Function tokio::sync::mpsc::channel

source ·
pub fn channel<T>(buffer: usize) -> (Sender<T>, Receiver<T>)
Expand description

Creates a bounded mpsc channel for communicating between asynchronous tasks with backpressure.

The channel will buffer up to the provided number of messages. Once the buffer is full, attempts to send new messages will wait until a message is received from the channel. The provided buffer capacity must be at least 1.

All data sent on Sender will become available on Receiver in the same order as it was sent.

The Sender can be cloned to send to the same channel from multiple code locations. Only one Receiver is supported.

If the Receiver is disconnected while trying to send, the send method will return a SendError. Similarly, if Sender is disconnected while trying to recv, the recv method will return None.


Panics if the buffer capacity is 0.


use tokio::sync::mpsc;

async fn main() {
    let (tx, mut rx) = mpsc::channel(100);

    tokio::spawn(async move {
        for i in 0..10 {
            if let Err(_) = tx.send(i).await {
                println!("receiver dropped");

    while let Some(i) = rx.recv().await {
        println!("got = {}", i);