title: In bash, how to convert this hexa character to readable?
body: <p>Duplicate of <a href="https://unix.stackexchange.com/questions/159253/decoding-url-encoding-percent-encoding">https://unix.stackexchange.com/questions/159253/decoding-url-encoding-percent-encoding</a>, but SO does not understand url from different stack.</p>
  <p>Inside a docker container, I use environment variables (that I do not manage initialy, so I cannot act on them) inside a bash script.</p>
  <p>One of the environement variable has one hexa character, but the rest of the string is OK.</p>
  <p>Original string is: <code>toto@t</code>.</p>
  <p>It is recuperated as <code>toto%40t</code> in the script with the following command:</p>
  <pre><code>echo &quot;$VAR&quot;
  </code></pre>
  <p>Note the <code>@</code> that is transformed into <code>%40</code></p>
  <p>With &quot;minimal Ubuntu 20&quot; (Installation of additionnal tools is possible, but I want to avoid it), pure bash if possible, how can I format the variable to get the original format ?</p>