Struct tokio::net::tcp::ReadHalf[][src]

pub struct ReadHalf<'a>(_);
Expand description

Borrowed read half of a TcpStream, created by split.

Reading from a ReadHalf is usually done using the convenience methods found on the AsyncReadExt trait.

Implementations

Attempt to receive data on the socket, without removing that data from the queue, registering the current task for wakeup if data is not yet available.

Note that on multiple calls to poll_peek or poll_read, only the Waker from the Context passed to the most recent call is scheduled to receive a wakeup.

See the TcpStream::poll_peek level documentation for more details.

Examples
use tokio::io::{self, ReadBuf};
use tokio::net::TcpStream;

use futures::future::poll_fn;

#[tokio::main]
async fn main() -> io::Result<()> {
    let mut stream = TcpStream::connect("127.0.0.1:8000").await?;
    let (mut read_half, _) = stream.split();
    let mut buf = [0; 10];
    let mut buf = ReadBuf::new(&mut buf);

    poll_fn(|cx| {
        read_half.poll_peek(cx, &mut buf)
    }).await?;

    Ok(())
}

Receives data on the socket from the remote address to which it is connected, without removing that data from the queue. On success, returns the number of bytes peeked.

See the TcpStream::peek level documentation for more details.

Examples
use tokio::net::TcpStream;
use tokio::io::AsyncReadExt;
use std::error::Error;

#[tokio::main]
async fn main() -> Result<(), Box<dyn Error>> {
    // Connect to a peer
    let mut stream = TcpStream::connect("127.0.0.1:8080").await?;
    let (mut read_half, _) = stream.split();

    let mut b1 = [0; 10];
    let mut b2 = [0; 10];

    // Peek at the data
    let n = read_half.peek(&mut b1).await?;

    // Read the data
    assert_eq!(n, read_half.read(&mut b2[..n]).await?);
    assert_eq!(&b1[..n], &b2[..n]);

    Ok(())
}

The read method is defined on the AsyncReadExt trait.

Trait Implementations

Performs the conversion.

Attempts to read from the AsyncRead into buf. Read more

Formats the value using the given formatter. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Performs the conversion.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.