title: How to access InstallDirRegKey in NSIS
body: <p>I can specify installation directory and registry value in NSIS like this:</p>
  
  <pre><code>InstallDir "$PROGRAMFILES\CTVI"
  InstallDirRegKey HKLM "Software\CTVI" "Install_Dir"
  </code></pre>
  
  <p>Now I can access <code>InstallDir</code> by using the notation <code>$INSTDIR</code> throughout the script. <strong>How do I similarly access <code>InstallDirRegKey</code>?</strong> Is there a similar notation as there exists for <code>InstallDir</code>? I tried <code>$INSTDIRREGKEY</code> but that is not. Now what I do is that I type <code>HKLM "Software\CTVI" "Install_Dir"</code> everytime I require it. But that is not so DRY :)</p>