title: Get first character of a string SHELL
body: <p>I want to first the first character of a string, for example:</p>
  
  <p><code>$&gt;./first $foreignKey</code></p>
  
  <p>And I want to get <code>"$"</code></p>
  
  <p>I googled it and I found some solutions but it concerns only bash and not <code>Sh !</code></p>