Spawn a command in Rust with separate STDIO and then print it out to the main thread's STDOUT (or whatever buffer you want).

rust_spawn_command.rs

let process = Command::new("randomstrings").stdin(Stdio::piped()).stdout(Stdio::piped()).spawn().unwrap();
let mut thing = process.stdout.unwrap();

loop {
    let something: &mut [u8] = &mut [0];
    thing.read(something);
    print!("{}", std::str::from_utf8(something).unwrap())
}