title: What is the "done" function/meaning in the bash while loop?
body: <p>I am a new guy for bash shell. I am confused by the below script. </p>
  
  <pre><code>#!/bin/bash
  
  input=name.csv
  
  while IFS=',' read -r Family_name First_name
  
  do
  
   echo $Family_name
   echo $First_name
  
  done &lt; $input
  </code></pre>
  
  <p>Intuitively, I thought the <code>done</code> is some kind of boundary marker that told you the <code>while</code> field is over.</p>
  
  <p>Here it shows that <code>done</code> can take data from a variable. so what is the meaning/function of <code>done</code> in the <code>while</code> loop?  Thanks.</p>