title: Can't read file using nodejs fs module when file name is stored in environment variable
body: <p>I am running a node app in ubuntu server 16.04. I have set up an environment variable: </p>
  
  <pre><code>export FILE_PATH="file-path"
  </code></pre>
  
  <p>Then I tried to read the file in my node script:</p>
  
  <pre><code>const fs   = require('fs');
  console.log(process.env.FILE_PATH); // gives correct path.
  const data = fs.readFileSync((process.env.FILE_PATH || ""), 'utf8');
  </code></pre>
  
  <p>But I'm getting "no such file or directory" error in debugger. The file is existing and has required permissions. If I give the path directly instead of taking from env variable, it will work.</p>