title: Groovy script not able to execute external process
body: <p>I'm trying to execute a python external process from my Groovy script but it doesn't produce any output. </p>
  
  <p>So as a small sanity test I tried simply outputting the python version: </p>
  
  <pre><code>    def command = """ /usr/local/bin/python -V """
      def proc = command.execute()
      proc.waitFor()
      println "This is output: " + proc?.in?.text
  </code></pre>
  
  <p>The above doesn't produce any output, however, from my command line I AM able to run <code>/usr/local/bin/python -V</code></p>
  
  <p>What is weird is that if I modify the script to run <code>identify</code> then it does produce an output. </p>
  
  <pre><code>    def command = """ /usr/local/bin/identify --version """
      def proc = command.execute()
      proc.waitFor()
      println "This is output: " + proc?.in?.text
  </code></pre>
  
  <p>What can be causing this behavior? </p>