Walk directory in Rust

main.rs

extern crate walkdir;

use walkdir::WalkDir;
use std::fs::File;
use std::io::Read;

fn main() {
    let nul = 0;
    let mut bytes_count: i32;

    for entry in WalkDir::new("./").into_iter().filter_map(|e| e.ok()) {
        if entry.file_type().is_file() {
            let mut file = File::open(entry.path().display().to_string()).unwrap();

            bytes_count = 0;

            let mut s: Vec<u8> = Vec::with_capacity(file.metadata().unwrap().len() as usize);
            file.read_to_end(&mut s).unwrap();

            for b in s.into_iter() {
                if b == nul {
                    println!("{} bytes={} binary file", entry.path().display().to_string(), bytes_count);
                    break
                }

                bytes_count += 1;
            }

            println!("{} bytes={}", entry.path().display().to_string(), bytes_count)
        }
    }
}