问如何使用Emacs将当前日期和时间插入到文件中？

EN

C-u M-! date

;; ====================
;; insert date and time

(defvar current-date-time-format "%a %b %d %H:%M:%S %Z %Y"
  "Format of date to insert with `insert-current-date-time' func
See help of `format-time-string' for possible replacements")

(defvar current-time-format "%a %H:%M:%S"
  "Format of date to insert with `insert-current-time' func.
Note the weekly scope of the command's precision.")

(defun insert-current-date-time ()
  "insert the current date and time into current buffer.
Uses `current-date-time-format' for the formatting the date/time."
       (interactive)
       (insert "==========\n")
;       (insert (let () (comment-start)))
       (insert (format-time-string current-date-time-format (current-time)))
       (insert "\n")
       )

(defun insert-current-time ()
  "insert the current time (1-week scope) into the current buffer."
       (interactive)
       (insert (format-time-string current-time-format (current-time)))
       (insert "\n")
       )

(global-set-key "\C-c\C-d" 'insert-current-date-time)
(global-set-key "\C-c\C-t" 'insert-current-time)

(defun now ()
  "Insert string for the current time formatted like '2:34 PM'."
  (interactive)                 ; permit invocation in minibuffer
  (insert (format-time-string "%D %-I:%M %p")))

(defun today ()
  "Insert string for today's date nicely formatted in American style,
e.g. Sunday, September 17, 2000."
  (interactive)                 ; permit invocation in minibuffer
  (insert (format-time-string "%A, %B %e, %Y")))