code: public static Execed utilityAs(String as, Iterable<String> command) throws IOException
  	{
  		Exec e = new Exec(command);
  		if (as != null)
  			e.runAs(as);
  		e.setRedirectError(true);
  
  		return e.start();
  	}
docs: Runs a command in "utility" mode: redirecting stderr to stdout and optionally executing as a different user (eg root)
  
  @param as
  @param command
  
  @return
  
  @throws IOException