docs: def punchFile(rh):
      """
      Punch a file to a virtual reader of the specified virtual machine.
  
      Input:
         Request Handle with the following properties:
            function    - 'CHANGEVM'
            subfunction - 'PUNCHFILE'
            userid      - userid of the virtual machine
            parms['class']    - Spool class (optional)
            parms['file']     - Filespec of the file to punch.
  
      Output:
         Request Handle updated with the results.
         Return code - 0: ok, non-zero: error
      """
  
      rh.printSysLog("Enter changeVM.punchFile")
  
      # Default spool class in "A" , if specified change to specified class
      spoolClass = "A"
      if 'class' in rh.parms:
          spoolClass = str(rh.parms['class'])
  
      punch2reader(rh, rh.userid, rh.parms['file'], spoolClass)
  
      rh.printSysLog("Exit changeVM.punchFile, rc: " +
          str(rh.results['overallRC']))
      return rh.results['overallRC']