blob: e2cdde794d60a0da20bffb43aca0664b018b32e3 [file] [log] [blame] [edit]
//! Prints a file given as an argument to stdout.
use std::env::args;
use async_std::fs::File;
use async_std::io;
use async_std::prelude::*;
use async_std::task;
const LEN: usize = 16 * 1024; // 16 Kb
fn main() -> io::Result<()> {
let path = args().nth(1).expect("missing path argument");
task::block_on(async {
let mut file = File::open(&path).await?;
let mut stdout = io::stdout();
let mut buf = vec![0u8; LEN];
loop {
// Read a buffer from the file.
let n = file.read(&mut buf).await?;
// If this is the end of file, clean up and return.
if n == 0 {
stdout.flush().await?;
return Ok(());
}
// Write the buffer into stdout.
stdout.write_all(&buf[..n]).await?;
}
})
}