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use std::{
io::Write,
{env, io},
};
use tokio_uring::fs::File;
fn main() {
// The file to `cat` is passed as a CLI argument
let args: Vec<_> = env::args().collect();
if args.len() <= 1 {
panic!("no path specified");
}
let path = &args[1];
// Lock stdout
let out = io::stdout();
let mut out = out.lock();
tokio_uring::start(async {
// Open the file without blocking
let file = File::open(path).await.unwrap();
let mut buf = vec![0; 16 * 1_024];
// Track the current position in the file;
let mut pos = 0;
loop {
// Read a chunk
let (res, b) = file.read_at(buf, pos).await;
let n = res.unwrap();
if n == 0 {
break;
}
out.write_all(&b[..n]).unwrap();
pos += n as u64;
buf = b;
}
// Include a new line
println!();
});
}