[Rust lang] Read files and send it via serialport

main.rs

use std::fs::File;
use std::io::prelude::*;

use serialport::available_ports;

fn main() {
    let mut file = File::open("info.txt").expect("Can't open the file");

    let mut contents = String::new();

    file.read_to_string(&mut contents)
        .expect("Can't read file");

    println!("File content: {}", contents);

    let ports = available_ports().expect("No ports found");
    for p in ports {
        println!("{}", p.port_name);
    }

}

> cargo run
Compiling test_files v0.1.0 (test_files)
warning: unused import: `serialport::available_ports`
--> src\main.rs:4:5
| 4 | use serialport::available_ports;
|     ^^^^^^^^^^^^^^^^^^^^^^^^^^^ 
|= note: `#[warn(unused_imports)]` on by default                                                                                                                                                           warning: 1 warning emitted                                                                                                                                                                                      Finished dev [unoptimized + debuginfo] target(s) in 0.87s
Running `target\debug\test_files.exe`
File content: Hola                                                                                                                                                                                          

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