12. Specify Directories to be Used for Backup Files

Allows backup files to be optionally stored in some directories, based on the value of the alist, bkup-backup-directory-info. This variable is a list of lists of the form (FILE-REGEXP BACKUP-DIR OPTIONS ...). If the filename to be backed up matches FILE-REGEXP, or FILE-REGEXP is t, then BACKUP-DIR is used as the path for its backups. Directories may begin with "/" to specify an absolute pathname.

If BACKUP-DIR does not exist and OPTIONS contains the symbol ok-create, then it is created if possible. Otherwise the usual behavior (backup in the same directory as the file) results.

If OPTIONS contains the symbol full-path, then the full path of the file being backed up is prepended to the backup file name, with each "/" replaced by a "!". This is intended for cases where an absolute backup path is used. If OPTIONS contains prepend-name in addition to full-path, then the file name is prepended rather than appended to the path component when forming the backup name.

If OPTIONS contains the symbol search-upward and the backup directory BACKUP-DIR is a relative path, then a directory with that name is searched for starting at the current directory and proceeding upward (.., ../.., etc) until one is found of that name or the root is reached, and if one is found it is used as the backup directory.

Finally, if no FILE-REGEXP matches the file name being backed up, then the usual behavior results.

These lines from my initialization file load this library and set the values I like:

  (require 'backup-dir)
  (setq bkup-backup-directory-info
        '(("/home/greg/.*" "/~/.backups/" ok-create full-path prepend-name)
          ("^/[^/:]+:"     ".backups/") ; handle EFS files specially: don't 
          ("^/[^/:]+:"     "./")        ; search-upward... its very slow
          (t               ".backups/"
                           full-path prepend-name search-upward)))

The package also provides a new function, find-file-latest-backup to find the latest backup file for the current buffer’s file.

This package is based on ‘files.el’ from XEmacs 20.3 and overrides functions defined there.

This document was generated by Aidan Kehoe on December 27, 2016 using texi2html 1.82.