Need a Elisp function to push back an input

I wrote a new version of "zap-to-char".It just highlights the region instead of kill it.I think this would be more flexible,because开发者_C百科 we can choose to kill,or copy,or just go to this char.

Here is the snippet:

(defun new-zap-to-char (arg char)
  (interactive "p\ncZap to char: ")
  (push-mark)
  (setq mark-active t)
  (defun iter-zap ()
    (if (< arg 0)
      (search-forward (char-to-string char) nil nil -1)
      (search-forward (char-to-string char) nil nil 1))
    (if (char-equal char (setq c (read-char)))
        (iter-zap)
        (>>>>here is the "push-back-to-input" function"<<<<))
 (iter-zap))

As you see, I need a function to push the result of 'read-char' back to input,when you type input except for the "char". But I don't know if Emacs offered one. So I need your help.

I hope I've made this clear.

---

You can try unread-command-events.

For example:

(push ?a unread-command-events)