This is a mirror of http://www.vim.org/scripts/script.php?script_id=3107

Redirect backups made by the writebackup plugin (vimscript #1828) that would
normally go into the original file's directory into an adjacent directory with a
"{dir}.backup" name, if it exists. This allows to use the plugin in places where
backup files would cause problems.

DESCRIPTION
Many customization directories (e.g. /etc/profile.d/) consider all contained
files, regardless of file extension or execute permissions. Creating a
{file}.YYYYMMDD[a-z] backup in there causes trouble and strange effects,
because the backups are used in addition to the main configuration file - not
what was intended! However, putting the backups in the same directory
generally is a good idea - just not for these special directories.

This plugin offers a solution by integrating into the writebackup.vim plugin
so that it checks for a directory with a '.backup' extension (e.g.
/etc/profile.d.backup/), and places the backups in there, in case it exists.
In all other cases, the backup is made in the default directory, as before.

USAGE
Adjacent backup directories are never created by this plugin; you have to
create such a directory yourself to indicate that backups should be placed in
there.

:WriteBackupMakeAdjacentDir [../..|/path/to/dir] [{prot}]
                Create a backup directory adjacent to the current file's
                directory, or in a parent of that ("..", "../..", etc.), or of
                any passed directory.
                If {prot} is given it is used to set the protection bits;
                default is 0755.

After the adjacent backup directory has been created, just use :WriteBackup
as before.