title: cmake script mode what is supported and what not
body: <p>I'm using cmake to build one of my projects, I see the way it installs files is calling a cmake script by <code>cmake -P cmake_install.cmake</code>, but the functions used in this cmake file looks different than what is documented, e.g. for shared library install target it has:</p>
  <pre><code>file(RPATH_CHECK FILE ... RPATH ...)
  </code></pre>
  <p>But I cannot find this file sub-command in the <a href="https://cmake.org/cmake/help/latest/command/file.html" rel="nofollow noreferrer">cmake documentation</a>, so is there a place that have the available functions to use in script mode?</p>