title: How to use NSIS Unicode \\?\ prefix for long pathnames
body: <p>I'm using NSIS for installer creation, but have a problem with long pathnames (>260 characters). I've heard of an unicode version, which can handle long pathnames with a special prefix <code>\\?\</code>.
  I wonder if there's any docs describing what the <code>\\?\</code> prefix does and how it is used. I am  using <code>File /r /x root ..*</code> in the non-unicode NSIS version.</p>
  
  <p>The same problem is described here <a href="https://stackoverflow.com/questions/15536817/increase-allowable-file-path-length">Increase Allowable File Path Length</a> but no real solution.</p>
  
  <p>OS is Windows 7, the error message is </p>
  
  <pre><code>File: failed opening file "..\server\WEB-INF\classes\some\very\long\and\winding\path\myFile.txt"
  Error in script "D:\real\long\path\to\nsis\my.nsis.updater.nsi" on line 116 -- aborting creation process
  </code></pre>
  
  <p>This line is the call of</p>
  
  <pre><code>File /r /x nsis ..\*
  </code></pre>
  
  <p>which packs my content.</p>