Unable to use RequestReplier in async task #38
Description
This sample code gives an error:
#[tokio::main]
async fn main() {
let ctx = tmq::Context::new();
let handle = tokio::task::spawn(async move {
let mut socket = tmq::reply(&ctx).bind("tcp://0.0.0.0:5001").unwrap();
loop {
let (msg, req) = socket.recv().await.unwrap();
socket = req.send(msg).await.unwrap();
}
});
handle.await.unwrap();
}Output:
error: future cannot be sent between threads safely
--> src/main.rs:4:37
|
4 | let handle = tokio::task::spawn(async move {
| _____________________________________^
5 | | let mut socket = tmq::reply(&ctx).bind("tcp://0.0.0.0:5001").unwrap();
6 | | loop {
7 | | let (msg, req) = socket.recv().await.unwrap();
8 | | socket = req.send(msg).await.unwrap();
9 | | }
10 | | });
| |_____^ future created by async block is not `Send`
|
= help: within `RequestReceiver`, the trait `Sync` is not implemented for `*mut c_void`
note: future is not `Send` as this value is used across an await
--> /home/bemyak/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tmq-0.3.2/src/socket_types/request_reply.rs:54:79
|
54 | let msg = futures::future::poll_fn(|cx| self.inner.multipart_recv(cx)).await?;
| ---------------------------------- ^^^^^^ - `|cx| self.inner.multipart_recv(cx)` is later dropped here
| | |
| | await occurs here, with `|cx| self.inner.multipart_recv(cx)` maybe used later
| has type `[closure@RequestReceiver::recv::{closure#0}::{closure#0}]` which is not `Send`
note: required by a bound in `tokio::spawn`
--> /home/bemyak/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.26.0/src/task/spawn.rs:163:21
|
163 | T: Future + Send + 'static,
| ^^^^ required by this bound in `spawn`
Publish and Subscribe seem to work fine.
Any hints on how to fix this?