Function smol::reader

pub fn reader(
    reader: impl Read + Send + 'static
) -> impl AsyncRead + Send + Unpin + 'static

Creates an async reader that runs on a thread.

This adapter converts any kind of synchronous reader into an asynchronous reader by running it on the blocking executor and sending bytes back over a pipe.

Examples

Read from a file:

use futures::prelude::*;
use smol::{blocking, reader};
use std::fs::File;

// Open a file for reading.
let file = blocking!(File::open("foo.txt"))?;
let mut file = reader(file);

// Read the whole file.
let mut contents = Vec::new();
file.read_to_end(&mut contents).await?;

Read output from a process:

use futures::prelude::*;
use smol::reader;
use std::process::{Command, Stdio};

// Spawn a child process and make an async reader for its stdout.
let child = Command::new("dir").stdout(Stdio::piped()).spawn()?;
let mut child_stdout = reader(child.stdout.unwrap());

// Read the entire output.
let mut output = String::new();
child_stdout.read_to_string(&mut output).await?;