> For the complete documentation index, see [llms.txt](https://founders-and-coders.gitbook.io/coursebook/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://founders-and-coders.gitbook.io/coursebook/src/workshops/node-scripting-challenge/index.md). # index Write custom Node scripts to automate tasks in your terminal Node isn't just used for HTTP servers—it's a fully-fledged programming language that can do almost anything. Let's see how we can use it to create useful scripts we can run in our terminal. We could recreate the built-in `ls` program using Node's filesystem module: ```javascript // ls.js const fs = require("fs/promises"); const currentDir = process.cwd(); fs.readdir(currentDir).then((files) => { files.forEach((file) => console.log(file)); }); ``` We're importing `"fs/promises"` because Node's standard `"fs"` module uses callbacks. We get the directory the script was run from using `process.cwd()` ("current working directory"). Finally we use `fs.readdir` to get the names of every file in the directory and log them. You can run this script using `node ./path/to/ls.js`. It should list the contents of whatever directory you're currently inside in your terminal. We're currently running it by passing the file to our `node` program. However we can make the script directly executable by doing two things: First we must add a \["shebang"]\() to the top of the file. This is a special comment that tells the terminal which program it should use to run a script. ```javascript #! /usr/bin/env node // ... ``` Second you need to change the file's permissions to make it "executable". You can do so with: ``` chmod +x ls.js ``` You can now run this script with `./path/to/ls.js`. You actually don't even need the `.js` extension anymore, since the shebang tells your terminal that it's a Node file. So you could rename it to just `ls` and run it with `./path/to/ls`. ## Challenge Write a Node script that creates a new HTML file containing all the boilerplate code you normally need. The filename should be passed in as an argument. E.g. running this command: ``` ./create-html hello-world ``` should create a new file named `hello-world.html` containing: ```markup hello world

hello world

```