title: How to fix 'Program install error' related to Xvfb and selenium on a Mac?
body: <p>I am trying to se a Mac (MacOS 10.13.3) to run selenium tests in an headless environment. I am doing basically the following:</p>
  
  <pre><code>from pyvirtualdisplay impot Display
  display = Display(visible=0, size=(13660, 7680))
  display.start()
  </code></pre>
  
  <p>before invoking the selenium webdriver (selenum 3.8.0). However, I get the following error: </p>
  
  <pre><code>self = &lt;EasyProcess cmd_param=['Xvfb', '-help'] cmd=['Xvfb', '-help'] oserror=[Errno ... directory return_code=None stdout="None" stderr="None" timeout_happened=False&gt;
  
      def check_installed(self):
          """Used for testing if program is installed.
  
              Run command with arguments. Wait for command to complete.
              If OSError raised, then raise :class:`EasyProcessCheckInstalledError`
              with information about program installation
  
              :param return_code: int, expected return code
              :rtype: self
  
              """
          try:
              self.call()
          except Exception:
  &gt;           raise EasyProcessCheckInstalledError(self)
  E           EasyProcessCheckInstalledError: cmd=['Xvfb', '-help']
  E           OSError=[Errno 2] No such file or directory
  E           Program install error!
  
  venv_pytest/lib/python2.7/site-packages/easyprocess/__init__.py:180: EasyProcessCheckInstalledError
  </code></pre>
  
  <p>Because it looks like an issue with <code>xvfb</code> I tried to install it:</p>
  
  <pre><code>&gt;pip install xvfb
  Collecting xvfb
    Could not find a version that satisfies the requirement xvfb (from versions: )
  No matching distribution found for xvfb
  </code></pre>
  
  <p>I also tried the following: </p>
  
  <pre><code>&gt;brew install xvfb
  Error: No available formula with the name "xvfb" 
  </code></pre>
  
  <p>What else can I try?</p>
  
  <p>Addendum: I am not loking for something else. I am looking to make the above work on a Mac to develop the tests. The tests will run in a sane Linux environment (of course not Mac!!) which is perfectly settled to work with <code>xvfb</code>...</p>