Trait futures_lite::io::AsyncBufReadExt
source · pub trait AsyncBufReadExt: AsyncBufRead {
// Provided methods
fn fill_buf(&mut self) -> FillBuf<'_, Self> ⓘ
where Self: Unpin { ... }
fn consume(&mut self, amt: usize)
where Self: Unpin { ... }
fn read_until<'a>(
&'a mut self,
byte: u8,
buf: &'a mut Vec<u8>
) -> ReadUntilFuture<'_, Self> ⓘ
where Self: Unpin { ... }
fn read_line<'a>(
&'a mut self,
buf: &'a mut String
) -> ReadLineFuture<'_, Self> ⓘ
where Self: Unpin { ... }
fn lines(self) -> Lines<Self>
where Self: Unpin + Sized { ... }
fn split(self, byte: u8) -> Split<Self>
where Self: Sized { ... }
}
Expand description
Extension trait for AsyncBufRead
.
Provided Methods§
sourcefn fill_buf(&mut self) -> FillBuf<'_, Self> ⓘwhere
Self: Unpin,
fn fill_buf(&mut self) -> FillBuf<'_, Self> ⓘwhere
Self: Unpin,
Returns the contents of the internal buffer, filling it with more data if empty.
If the stream has reached EOF, an empty buffer will be returned.
§Examples
use futures_lite::io::{AsyncBufReadExt, BufReader};
use std::pin::Pin;
let input: &[u8] = b"hello world";
let mut reader = BufReader::with_capacity(5, input);
assert_eq!(reader.fill_buf().await?, b"hello");
reader.consume(2);
assert_eq!(reader.fill_buf().await?, b"llo");
reader.consume(3);
assert_eq!(reader.fill_buf().await?, b" worl");
sourcefn consume(&mut self, amt: usize)where
Self: Unpin,
fn consume(&mut self, amt: usize)where
Self: Unpin,
Consumes amt
buffered bytes.
This method does not perform any I/O, it simply consumes some amount of bytes from the internal buffer.
The amt
must be <= the number of bytes in the buffer returned by
fill_buf()
.
§Examples
use futures_lite::io::{AsyncBufReadExt, BufReader};
use std::pin::Pin;
let input: &[u8] = b"hello";
let mut reader = BufReader::with_capacity(4, input);
assert_eq!(reader.fill_buf().await?, b"hell");
reader.consume(2);
assert_eq!(reader.fill_buf().await?, b"ll");
sourcefn read_until<'a>(
&'a mut self,
byte: u8,
buf: &'a mut Vec<u8>
) -> ReadUntilFuture<'_, Self> ⓘwhere
Self: Unpin,
fn read_until<'a>(
&'a mut self,
byte: u8,
buf: &'a mut Vec<u8>
) -> ReadUntilFuture<'_, Self> ⓘwhere
Self: Unpin,
Reads all bytes and appends them into buf
until the delimiter byte
or EOF is found.
This method will read bytes from the underlying stream until the delimiter or EOF is
found. All bytes up to and including the delimiter (if found) will be appended to buf
.
If successful, returns the total number of bytes read.
§Examples
use futures_lite::io::{AsyncBufReadExt, BufReader};
let input: &[u8] = b"hello";
let mut reader = BufReader::new(input);
let mut buf = Vec::new();
let n = reader.read_until(b'\n', &mut buf).await?;
sourcefn read_line<'a>(&'a mut self, buf: &'a mut String) -> ReadLineFuture<'_, Self> ⓘwhere
Self: Unpin,
fn read_line<'a>(&'a mut self, buf: &'a mut String) -> ReadLineFuture<'_, Self> ⓘwhere
Self: Unpin,
Reads all bytes and appends them into buf
until a newline (the 0xA byte) or EOF is found.
This method will read bytes from the underlying stream until the newline delimiter (the
0xA byte) or EOF is found. All bytes up to, and including, the newline delimiter (if found)
will be appended to buf
.
If successful, returns the total number of bytes read.
§Examples
use futures_lite::io::{AsyncBufReadExt, BufReader};
let input: &[u8] = b"hello";
let mut reader = BufReader::new(input);
let mut line = String::new();
let n = reader.read_line(&mut line).await?;
sourcefn lines(self) -> Lines<Self>
fn lines(self) -> Lines<Self>
Returns a stream over the lines of this byte stream.
The stream returned from this method yields items of type
io::Result
<
String
>
.
Each string returned will not have a newline byte (the 0xA byte) or CRLF (0xD, 0xA bytes)
at the end.
§Examples
use futures_lite::io::{AsyncBufReadExt, BufReader};
use futures_lite::stream::StreamExt;
let input: &[u8] = b"hello\nworld\n";
let mut reader = BufReader::new(input);
let mut lines = reader.lines();
while let Some(line) = lines.next().await {
println!("{}", line?);
}
sourcefn split(self, byte: u8) -> Split<Self>where
Self: Sized,
fn split(self, byte: u8) -> Split<Self>where
Self: Sized,
Returns a stream over the contents of this reader split on the specified byte
.
The stream returned from this method yields items of type
io::Result
<
Vec<u8>
>
.
Each vector returned will not have the delimiter byte at the end.
§Examples
use futures_lite::io::{AsyncBufReadExt, Cursor};
use futures_lite::stream::StreamExt;
let cursor = Cursor::new(b"lorem-ipsum-dolor");
let items: Vec<Vec<u8>> = cursor.split(b'-').try_collect().await?;
assert_eq!(items[0], b"lorem");
assert_eq!(items[1], b"ipsum");
assert_eq!(items[2], b"dolor");