title: Is Python's os.fstat available on every platform?
body: <p>The documentation on <code>os.stat()</code> and <code>os.fstat()</code> is somewhat confusing about this. On <code>os.stat()</code> it says that on some platforms, it also accepts file descriptors and that the <code>os.supports_fd</code> set can be used to check if that's the case. On <code>os.fstat()</code> it says nothing about platforms, but that, as of Python 3.3, it is equivalent to <code>os.stat()</code>.</p>
  
  <p>Does equivalent mean "alias" here, and that on systems where <code>os.stat()</code> does not support file descriptors, I can not use them at all, or does it mean, that on such systems I just have to use <code>os.fstat()</code> instead?</p>
  
  <p>Furthermore are there any widely used platforms, that do not support using file descriptors for <code>stat</code> anyway, or is this just some kind of "there might be platforms not supporting it, but we don't know of any"?</p>