use std::os::unix::io::{AsRawFd, FromRawFd, RawFd};
use tokio::fs::File;
use tokio::io::{AsyncBufReadExt, BufReader};

#[tokio::main]
async fn main() {
    let file = File::open("Cargo.toml").await.unwrap();
    let fd = file.as_raw_fd();
    wait_and_read(fd).await;
}

async fn wait_and_read(fd: RawFd) {
    let f: File = unsafe { File::from_raw_fd(fd) };
    let f = BufReader::new(f);
    let mut lines = f.lines();
    while let Some(s) = lines.next_line().await.unwrap() {
        println!("{}", s);
    }
}

这里的RawFd是c_int的别名，假如你是u32的fd直接as一下就行了。

--
👇
kcrazy: 谢谢，请问有具体的例子吗？

比如说有这么个函数，应该怎么写呢？

async fn wait_and_read(fd: u32) {
    ....
}

--
👇
Bai-Jinlin: ``` tokio::fs::File::from_raw_fd

谢谢，请问有具体的例子吗？

比如说有这么个函数，应该怎么写呢？

async fn wait_and_read(fd: u32) {
    ....
}

--
👇
Bai-Jinlin: ``` tokio::fs::File::from_raw_fd

tokio::fs::File::from_raw_fd