init: Improve command spawning

The stdout and stderr of the spawned processes are not captured by init,
so attempting to write captured input is useless. Also show the exit
code in case the child process returned an non-zero exit code.

init/src/main.rs

@@ -2,7 +2,7 @@ use std::collections::BTreeMap;
 use std::env;
 use std::ffi::CString;
 use std::fs::{read_dir, File};
-use std::io::{BufRead, BufReader, Result, Write};
+use std::io::{BufRead, BufReader, Result};
 use std::path::Path;
 use std::process::Command;
 
@@ -186,15 +186,13 @@ pub fn run(file: &Path) -> Result<()> {
                         }
 
                         match command.spawn() {
-                            Ok(child) => match child.wait_with_output() {
-                                Ok(output) => {
-                                    std::io::stdout()
-                                        .write_all(output.stdout.as_slice())
-                                        .unwrap();
-                                    std::io::stderr()
-                                        .write_all(output.stderr.as_slice())
-                                        .unwrap();
-                                    println!("{cmd} done.");
+                            Ok(mut child) => match child.wait() {
+                                Ok(exit_status) => {
+                                    if !exit_status.success() {
+                                        println!("{cmd} failed with {exit_status}");
+                                    } else {
+                                        println!("{cmd} done.");
+                                    }
                                 }
                                 Err(err) => {
                                     println!("init: failed to wait for '{}': {}", line, err)