title: What is the root path to a file on Windows? On MacOS?
body: <p>I apologize for the simplicity of this question.  I'm learning to program in python, and my most recent task is learning to work with files.  Unfortunately I seem to be unable to correctly frame a path statement to open a specific file.  To make things even more interesting, I'm bi-OS-usal.  I work on both MacOS and Windows.  </p>
  
  <p>I've tried using the "os" module in python to generate an OS specific path that should work on either OS, but I continue to get FileNotFoundError.  Here's what I tried on the Mac.  Note that the path to the file is on the main drive (Macintosh HD) in the Users folder under my directory, toddb.  Filename is st.txt</p>
  
  <pre><code>import os
  path = os.path.join("Users", "toddb", "st.txt")
  stlaunch = open(path, "r")
  </code></pre>
  
  <p>At this point I get:</p>
  
  <pre><code>FileNotFoundError: [Errno 2] No such file or directory:
  </code></pre>
  
  <p>Since I didn't explicitly state the root drive I also tried:</p>
  
  <pre><code>path = os.path.join("Macintosh HD", "Users", "toddb", "st.txt")
  </code></pre>
  
  <p>Same error when I run my code.</p>