use read_write_pipe::*;
use std::fs::{File, OpenOptions};
use std::io;
use std::io::Write;
fn prepare_input() -> io::Result<()> {
let mut f = OpenOptions::new()
.read(true)
.write(true)
.create(true)
.open("a.txt")?;
f.write_all(b"some content")
}
fn main() -> io::Result<()> {
prepare_input()?;
let input = File::open("a.txt")?;
let mut output = OpenOptions::new()
.read(true)
.write(true)
.create(true)
.open("b.txt")?;
let _ = output.write_reader(input)?;
Ok(())
}