Linux - Check if a file has multiple lines : <p>Is there a command or bash function to check if a file has multiple lines?
Lets say i have these two files:</p>

<p><strong>foo.txt</strong></p>

<pre><code>Hello World
</code></pre>

<p><strong>bar.txt</strong></p>

<pre><code>Hello
World
</code></pre>
