Change io crate & add a small shell

user/agetty/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "agetty"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]

user/agetty/src/main.rs

@@ -0,0 +1,29 @@
+#![allow(unused)]
+#![feature(survos_std)]
+
+use core::sync::atomic::AtomicUsize;
+use std::fs::File;
+use std::io::{Read, Stdin, Write, stdin, stdout};
+use std::os::fd::FromRawFd;
+
+fn main() {
+    // Close descriptor 0
+    let f = unsafe { File::from_raw_fd(0) };
+    drop(f);
+
+    // Close descriptor 1
+    let f = unsafe { File::from_raw_fd(1) };
+    drop(f);
+
+    // Open new input and output
+    let mut input = File::open("/dev/tty0");
+    let mut tty = File::open("/dev/tty0");
+
+    std::process::Command::new("/usr/bin/shell")
+        .spawn()
+        .unwrap();
+
+    loop {
+        std::thread::yield_now();
+    }
+}