Re: <filename> changed on disk; really edit the buffer?

Re: <filename> changed on disk; really edit the buffer?

[Richard Stallman]

    Also occurred to me that a possible use for auto-saving into the
    current file is when you don't have enough permissions in the
    current directory to create a new file.  

I think it would be better to put the auto save file in a different
directory.  In fact, perhaps we should change make-auto-save-file-name
to do this automatically.

Would someone like to try this?

Re: <filename> changed on disk; really edit the buffer?

[jonathangoldblatt]

What did you think of the auto-save-hooks idea?  In GNU Emacs
21.4.1 there is just 

auto-save-hook's value is nil

Documentation:
Normal hook run just before auto-saving.

Another possible advantage of auto-saving into the file is that
it simplifies using session-recover if something does go wrong.
I have one file that always shows up with an auto-save file and
what I always wind up doing is a compare with the original to
check that I really want to do the replace, which I always do.
Just struck me that I maybe I should set this file to save into
itself.  Unfortunately, it's a largish .gz, that takes a while to
save, but I might decide to stop being a bit miser, and just
use a normal file.  

I'd like to do some work on this stuff, and some of the other TO
DO's but unfortunately my personal life doesn't leave me with
enough time.  

Re: <filename> changed on disk; really edit the buffer?

[martin rudalics]

 >     Also occurred to me that a possible use for auto-saving into the
 >     current file is when you don't have enough permissions in the
 >     current directory to create a new file.
 >
 > I think it would be better to put the auto save file in a different
 > directory.  In fact, perhaps we should change make-auto-save-file-name
 > to do this automatically.

`make-auto-save-file-name' already tries to substitute the
default-directory in


		    (expand-file-name
		     (format "#%s#" buffer-name)
		     ;; Try a few alternative directories, to get one we can
		     ;; write it.
		     (cond
		      ((file-writable-p default-directory) default-directory)
		      ((file-writable-p "/var/tmp/") "/var/tmp/")
		      ("~/")))))

What else should it do?

Re: <filename> changed on disk; really edit the buffer?

[Richard Stallman]

    `make-auto-save-file-name' already tries to substitute the
    default-directory in

			(expand-file-name
			 (format "#%s#" buffer-name)
			 ;; Try a few alternative directories, to get one we can
			 ;; write it.
			 (cond
			  ((file-writable-p default-directory) default-directory)

That is in the branch for non-file buffers.

Re: <filename> changed on disk; really edit the buffer?

[Richard Stallman]

The idea makes sense.  The variables should be named
auto-save-functions, according to conventions since 15 years ago.

But it isn't quite straightforward, because the code in fileio.c uses
a static variable auto_saving which alters the behavior of
write-region.

We do theoretically have a problem with this now, since the call to
Fsleep_for could run a process filter or sentinel.  So it would be
good to change that mechanism.