title: Can't use var1=$(cmd) in bash script (only in unix)
body: <p>I'm trying to do this:</p>
  
  <pre><code>OS=$(uname -s)
  </code></pre>
  
  <p>It runs fine at the terminal, but, it throws this: </p>
  
  <blockquote>
    <p>syntax error on line x:'OS=$' unexpected</p>
  </blockquote>
  
  <p>I'm using #!/bin/bash.</p>