[learn_dart] process

notes/learn_dart/test/dart_lang!sdk!io/process.dart

@@ -0,0 +1,32 @@
+// ignore_for_file: avoid_print
+
+import 'dart:convert';
+import 'dart:io';
+import 'package:path/path.dart' as path;
+
+main() async {
+  var cmd = path.join(path.current, "test/dart_lang!sdk!io/process.sh");
+  await runProcess(cmd, []);
+}
+
+Future<void> runProcess(
+  String command,
+  List<String> args, {
+  String? cwd,
+}) async {
+  print('\n$command ${args.join(' ')}');
+
+  var process = await Process.start(command, args, workingDirectory: cwd);
+
+  process.stdout.transform(utf8.decoder).transform(LineSplitter()).listen((line) {
+    print('  $line');
+  });
+  process.stderr.transform(utf8.decoder).transform(LineSplitter()).listen((line) {
+    print('  $line');
+  });
+
+  var exitCode = await process.exitCode;
+  if (exitCode != 0) {
+    throw '$command exited with $exitCode';
+  }
+}

notes/learn_dart/test/dart_lang!sdk!io/process.sh

@@ -0,0 +1,3 @@
+#!/usr/bin/env bash
+
+for i in {1..3} ; do echo $i;sleep 1; done;