title: How do I get the build number from where I executed a rebuild?
body: <p>When I click "rebuild" from the page of a build jenkins rebuilds and runs a new job- a new job with a new jenkins build number.</p>
  
  <p>How do I get the build number of the job where I executed the rebuild? </p>
  
  <p>Im not talking about the previous build number.</p>
  
  <p>Say Im on build 10. I go to build 5 and click rebuild. How do I <em>that</em> build number (5) from inside the pipeline like I can with <code>env.BUILD_NUMBER</code>?</p>