anchor.diff:      (ignore-errors(funcall (read-from-string "asdf::quit") ret))
       #+sbcl(ignore-errors(funcall (read-from-string "cl-user::exit") :code ret))
       #+sbcl(ignore-errors(funcall (read-from-string "cl-user::quit") :unix-status ret))
  -    #+clisp(ext:exit ret)))
  +    #+clisp(ext:exit ret)
  +    #+ccl(ccl:quit ret)))
   
   (defun run-program (args &key output)
     (if (ignore-errors #1=(read-from-string "uiop/run-program:run-program"))
  
positive.code: (defun exec (args)
    #+(and unix sbcl)
    (execvp (first args) args)
    (run-program args)
    (quit -1))
  
  
negative.code: (defun getenv (x)
    #+sbcl(sb-posix:getenv x)
    #+clisp(ext:getenv x)
    #+ccl(ccl:getenv x)
    #-(or sbcl clisp ccl) (funcall (read-from-string "asdf::getenv") x))
  
  (defun ros-opts ()
    (or *ros-opts*
  