# A notification when a long task ends

> Send an OSC 9 desktop notification on terminals that show one, and print the same message as a line everywhere else — with no native binaries.

Source: https://paratext.interlace.tools/docs/recipes/notify-when-done

A build that takes ten minutes should say when it is done. On iTerm2, WezTerm and Ghostty,
OSC 9 raises a desktop notification with no native helper installed; everywhere else the same
call prints the message as a line, which is what a CI log wants anyway.

```js title="done.mjs"
import { emit, processRuntime } from 'paratext';

const started = Date.now();
// … the long task …
const seconds = Math.round((Date.now() - started) / 1000);

process.stdout.write(`${emit(processRuntime(), 'notify', { title: 'Build finished', body: `${seconds}s` })}\n`);
```

```text title="node done.mjs"
Build finished: 0s
```

On a supporting terminal the line is the notification's bytes instead, and the terminal shows
the notification rather than the text. `body` is optional: `{title}[: {body}]` prints the title
alone when there is no body.