Making a backup file on every buffer save?

Making a backup file on every buffer save?

[Roy Smith]

The docs say:

"Emacs makes a backup for a file only the first time the file is
saved from a buffer.  No matter how many times you subsequently save
the file, its backup remains unchanged.  However, if you kill the
buffer and then visit the file again, a new backup file will be made."

Is there any way to override this and get a backup file on every
buffer save?  I'm using GNU Emacs 23.1.1.

I recently managed to blow away a file on disk that I had been editing
and no longer had a copy in an emacs buffer.  I had the backup from
the last time I had visited the file, but had done a lot of work since
then and had saved many intermediate versions.  If those intermediate
saves had generated backups, I would have avoided losing a bunch of
work.  The disk and CPU costs for this are trivial on modern hardware.

Re: Making a backup file on every buffer save?

[Alain Ketterlin]

Roy Smith <roy@panix.com> writes:

> The docs say:
>
> "Emacs makes a backup for a file only the first time the file is
> saved from a buffer.  No matter how many times you subsequently save
> the file, its backup remains unchanged.  However, if you kill the
> buffer and then visit the file again, a new backup file will be made."
>
> Is there any way to override this and get a backup file on every
> buffer save?  I'm using GNU Emacs 23.1.1.

A few paragraphs later, the doc mentions that C-u C-u C-x C-s should do
what you want (but I guess auto-save is supposed to solve the kind of
problem you had). Or you can call make-backup explicitly.

-- Alain.

Re: Making a backup file on every buffer save?

[Roy Smith]

On May 2, 10:32 am, Alain Ketterlin <al...@dpt-info.u-strasbg.fr>
wrote:
> Roy Smith <r...@panix.com> writes:
> > The docs say:
>
> > "Emacs makes a backup for a file only the first time the file is
> > saved from a buffer.  No matter how many times you subsequently save
> > the file, its backup remains unchanged.  However, if you kill the
> > buffer and then visit the file again, a new backup file will be made."
>
> > Is there any way to override this and get a backup file on every
> > buffer save?  I'm using GNU Emacs 23.1.1.
>
> A few paragraphs later, the doc mentions that C-u C-u C-x C-s should do
> what you want (but I guess auto-save is supposed to solve the kind of
> problem you had). Or you can call make-backup explicitly.
>
> -- Alain.

Oh, duh.  I just didn't read far enough.  Thanks for pointing that
out!