cat_clone/
lib.rs

1use clap::Parser;
2use std::{path, process, fs::File, error::Error, io::{self, BufReader, prelude::*, BufWriter, Stdout}};
3use anyhow::{Context, Result};
4
5/// Display the content of a file
6#[derive(Parser)]
7pub struct Cli {
8    /// Path to the file 
9    path: path::PathBuf
10}
11
12pub fn run(args: &Cli) -> Result<(), Box<dyn Error>> {
13    let handle = buffered_stdout();
14
15    let _ = read_file(&args, handle)?;
16
17
18    Ok(())
19}
20
21fn read_file(args: &Cli, mut writer: impl std::io::Write) -> Result<(), Box<dyn Error>> {
22
23    let file = File::open(&args.path)?;
24    let mut reader = BufReader::new(file);
25
26    let mut content = String::new();
27
28    while reader.read_line(&mut content)
29                .with_context(|| format!("could not read file: `{}`", &args.path.to_string_lossy()))
30                .unwrap() > 0 
31    {
32        writeln!(writer, "{}", content.trim()).unwrap_or_else(|err| {
33            eprintln!("Couldn't write to the terminal, {}", err);
34            process::exit(1);
35        });
36        content.clear();
37        
38    }
39
40    Ok(())
41}
42
43fn buffered_stdout() -> BufWriter<Stdout> {
44    let stdout = io::stdout();
45    let handle = io::BufWriter::new(stdout);
46
47    handle
48}
cat_clone/lib.rs

cat_clone/
lib.rs
