title: how to run node shelljs in sync mode and get stdout and stderr
body: <p>Within a nodejs script I have the following code which makes the call synchronously and returns the stdout from the shell script I am calling:</p>
  
  <pre><code>var sh = require('shelljs');
  
  ... some code
  var output = sh.exec('./someshellscript.sh', {silent:true}).stdout;
  console.log(output);
  ... some more code (that shouldnt run until the script is complete)
  </code></pre>
  
  <p>I can also run the following script which will instead return the stderr:</p>
  
  <pre><code>var sh = require('shelljs');
  
  ... some code
  var output = sh.exec('./someshellscript.sh', {silent:true}).stderr;
  console.log(output);
  ... some more code (that shouldnt run until the script is complete)
  </code></pre>
  
  <p>However I want to receive both stdout and stderr in a sync call. Its probably something pretty obvious I am missing herebut I cant work it out.</p>
  
  <p>I think you used to be able run the following command in previous versions but this just returns undefined now:</p>
  
  <pre><code>var sh = require('shelljs');
  
  ... some code
  var output = sh.exec('./someshellscript.sh', {silent:true}).output;
  console.log(output);
  ... some more code (that shouldnt run until the script is complete)
  </code></pre>
  
  <p>Relevant software versions are:</p>
  
  <ul>
  <li>Ubuntu: 14.04.3 LTS</li>
  <li>node: 4.4.4</li>
  <li>npm: 2.15.1</li>
  <li>shelljs: 0.7.0</li>
  </ul>
  
  <p>Any help appreciated thanks.</p>