Re: rename buffer but overwrite already existing one

[Stephen Berman]

On Mon, 23 Mar 2020 20:43:56 +0100 Uwe Brauer <address@hidden> wrote:

>>>> "AS" == Andreas Schwab <address@hidden> writes:
>
>    > On Mär 23 2020, Uwe Brauer wrote:
>    >>>>> "EZ" == Eli Zaretskii <address@hidden> writes:
>    >> 
>    >> >> From: Uwe Brauer <address@hidden>
>    >> >> Date: Mon, 23 Mar 2020 19:05:23 +0100
>    >> >> 
>    >> >> Couldn't rename-buffer, optionally, overwrite the content of a 
> buffer.
>    >> 
>    >> > Yes, but it's called copy-to-buffer, not rename-buffer.
>    >> 
>    >> Thanks for pointing this out to me, but I have to mark the whole buffer
>    >> first, which is a but inconvenient, I say.
>    >> 
>    >> Couldn't there an argument added so that with the argument the whole
>    >> buffer is copied?
>
>    > It's easy to define your own function that calls copy-to-buffer with
>    > (point-min), (point-max).
>
> That is what I thought
>
> (defun my-copy-to-buffer (buffer)
>   "Copy to specified BUFFER the whole buffer."
>   (interactive "BCopy to buffer: \n")
>   (let ((oldbuf (current-buffer)))
>     (with-current-buffer (get-buffer-create buffer)
>       (barf-if-buffer-read-only)
>       (erase-buffer)
>       (save-excursion
>       (insert-buffer-substring oldbuf (point-min) (point-max))))))
>
>
> Does not work zero bytes where copied, there is something I miss, obviously.

You're calling insert-buffer-substring with point-min and point-max of
the buffer you've just created, so they're both 1.  Try this:

(defun my-copy-to-buffer (buffer)
  "Copy the contents of the current buffer to  BUFFER."
  (interactive "BCopy to buffer: ")
  (let ((start (point-min))
        (end (point-max)))
    (copy-to-buffer buffer start end)))

Steve Berman