title: checking status of process with subprocess.Popen in Python
body: <p>If I invoke a process with <code>subprocess.Popen</code> in Python as follows:</p>
  
  <p><code>myproc = subprocess.Popen(...).communicate()</code></p>
  
  <p>what is the correct way to see its status? Not its output to stdout or stderr, but its exit status once it's finished (e.g. 0 for success or another for failure)?</p>