---
title: Spawn a child process
sidebarTitle: Spawn child process
mode: center
---

Use [`Bun.spawn()`](/runtime/child-process) to spawn a child process.

```ts
const proc = Bun.spawn(["echo", "hello"]);

// await completion
await proc.exited;
```

---

The second argument is a configuration object.

```ts
const proc = Bun.spawn(["echo", "Hello, world!"], {
  cwd: "/tmp",
  env: { FOO: "bar" },
  onExit(proc, exitCode, signalCode, error) {
    // exit handler
  },
});
```

---

By default, `proc.stdout` is a `ReadableStream` of the child process's `stdout`.

```ts
const proc = Bun.spawn(["echo", "hello"]);

const output = await proc.stdout.text();
output; // => "hello\n"
```

---

See [Child processes](/runtime/child-process).
