Auto-backup your configuration files with Vim — First published in fullweb.io issue #71

auto-backup-your-configuration-files-with-vim.md

Auto-backup your configuration files with Vim

Not using versioning on your configuration files and editing them with Vim?

Use Vim’s backup option to automatically keep a copy of past versions. To put in your ~/.vimrc:

"Turn on backup option
set backup

"Where to store backups
set backupdir=~/.vim/backup//

"Make backup before overwriting the current buffer
set writebackup

"Overwrite the original backup file
set backupcopy=yes

"Meaningful backup name, ex: filename@2015-04-05.14:59
au BufWritePre * let &bex = '@' . strftime("%F.%H:%M")

From now on, each time you’ll save a file (hit :w), Vim will save a copy in ~/.vim/backup/ with this syntax your-file.py@2016-10-25.14:58.

This honestly saves my life about once a year 😁.

@webcaptcha if you put these settings into your own ~/.vimrc, then, by default, root will not use those settings. For root to use similar settings by default, you would need to muck with a .vimrc file in /root or change system-wide defaults. These are not good options because they mean you are changing something that root interacts with, and breaking root is a really bad thing to risk.

However, sudo has a fix built right into it, just like they were thinking of you. :) Use the --preserve-env parameter (sudo --preserve-env vim) and your environment variables will be retained. For me, this is enough to retain my vim customizations, so I hope it works for you also.

I am not a vim hacker, just a consumer of plugins. I would like to add path information to the backup files, so that I could have names like %home%sql-sith%docs%gists%myfile.txt@2022.03.24.16.04.04.10. This would help me easily distinguish common file names like README.md that are in several different folders.

Is this possible? Alternatively, where is documentation that could help me understand things like au BufWritePre * let &bex = '@' . strftime("%F.%H:%M") so I could just answer my own questions? Thanks.

Updated answer:
@sql-sith I actually overcomplicated it 😂.

From :help backupdir

• For Unix and Win32, if a directory ends in two path separators "//",
  the backup file name will be built from the complete path to the
  file with all path separators changed to percent '%' signs. This
  will ensure file name uniqueness in the backup directory.
  On Win32, it is also possible to end with "\". However, When a
  separating comma is following, you must use "//", since "\" will
  include the comma in the file name. Therefore it is recommended to
  use '//', instead of '\'.

so you can just add two slashes to the end of backupdir to get the desired result:

set backupdir=~/.backup//
set backup
set backupcopy=yes
set backupext=.bak
set writebackup

and it will look like

%Users%mike%.vimrc.bak

Old answer:

Hi @sql-sith, the documentation can be found here: https://vimhelp.org/options.txt.html#%27bex%27. (Same as :help bex)

https://vimhelp.org/builtin.txt.html#expand%28%29 (:help expand) has the information regarding the meaning of %.

Since this is the extension that is used, you can append to the filename. Something like this should help you:

:echo substitute(expand('%:p'), '/', '%', 'g').'@'.strftime("%F.%H:%M")

%Users%mike%.bashrc@2023-02-02.20:17 

The file would end up looking like this:

.bashrc%Users%mike%.bashrc@2023-02-02.20:17

Its really awesome solution but eventually one will have to manually delete the older backup. is there a way to delete the files older than 7-14 days while initialising vim?

maybe something like this could help:

silent execute '!find $HOME/.vimtmp/backup -type f -mtime +7 -delete'