<'a, Self>
    where
        Self: Unpin,
    { ... }
}
[−]

An extension trait which adds utility methods to AsyncBufRead types.

Provided methods

Creates a future which will read all the bytes associated with this I/O object into buf until the delimiter byte or EOF is reached. This method is the async equivalent to BufRead::read_until.

This function will read bytes from the underlying stream until the delimiter or EOF is found. Once found, all bytes up to, and including, the delimiter (if found) will be appended to buf.

The returned future will resolve to the number of bytes read once the read operation is completed.

In the case of an error the buffer and the object will be discarded, with the error yielded.

Examples

#![feature(async_await, await_macro)]
use futures::io::AsyncBufReadExt;
use std::io::Cursor;

let mut cursor = Cursor::new(b"lorem-ipsum");
let mut buf = vec![];

// cursor is at 'l'
let num_bytes = await!(cursor.read_until(b'-', &mut buf))?;
assert_eq!(num_bytes, 6);
assert_eq!(buf, b"lorem-");
buf.clear();

// cursor is at 'i'
let num_bytes = await!(cursor.read_until(b'-', &mut buf))?;
assert_eq!(num_bytes, 5);
assert_eq!(buf, b"ipsum");
buf.clear();

// cursor is at EOF
let num_bytes = await!(cursor.read_until(b'-', &mut buf))?;
assert_eq!(num_bytes, 0);
assert_eq!(buf, b"");

Implementors

impl<R> AsyncBufReadExt for R where
    R: AsyncBufRead + ?Sized, [src][−]

ⓘImportant traits for ReadUntil<'_, R>
fn read_until(
    &'a mut self,
    byte: u8,
    buf: &'a mut Vec<u8>
) -> ReadUntil<'a, Self> where
    Self: Unpin, [src]