title: Shell script does not get parameters
body: <p>I have this script</p>
  <pre class="lang-sh prettyprint-override"><code>#!/bin/sh
  
  usage () {
  
  echo &quot;Usage: $0 {saludar}&quot;
  exit 1
  }
  
  saludo() {
  
  a=$1
  
  echo &quot;hola&quot; $a
  
  }
  
  case $1 in
  &quot;saludar&quot;) saludo;;
  *) usage;;
  esac
  </code></pre>
  <p>I don´t know why $a is always empty.</p>