title: node.js call external exe and wait for output
body: <p>I just want to call an external exe from a nodejs-App. This external exe makes some calculations and returns an output the nodejs-App needs. But I have no idea how to make the connection between nodejs and an external exe. So my questions:</p>
  
  <ol>
  <li>How do I call an external exe-file with specific arguments from within nodejs properly?</li>
  <li>And how do I have to transmit the output of the exe to nodejs efficiently?</li>
  </ol>
  
  <p>Nodejs shall wait for the output of the external exe. But how does nodejs know when the exe has finished its processing? And then how do I have to deliver the result of the exe? I don't want to create a temporary text-file where I write the output to and nodejs simply reads this text-file. Is there any way I can directly return the output of the exe to nodejs? I don't know how an external exe can directly deliver its output to nodejs. BTW: The exe is my own program. So I have full access to that app and can make any necessary changes. Any help is welcome...</p>