Rust, libzmq, 客户端只发送消息，然后是接收

我正在测试 Rust libzmq 客户端

https://crates.io/crates/libzmq

https://docs.rs/libzmq/0.2.5/libzmq/struct.ClientBuilder.html

并偶然发现了这种奇怪的行为。

此客户端不会发送消息：

use libzmq::{prelude::*, *, ServerBuilder, ClientBuilder, TcpAddr};

fn main() -> Result<(), String> {
    
    let saddr = format!("{}:{}", "192.168.1.206","5540");
    println!("Strating client for {}", saddr);
    let addr2: TcpAddr = saddr.try_into().unwrap();
    
    let client = ClientBuilder::new()
        .connect(&addr2)
        .build().unwrap();
    client.send("test").unwrap();

    println!("Finished");
    Ok(())
}

这将发送：

use libzmq::{prelude::*, *, ServerBuilder, ClientBuilder, TcpAddr};

fn main() -> Result<(), String> {
    
    let saddr = format!("{}:{}", "192.168.1.206","5540");
    println!("Strating client for {}", saddr);
    let addr2: TcpAddr = saddr.try_into().unwrap();
    
    let client = ClientBuilder::new()
        .connect(&addr2)
        .build().unwrap();
    client.send("test").unwrap();

    let mut msg = Msg::new();
    client.recv(&mut msg).unwrap();

    println!("Finished");
    Ok(())
}

为了接收，我使用的是 python 服务器（但我也在 Rust 上进行了测试）：

import zmq
if __name__ == '__main__':

    context = zmq.Context()
    socket = context.socket(zmq.SERVER)
    socket.bind("tcp://0.0.0.0:5540")
    print("waiting for hand shake")
    m = socket.recv(copy=False)
    print("got it...")
    socket.send(b'READY', routing_id=m.routing_id)
    print("sent reply")
    socket.close()
    context.term()

代码 1 在服务器端的输出：

waiting for hand shake
[blocked]

代码 2 在服务器端的输出：

waiting for hand shake
got it...
sent reply

将此版本用于 Rust：

[dependencies]
libzmq = "0.2.5"