Hi!

make-backup-file-name-function is a customizable variable in files.el for
deciding the backup file name for a file. find-backup-file-name uses
make-backup-file-name-1 for finding out the base names of the backup files:

from find-backup-file-name:

    (let* ((basic-name (make-backup-file-name-1 fn))
           (base-versions (concat (file-name-nondirectory basic-name)
                      ".~"))

This assumes that make-backup-file-name is used for generating the backup
file
names, while make-backup-file-name-function could be customized. The result
of
this is, any customization to make-backup-file-name-function doesn't work as
expected when the backup file name is in a different place than what is
provided
by the stock function (like say, a different directory).

Changing the code above to:

    (let* ((basic-name (file-name-sans-versions (make-backup-file-name fn)))
           (base-versions (concat (file-name-nondirectory basic-name)
                      ".~"))

would solve this problem, as this would go through the proper hook.

Ramkumar.

PS: Please CC me in the replies: I am not a part of the list.

In GNU Emacs 23.0.60.1 (i486-pc-linux-gnu, GTK+ Version 2.12.9)
 of 2008-03-20 on elegiac, modified by Debian
 (emacs-snapshot package, version 1:20080320-1)
Windowing system distributor `The X.Org Foundation', version 11.0.10300000
configured using `configure  '--build' 'i486-linux-gnu' '--host'
'i486-linux-gnu' '--prefix=/usr' '--sharedstatedir=/var/lib'
'--libexecdir=/usr/lib' '--localstatedir=/var' '--infodir=/usr/share/info'
'--mandir=/usr/share/man' '--with-pop=yes'
'--enable-locallisppath=/etc/emacs-snapshot:/etc/emacs:/usr/local/share/emacs/23.0.60/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/23.0.60/site-lisp:/usr/share/emacs/site-lisp:/usr/share/emacs/23.0.60/leim'
'--with-x=yes' '--with-x-toolkit=gtk' 'build_alias=i486-linux-gnu'
'host_alias=i486-linux-gnu' 'CFLAGS=-DDEBIAN -DSITELOAD_PURESIZE_EXTRA=5000
-g -O2''

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