// { "preopens": { "/scratch": "scratch" } } use std::io::Write; fn main() { let mut file = std::fs::File::create("/scratch/file").unwrap(); assert!(file.write(b"Hello").is_ok()); assert!(file.sync_data().is_ok()); assert_eq!(std::fs::read("/scratch/file").unwrap(), b"Hello"); assert!(file.write(b", world!").is_ok()); assert!(file.sync_data().is_ok()); assert_eq!(std::fs::read("/scratch/file").unwrap(), b"Hello, world!"); }