rust_tail.rs

use std::io::{BufReader,BufRead};
use std::fs::File;
use std::time::Duration;
use std::thread;
use std::env;

fn main() {
    fn tail(reader: &mut BufReader<&File>) {
        let time = Duration::from_millis(10);
        loop {
            let mut line = String::new();
            reader.read_line(&mut line).unwrap();
            if line == "" {
                thread::sleep(time);
            } else {
                print!("{}", line);
            }
        }
    }

    let path = &env::args().nth(1).unwrap();
    match File::open(path) {
      Ok(file) => {
          let mut reader = BufReader::new(&file);
          tail(&mut reader);
      },
      Err(e) => {
          println!("{}", e);
      }
    }
}

A elixir version