When I edit and save files, Vim creates a file with the same name as

the original file and a “un~” extension at the end. How do I stop Vim from creating this file (or) How do I disable the Vim undofile feature? Vim 7.3 contains as new feature persistent undo, that is, undo information won’t be lost when quitting Vim and be stored in a file that ends with “.un~” You have set the ‘undofile’ option, so Vim creates an undo file when saving the original file. You can stop Vim from creating the backup file, by clearing the option:

    :set noundofile

Note that, by default this option is turned off. You have explicitly enabled the ‘undofile’ option in one of the initialization files. If you want your undofiles to be stored only in a particular directory, you can point the ‘undodir’ option to a directory that will contain all your aggregated undofiles.