29.1.9 Ignore Version Control Files

C-x v G

Ignore a file under current version control system. (vc-ignore).

Many source trees contain some files that do not need to be versioned, such as editor backups, object or bytecode files, and built programs. You can simply not add them, but then they’ll always crop up as unknown files. You can also tell the version control system to ignore these files by adding them to the ignore file at the top of the tree. C-x v G (vc-ignore) can help you do this. When called with a prefix argument, you can remove a file from the ignored file list.