use completeio::fs::OpenOptions;
fn main() {
let buffer = completeio::task::block_on(async {
let file = OpenOptions::new().read(true).open("Cargo.toml").unwrap();
let (read, buffer) = file.read_to_end_at(Vec::with_capacity(4096), 0).await;
let read = read.unwrap();
assert_eq!(read, buffer.len());
String::from_utf8(buffer).unwrap()
});
println!("{}", buffer);
}