anchor.diff:             (let* ((whole (gensym "WHOLE"))
                     (args (apply 'concatenate 'list (mapcar #'macro-argify arg-descriptions))))
                `(defmacro ,lisp-name (&whole ,whole ,@args)
  +                ,(format nil "This macro is a wrapper around the ~A C function.
  +
  +It will signal a `syscall-error' if the following predicate returns nil.
  +~S" c-name error-checker)
                   (declare (ignore ,@(remove '&rest args)))
                   `(let ((,',result (,',lisp-impl-name ,@(cdr ,whole))))
                      (unless (funcall ,',error-checker ,',result)
  
positive.code:              (format s "Encountered an error (~A) in ~A.  ~A"
                       (syscall-errno c)
                       (syscall-error-function c)
                       (strerror (syscall-errno c))))))
  
  (defun pass (value)
    "Returns t."
  
negative.code: 
  (optimization-settings)
  
  (defgeneric syscall-errno (syscall-error)
    (:documentation
     "Return the errno that was set when the given condition was
  signaled."))
  
  (define-condition syscall-error (error)
    ((errno
      :initform errno
  